domain: shs sde sdu

text:
Kelut Krakatau

Tambora

Turgo Village

Kayen Village

B Sukatja

Balai Sabo

2007 lava dome of Kelut Volcano 2007 lava dome of Kelut volcano Rinjani volcano and its caldera lake Rinjani volcano and its caldera lake Toba caldera and lake Toba caldera and lake RINJANI TOBA

Keywords: MVO, ORARI, National television, Radio Jalin Merapi BPPTK E700XD antenna E700XD antenna

Rapid renewed short-lived dome growth associated

). The objective of this 48-month project was to develop integrated tools and cost effective methodologies to mitigate risks from various volcanic hazards (vulnerability and resilience assessment, prevention and crisis management) on four active volcanoes: Merapi (Indonesia), Kanlaon (the Philippines), Fogo (Cape Verde), and Mount Cameroon (Cameroon).

(ii) The SEDIMER Project (Sediment-related Disasters following the 2010 centennial eruption of Merapi Volcano, Java, Indonesia), is funded by the AXA Research Fund (2011[START_REF] Solikhin | Mapping the 2010 Merapi pyroclastic deposits using dual-polarization Synthetic Aperture Radar (SAR) data[END_REF], and is led by the Laboratoire de Géographie Physique (CNRS). This ongoing project aims at building a database on lahar occurrence and related disasters, to identify the sediment sources for lahar generation, study the lahar dynamics and geomorphic impacts with implications for risk prevention. Both projects are collaborative studies that gather international and Indonesian experienced experts and young scientists in geography, geomorphology, hydrogeology, sedimentology, volcanology, geophysics, sismology, petrology, modeling, GIS, statistics, etc.

In the past, comprehensive reference works summarising the current state of knowledge of some active volcanoes were gathered into an atlas, e.g. the Volcanic Hazard Atlas of the Lesser Antilles (Lindsay et al., 2005). Individual island-specific entries include sections that summarise all previous work, the geological history of the islands, and the monitoring network of the volcanoes. Each potentially active volcano on the island is then discussed in turn, with emphasis on past eruptive activity, geothermal activity and seismicity. Unlike this approach, the atlas of Merapi is the first atlas focusing entirely on a single active volcano. Another significant difference is that it does not focus exclusively on the geology, or the volcanic hazards and the monitoring of the volcano. Yet it covers a much wider spectrum in order to assess the actual volcanic risk. Therefore, it encompasses original sections on resources, vulnerabilities, and capacities in addition to the more conventional sections dedicated to Earth Science. The maps of this atlas are mainly based on field data compiled during a 2-years long census campaign (2009 -2010) in the framework of the MIA VITA project. More than 550 questionnaires have been filled out at the scale of the village (dusun). In Indonesia, the lowest official administrative unit is the municipality (desa), therefore the village's borders were not available at the beginning of this study. Finally they were drawn using participatory mapping based on local traditional knowledge.

Scientific context

The first atlas on an active volcano A digital atlas in free access

In addition to the hard copy version of the atlas dedicated to the local stakeholders, a digital version is available online in pdf format.

New eruptions at Merapi will probably require frequent updating of this atlas. For this reason, it must be stressed that the plates of the Atlas should not be viewed as fixed. The online version will be updated as new information comes to light, or in case of a new eruption. In addition, existing plates will be enhanced, and new plates will be progressively added, e.g. plates on the main historical eruptions, plate on volcanic tourism at Merapi, etc. In the long term, the atlas will become the comprehensive reference work on the physical and human geography of Merapi.

S E D I M E R

This atlas of Merapi volcano is a result of a collaborative research from two successive scientific projects:

summary Merapi volcano is one of the most active volcanoes worldwide. Approximately 1.3 million people live within a radius of 20 km from the summit. In the framework of both, the FP7 MIA VITA Project, and the SEDIMER Project funded by AXA Research Fund, we have built a database at the village scale, which includes the elements at risk and the local resources. This unique geospatial database was used to build a series of maps at the scale of the volcano, providing the core of the Merapi atlas. Designed by the French Laboratory of Physical Geography in Meudon (France) and the Center of Volcanology and Geological Hazards Mitigation in Bandung (Indonesia), this atlas provides a state of the art synthesis of knowledge on Merapi, from the reconstruction of past eruptions and assessment of volcanic hazards to the quantification of vulnerability and capacities. It is pertinent to a broad audience ranging from volcanologists to the Indonesian population interested to learn about their sacred volcano. The primary goal of this atlas is to provide an essential blueprint for planners and public officials involved in long-term development as well as risk and crisis management. The first edition of the atlas contains 58 color plates gathered in 8 chapters: the first chapter introduces the broad tectonic and geologic context as well as the environmental and human context of Merapi volcano. The second chapter pertains to the geology, the past activity, and the volcanic hazards at Merapi. The third chapter is dedicated to the resources offered by the volcano, including agriculture, livestock, and sand mining activities. The fourth chapter focuses on vulnerability and capacities. The fifth chapter details the 2010 VEI 4 eruption of Merapi and its environmental consequences.

The sixth chapter summarises the socio-economical impact of the eruption, including mapping of casualties, evacuation, building damage, and an assessment of air traffic disturbance. The seventh chapter focuses on rain-triggered lahar activity following the 2010 eruption, and the associated impact at the local scale. In the concluding chapter, we show how the 2010 eruption of Merapi improved volcanic risk management, through an updated volcanic hazard map, the establishment of a new high-tech monitoring system, as well as the increase of risk awereness. Extensive use of colour in maps at various scales, graphics, and photos, provides a visually appealing synthesis of the hazards and risks at Merapi volcano, one of the most dangerous in the world.

Ringkasan

Gunungapi Merapi merupakan salah satu gunungapi yang paling aktif di dunia. Lebih kurang 1.300.000 penduduk tinggal di radius 20 km dari puncak Gunungapi Merapi. Melalui proyek FP7 MIA VITA dan SEDIMER yang di danai oleh AXA, kami telah membuat database dalam skala desa yang mencakup unsur-unsur risiko dan sumberdaya lokal. Database geospasial digunakan untuk membuat seri peta pada skala gunungapi yang tersaji dalam Atlas Merapi. Atlas Merapi disusun oleh "French Laboratory" Geografi Fisik di Meudon (Perancis) dan Pusat Vulkanologi dan Mitigasi Bahaya Geologi di Bandung (Indonesia), atlas ini menyajikan perpaduan antara seni dan pengetahuan tentang Merapi dari rekonstruksi letusan masa lalu dan penilaian bahaya vulkanik dengan perhitungan kerentanan dan kapasitas (daya tampung). Atlas Merapi berkaitan dengan khalayak luas, mulai dari ahli gunungapi sampai penduduk Indonesia yang tertarik untuk belajar tentang gunungapi. Tujuan utama pembuatan Atlas ini adalah memberikan gambaran penting bagi perencana dan pejabat publik yang terlibat dalam pembangunan jangka panjang seperti risiko dan krisis manajemen. Atlas ini terdiri dari puluhan halaman yang tersusun dalam 8 bab, yakni pendahuluan tentang rangkuman konteks geologi meliputi konteks lingkungan dan manusia di sekitar Gunungapi Merapi. Bab kedua berkaitan dengan geologi, aktivitas masa lalu, dan bahaya vulkanik di Gunungapi Merapi. Bab ketiga membahas tentang sumberdaya yang disediakan oleh gunungapi Merapi, termasuk pertanian, peternakan, dan kegiatan penambangan pasir. Bab keempat fokus pada kerentanan dan kapasitas (daya tampung). Bab kelima menyajikan tentang rekonstruksi VEI 4 pada letusan Merapi tahun 2010 dan konsekuensi lingkungannya. Bab keenam merupakan rangkuman dampak sosial-ekonomi dari letusan Gunungapi Merapi, termasuk pemetaan korban, evakuasi, kerusakan bangunan, dan penilaian gangguan lalu lintas udara. Bab ketujuh fokus membahas aktivitas lahar yang dipicu oleh hujan setelah letusan Gunungapi Merapi pada tahun 2010, dan dampak yang terjadi dalam skala lokal. Dalam penutup bab, kami menunjukkan bagaimana manajemen risiko letusan Gunungapi Merapi pada tahun 2010 semakin baik, melalui peta bahaya vulkanik yang telah diperbarui, pembuatan sistem pemantauan berteknologi tinggi, serta peningkatan kesadaran risiko. Penyajian peta menggunakan warna di berbagai skala, grafis, dan foto ditujukan agar pembaca mudah memahami bahaya dan risiko di Gunungapi Merapi, salah satu gunungapi yang paling berbahaya di dunia. Source: Modified after mapsofworld.com and www.treehouse-maps.com.

The Indonesian archipelago is the result of complex tectonic plate collision involving four different plates. Subduction of the continental Indo-Australian plate beneath the Eurasian plate formed the main Sunda-Banda volcanic arc stretching from Sumatra to the West, through Java, Bali, Nusa Tengara Islands till Banda to the East. To the East, subduction of the oceanic Pacific and Philippine Sea plates beneath the Eurasian plate has generated the Maluku and Sulawesi volcanic and tectonic provinces. The process of rapid subduction leads to the genesis of mountain chains, a high rate of volcanic activity, and tremendous stresses in the Earth's crust that cause its rupture along active faults. This makes this region one of the most seismically active of the World. From historical and seismic records, we know that very strong earthquakes with magnitude > 8 have occurred in the past almost everywhere in Indonesia, except in Borneo Island. Major earthquakes occur along the Sumatran Fault about once or twice every decade. Earthquakes of magnitude > 8 have been directly responsible for thousands of fatalities on this island (e.g. in 1833 or 1861). On 26 December 2004 (i.e. Boxing Day), a 9.1-magnitude earthquake triggered a tsunami in the Indian Ocean that killed 230,000 people, nearly three-quarters of whom were in Aceh [START_REF] Lavigne | Reconstruction of Tsunami Inland Propagation on December 26, 2004 in Banda Aceh, Indonesia, through Field Investigations[END_REF]. In October 2010, ten villages on the Mentawai islands were swept away by a 3-meters tsunami generated by a 7.7 magnitude quake. Deadly earthquakes triggering potential tsunami are also frequent in Java; in 2006, 5,700 people were killed by the 27 May earthquake and more than 800 by the 17 July tsunami. Deadly tsunamigenic earthquakes may also occur off the Lesser Sunda Islands (e.g. Flores in 1992 or Sumba in 1977) or off Papua (1996).

An island-arc setting includes a chain of offshore, island volcanoes above a subducting plate. The back-arc is located opposite the trench and subducting plate, behind the chain of volcanoes called an "island arc".

Source: [START_REF] Lavigne | Reconstruction of Tsunami Inland Propagation on December 26, 2004 in Banda Aceh, Indonesia, through Field Investigations[END_REF] Tsunami propagation across Banda Aceh on 26.12.2004

A.1

Tectonics of Indonesia © F. Lavigne, 2005 Indian Ocean A recent study demonstrated that a similar -an even larger-catastrophic eruption occurred in AD 1257 in Lombok island [START_REF] Lavigne | Source of the Great AD 1257 Mystery Eruption Unveiled, Samalas Volcano, Rinjani Volcanic Complex, Indonesia[END_REF]. Like at Tambora, the summit of Mount Samalas, a former volcano part of the Rinjani volcanic complex, collapsed to form a 6-km wide caldera. Based on ice core records, this eruption yielded the largest volcanic sulfur release to the stratosphere in the past 7000 years. The huge amount of ash (in excess of 30 km³) blasted into the upper atmosphere by the 1257 and 1815 eruptions of Samalas and Tambora contributed to an abnormal and highly destructive worldwide weather event the following year. Both 1258 and 1816 became a year without a summer in Europe and Northern America. Widespread crop failures caused hunger and even famine in some places. Further back in time, the Toba super-eruption that occurred about 73,000±4000 years Before Present (BP) might have expelled ~ 2800 km³ of volcanic material, and made a sizable contribution to the present 100×30 km caldera complex.

Location of merapi volcano

Merapi stratovolcano (2965 m) is located in Java, Indonesia, 30 km north of the city of Yogyakarta. This region is famous for its pre Islamic temples, especially Borobudur and Prambanan temples.

Merapi is the last edifice of a WNW-ESE trending chain of volcanoes in Central Java. It includes Mt. Sumbing (3371 m. a.s.l.) and Mt. Sindoro (3151 m a.s.l.), which are active volcanoes although their activity has been very limited over the past centuries (e.g. Sumbing has had only one historic eruption in 1730). On the other end of the chain, Dieng Volcanic Complex is expressed topographically as a highland plateau (~2000 m a.s.l.), with an extensive assemblage of spatially, temporally, and genetically related major and minor volcanic centers. Merapi belongs to a second group of four stratovolcanoes oriented N-S that includes Ungaran, Telomoyo and Merbabu volcanoes.

Administratively, it is located on the border four districts or kabupaten: Sleman in the Special Region of Yogyakarta, and Magelang, Boyolali and Klaten in the Central Java Province. Due to the wind direction during the rainy season and to topographic effects, the rainfall is more intense on Merapi's western flank. The 15-year average annual rainfall between 1976 and 1990 was 3253 mm at Plawangan (1275 m elevation, south slope) and 2,416 mm at Babadan). However, the actual yearly amount ranges at various stations from 2000 mm to 4500 mm.

Although typhoons do not strike Indonesia, the heaviest rains occur during high-intensity tropical storms. Exceptional rainfall can be as much as 466 mm/day recorded at Ngepos station on 25 November 1979. Between 1980 and 2000, rainfall exceeded 100 mm/h at least seven times on the slopes of Merapi [START_REF] Lavigne | Lahars at Merapi volcano: an overview[END_REF]. The role of rainfall is crucial, as it remobilizes volcanic material, triggering lahars (volcanic debris flows). At Merapi, the time of lahar generation coincides with strong rainfall intensity.

Two types of triggering rainfalls are commonly distinguished, local rainfall (also termed stationary, orographic, or updraft rainfall), confined to slopes above 1200 m in elevation, and regional (or migratory) rainfall, that is transported from the NW or the SW [START_REF] Lavigne | Lahars at Merapi volcano: an overview[END_REF].

thousands of migrants have settled within areas prone to floods and lahars along the Code river.

In 1995, about 13,000 people were already living at risk in the suburbs of Yogyakarta along the Code River with the population density exceeding 5600 inhabitants per km².

Villages located on Merapi's western flank are densely populated due to the importance of rice cultivation. A very high population density is required, as this type of farming is very labour intensive since all work is done by hand. As this activity can develop along steep slopes, high population density is noted up to Ngargomulyo's altitude, within the 10 km radius around the summit.

A Highly Populated Volcano

A.5 ocal people on t e Merapi slopes ocal people on t e Merapi slopes

The Geology of Merapi and Its Volcanic Hazards

New Merapi

Old Merapi

Proto-Merapi

Merapi -Volcano-stratigraphic units Recent and mostly historical pyroclastic-flow and lahar deposits AD -Present (historical accounts and 14 C dating)]

Young (post-Somma-Merapi) lava flows [START_REF] Newhall | 10,000 years of explosive eruptions at Merapi Volcano, Central Java: Archaeological and modern implications[END_REF]: the Proto-Merapi (>5000 BC), the Old Merapi (5000 BC-0 AD), and the New Merapi (since 0 AD). Plawangan and Turgo hills on the Southern flank of the volcano, as well as Bibi hill on the Eastern flank, are considered remnants of old lava flows (>100,000 years) from the Proto-Merapi. The Eastern flank of the present edifice is also covered by more recent lava flows (purple on the map), dated from 30,000 to 5,000 years [START_REF] Gertisser | The geological evolution of Merapi volcano, Central Java, Indonesia[END_REF]. The arcuate faults on this flank are thought to parallel the scars of at least two flank failures whose ages are still debated. The main collapse which may have occurred between 1600 and 1100 year BP [START_REF] Newhall | 10,000 years of explosive eruptions at Merapi Volcano, Central Java: Archaeological and modern implications[END_REF] left a somma rim high on Merapi's eastern slope that may parallel the Pasarbubar crater rim. At a radial distance of a few kilometers from the Merapi cone, the volcanic deposits that are now exposed (from pyroclastic flows and surges, ash fall and lahars) are essentially Holocene in age. Main hazards Main Pyroclastic deposits since 1930 Pyroclastic Density Currents (PDCs) are a combination of superheated gases and rocks (tephra, between 200 and 1000°C) rushing down the flanks of volcanoes at velocities reaching up to 194 m/s (700 km/h). They raze and burn everything to the ground on their way. There are two main types of PDCs: (1) concentrated pyroclastic flows controlled by topography, and (2) dilute turbulent high energy currents (pyroclastic surges).

Volcanic ash is composed of small fragments (<2 mm) of pulverized rock, minerals and volcanic glass. It is ejected into the air by volcanic eruptions and spreads widely. Ash can generate health problems for people and livestock, disrupt air traffic, transportation, and damage electric power supply systems, as well as communications, water and waste-water networks. Ash also impacts buildings (e.g. roof collapse).

Lahars are debris flows or hyperconcentrated flows composed of volcanic material transported by water. At Merapi, their occurrence is due to intense precipitation that re-mobilizes unstable materials left by previous eruptions. Their surface velocity is between 2 and 8 m/s (7 to 29 km/h), and their discharge reaches hundreds of cubic meters per second (peaks can reach 1800 m³/s or more at Merapi).

Eruptive History and Hazards

Over the last two centuries, Merapi's activity has regularly alternated between long periods of viscous lava dome extrusion and brief explosive episodes at 5-8 year intervals, which generated dome-collapse pyroclastic flows and destroyed part of the pre-existing domes.

Violent explosive episodes recurring every 26-54 years on average have generated pyroclastic flows, surges, tephra-falls, and subsequent lahars.

One of the most dangerous hazards at Merapi is the dome-collapsed pyroclastic flow, also called "Merapitype nuée ardente". Although its travel distance is usually less than 8 km, this type of pyroclastic density currents (PDCs) occurs without any natural (e.g. seismic) warning. On 22 November 1994, 64 people were killed by such events in the Turgo village.

The 61 reported eruptions since the mid-1500s have killed approximately 7000 people [START_REF] Voight | Historical eruptions of Merapi Volcano, Central Java, Indonesia, 1768-1998[END_REF].

Land use and agriculture Dry lands represent 23% of the cultivated area around Merapi. Most of them belong to the Tegalan type, i.e. dry fields that do not involve fire to enable cultivation on slopes as for the Ladang type. Food crops are dominant (e.g. peanuts, cassava), but commercial crops are also planted such as tobacco, chili, or fruits like salak.

Cultivation practices also include home gardens created within villages, providing families with extra food and income. The cultivation system is stratified and complex: cooking herbs, sweet potatoes, tomatoes and chili lay on the ground. Cassava plants provide roots and leaves that can both be eaten. Vines that produce beans, squash or edible berries are often cultivated on bamboo trellises around the edge, along with bananas. A few tall fruit trees provide protection or shade for the smaller plants.

Merapi's surroundings are essentially rural. Rice fields represent the main land cover (36%), followed by settlements, grasslands and dry lands. All the land is exploited, except Merapi's steepest slopes, which are covered by forests. Settlements also take up an important share of land use (25%), especially close to Yogyakarta. There is a contrast between Merapi's western flank, where rice fields are dominant, and its northern and eastern flanks, where dry lands are located.

Unquestionably, there is more rainfall on Merapi's western flank, providing the necessary conditions for rice production. Most farmers concentrate on small fields, modeling the landscape with terrace cultivation. Irrigation systems, widely developed in this area (41% of the cultivated area), contribute to the high productivity of rice fields.

C.2

Livestock

Source: data from Picquout, MIA VITA, 2012

Livestock is considered more as a food livelihood than an economical resource, as it represents important food stocks for local communities on Merapi slopes.

Cows represent the main livelihood through milk production and sale. Cow stocks are mostly spread out along the slopes where they can graze freely (Natural Reserve, Dove 2008), while sheep and goat stocks can be found everywhere. Most buffalos can be found on the western side of the volcano and are used as workforce in rice fields. Pigs stocks are not considered as they are very limited in the Merapi area.

Livestock is not proportional to the amount of people living in each village. Merapi's eastern slopes show a high ratio of livestock per inhabitant, whereas the southern and south-western sides have a poor ratio of livestock per inhabitant.

Saving livestock during volcanic crisis is a major concern for the inhabitants. Apart from the risk of immediate death, e.g. in pyroclastic flows, it is sometimes difficult to find clean grass and water for the cattle after ash fall events. Residents sometimes try to evacuate their animals when they evacuate themselves. If needed they are ready to face personal danger to continue feeding their animals in evacuated zones.

Livestock availability

Age distribution of people around Merapi

People over 55 are considered seniors in Indonesia (life expectancy at birth is 71.6 years). Elders, as well as children under 10 are particularly vulnerable. They represent 38% of the population around Merapi.

Elders, disabled people, and children require particular attention during evacuation: medical care and assistance for the elderly and adult supervision for the young. While schools can manage children's evacuation during school time, elders are less grouped and therefore harder to deal with. Both vulnerable groups need to be taken care of as quickly as possible when a threat is confirmed. Mentally and physically disabled people represent a significant part of the population on Merapi's western flank. A building's vulnerability depends on the material it is composed of, but also on the type of hazard that may strike it. During an eruption, pyroclastic flows destroy everything, whatever the construction material. However, pyroclastic surges do not impact all buildings in the same way: concrete buildings are more resistant. Architectural details of the structure also affect the way buildings resist destruction. For example, openings can let the flow go through, reducing its dynamic pressure on the building; however, the temperature of the surge and material carried within it may ignite any flammable material inside and cause fires.

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A traditional house made of wood and bamboo

A traditional house made of wood and bamboo A traditional house renovated with concrete walls A traditional house renovated with concrete walls

Building materials

Accumulation of ash on roofs can trigger collapse of buildings, especially if the ash is saturated by rain (up to 2000 kg/m³: volcanoes.usgs.gov/ash/build/ind ex.php). Main characteristics which affect the resistance to ash load are: the roof slope (flat roofs are more vulnerable), the roof span (bigger roof are more vulnerable), and the roof and building construction material. The road network is quite dense around Merapi. Main roads go straight up the volcano while secondary roads follow the volcano's contours and connect the main roads. Provincial and district road conditions are relatively good. Local roads linking each municipality are mostly asphalt and the roads in the southwestern part of the volcano are in the best condition. In most villages, road conditions are inversely proportional to the altitude: the higher they are, the lower their quality (Mei et al., 2013).

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Bimomartani

Types of buildings around Merapi

The tropical downpours contribute to fast degradation of the network, especially on unpaved roads. In addition, roads covered by ash are very slippy. As a result, the velocity of evacuation with vehicles is very limited. The maintenance of evacuation roads became a major issue for post-crisis management following the 2006 Merapi eruption [START_REF] Mei | Influence of the institutional and socio-economic context for responding to disasters: case study of the 1994 and 2006 eruptions of the Merapi Volcano, Indonesia[END_REF]. In response, local governments worked to enhance the quality of roads by paving them with asphalt. However, the condition of the roads degrades with time, especially because of trucks hauling volcanic materials [START_REF] Belizal | Quand l'aléa devient la ressource : l'activité d'extraction des matériaux volcaniques autour du volcan Merapi (Indonésie) dans la compréhension des risques locaux[END_REF].

Transportation Capacity

D.4

Motorcycles in a village at Merapi

In Indonesia, the most commonly used means of transport is the motorcycle, because of its low cost. On volcanoes, this phenomenon is accentuated because the population is poorer. Cars are mainly used in big cities, essentially by the middle and upper classes. The census conducted within the MIAVITA Project on the available means of local transport, recorded an average of one car for 43 inhabitants and one motorcycle for 5 inhabitants. This census led to the evaluation of each village's transportation capacities, measuring the ratio of inhabitants that could be evacuated with local means of transportation.

Buses and trucks are considered as being able to transport 30 people a minibus or and pick-up 10, a horse-drawn buggy 8, a car 6, and a motorcycle 3. The total transportation capacity is compared to the number of inhabitants to map the balance in transportation capacity.

Villages where the transportation capacity balance is 50% could only transport half of the local population. For villages with a balance of more than 100%, their transportation capacity would potentially enable the evacuation of the village's entire population.

The mapping of the transportation capacity balance displays a contrast between Merapi's northern and northwestern flanks and its southern flank. The population living on the northern flank is known to be more sedentary. Most inhabitants work in agriculture and sell their crops at markets close to their villages after having transported them by pickup. Accordingly, these modest income families do not invest much in means of transportation. Moreover, public transport networks (bus, taxi) are very poorly developed. Villages located along the southern and southeastern flanks have more means of transport, due to their proximity to larger towns (Yogyakarta and Surakarta), which generate employment and attract students. Vehicle dealers from the cities regularly visit the closest villages offering motorcycles on credit. Contrasts in access to means of transportation represent a major obstacle for the success of large-scale evacuation. Volcanic eruptions can result in a wide range of health impacts, arguably more varied than in any other kind of natural disaster. Medical services can expect an increase in the number of patients with respiratory symptoms, eye or skin irritation during and after an ashfall event. In the worst cases, exposure to volcanic ash may result in acute respiratory morbidity, especially in those with pre-existing respiratory disease. People can also be directly burnt by pyroclastic density currents or hit by lahars. In addition, the temporary disablement of municipal sanitation systems may lead to increased disease in affected areas. Around Merapi, more than 2 million people are exposed to ashfall hazard. Healthcare workers responding to the needs of volcanic risk management might therefore find themselves involved in scenarios as varied as disaster planning,

The location of health structures shows an irregular distribution around Merapi. Public hospitals are essentially located on the southern flank, close to main cities. Care centers and polyclinics are available in most dusuns.

There are only a few doctors along the slopes of Merapi. Most of them are located more than 12 km away from the dome, leaving the highest dusuns a doctor-free zone. surveillance, treating the injured, or advising on the health hazards (Hansell et al., 2006). Practicalities of risk management plans need to be thought in advance, and plans need to encompass medical care.

Mapping local healthcare structures (e.g. public hospitals or medical centres locally called PUSKESMAS) and heath personal is therefore an issue of great importance. a volcano under ''spiritual watch''

The role of cultural factors in shaping people's behavior in the face of volcanic hazards has been emphasized by anthropologists. The danger is filtered by an individual's perception of the world, which varies, -among other factors-, according to religious beliefs and community traditions. Around Merapi volcano, religious beliefs have animist, Hindu, Buddhist, Christian, and Muslim influences. The influence of religion is evident in the large proportion of people who think that actual and potential loss associated with volcanic eruptions are under the control of divine forces. Around Merapi, most places of worship are mosques. Christians are a minority. On the northern and eastern flanks, Christians are essentially Protestant, while they are mostly Catholic on its western flank. In the shadow of the main monotheist religions, spirit cults, ancestor worship, spirit healing and shamanistic forms ('dukunisme'), and mythical traditions enjoy much popular support. An eruption is often understood as an admonition from the supernatural world. As a result many people living on the Merapi flanks are not fearful. The permanent activity of the volcano has been totally integrated in people's daily life. Mount Merapi is personified: "Mbah Merapi" -Mbah means grandparent -belongs to the human world.

There are two cultural leaders in the traditional Javanese religion (Kejawen): the sultan of Yogyakarta and the Juru Kunci. The Juru Kunci is the key holder of the volcano. He communicates with the spirits who look after the mountain. On the slopes of Mt Merapi, local people put their trust in the local mystic Juru Kunci, Mbah Marijan, until he died in 2010. He was appointed by the sultan to carry out annual offerings to the volcano during the Labuhan ceremony. Many people attend the ceremonies, wishing to get a blessing from the Creator of the world. The distance between the village and the Juru Kunci's house at Kinahrejo influences the risk perception. Certainly, people living close to Kinahrejo trust the Juru Kunci above all else and feel protected, whereas people living further away from him, but at the same distance from the crater have less confidence in his supernatural power. The presence of the Juru Kunci's house at Kinahrejo partly explains the refusal of the inhabitants to evacuate before the 2006 eruption of Merapi, although the evacuation had been ordered by the authorities [START_REF] Lavigne | People's behaviour in the face of volcanic hazards; view from Javanese communities, Indonesia[END_REF].

However, the influence of the cultural factors on risk perception and on people's behaviour has progressively decreased since the 1990's [START_REF] Schlehe | Reinterpretation of mystical traditions -explanations of a volcanic eruption in Java[END_REF]. The sultan of Yogyakarta, who represents the link between the traditional and modernity, may have played a key role in this change. He has actively participated in the success of the evacuations in 2006, because he explained the necessity to evacuate the local people against the advice of the Juru Kunci. The death of the Juru Kunci during the 2010 eruption will certainly enhance this process.

D.7

Volcanic Risk Management After the 2006 eruption of Merapi, the hazard map was updated again intended for situations that had not been considered before (e.g. eruption in the central part of the summit, vertical ash column). This updated hazard map was used by local authorities as an input for contin-gency planning that took place in 2009 in each district surrounding the volcano.

Besides the scientific risk maps and zoning, the basic elements required for municipalities planning are information documents (at regional and local scale) gathering all the knowledge on hazard, elements at stake, prevention and emergency measures, urban master plans or simplified hazard zonation.

The most important information to be disseminated relates to the activity condition of the volcano. There are five observatory posts at Merapi: Kaliurang, Babadan, Ngepos, Jrakah and Selo. The condition and the morphology of the summit is reported from each post to CVGHM's Volcano Investigation and Technology Development Office (Balai Penyelidikan dan Pengembangan Teknologi Kegunungapian, or BPPTK) and to the Merapi Volcano Obsevatory (MVO, a section of BPPTK) in Yogyakarta, and then transmitted to CVGHM. The same information is also reported to local governments. Both CVGHM and BPPTK provide real-time observations of the volcanic activity, as well as closed-circuit video feeds on their website (http://vsi.esdm.go.id/).

Dr Surono, head of the Geological Agency Dr Surono, head of the Geological Agency

Monitoring room BPPTK Monitoring room BPPTK

D.8

Community-based disaster risk management

Socialization and CBDRM

At Merapi, most of the information is provided during socialization phase, a period of time, corresponding to the pre-alarm phase, during which a great effort is put into informing people about the volcano and its activity.

This socialization is achieved in the frame of a Community-Based Disaster Risk Management (CBDRM), which empowers communities with self-developed and culturally acceptable ways of coping with crises due to natural hazards. At Merapi the Obligatory Training for Volcano Eruption Disaster Countermeasure (OTVEDC or Wajib latih) for the community in KRB III is planned, prepared, and implemented by the community with the scientists and the government. It gathers together, among others, the PASAG Merapi (a 20-year old community organization on disaster preparedness) and Merapi Forum (a government representation on disaster management around Merapi).

The series of activities consists of workshops on module making, module trial, and facilitator training. Community meetings (Focus group discussions, or FGDs) are used to share experiences of past eruptions, identify problems during the crisis period, ensure that everybody knows the emergency plan, evacuation procedure, location of meeting points, etc. This activity generates three things: disaster risk mapping, standard operating procedure, and contingency plans at the village level.

JALIN Merapi is a community-based information network around Merapi. It integrates various media to quickly spread useful information on the volcano. At least four community radios (e.g. Radio Lintas Merapi at Deles, Klaten) are actively reporting information to their community, especially during volcanic crisis. JALIN MERAPI website has interactive features such as online messenger, discussion forum, maps and databases. Field updates are delivered by handy radio and SMS messages from mobile phone. Social media also play a key-role in disseminating information during volcanic crisis, especially Twitter.

Participatory 2D and 3D mapping

A series of participatory 2D sketch maps have been drawn by the local communities living on the Merapi flanks since the 2000's., under the umbrella of the NGO PASAG Merapi.

Participatory 3D Models (P3DM) basically consist of the building of stand-alone scaled relief models over which thematic layers of geographical information are overlapped. These 3-dimensional models raise local awareness of territories, provide stakeholders with powerfull mediums for land-use management and serve as effective community-organizing tools. In the frame of the MIA VITA project and in collaboration with the French NGO CCFD-Terre Solidaire, a P3DM has been built in 2011 in Ngargomulyo municipality on the western flank of Merapi. It contributed, first to precisely locate the damages during the 2010 eruption; second to delineate the trails and roads that have been used to evacuate. Crisis management in Indonesia is based on a top-down hierarchical organization. The National Disaster Management Agency (BAKORNAS/BNPB: Indonesian National Coordinating Agency for Disaster Management / Indonesian National Board for Disaster Management), founded in 1966, is a non-departmental body; its membership comprises up to 10 ministers and related governors. This agency's functions are to formulate, stipulate, and co-ordinate disaster management and its activities, pre-disaster, emergency response and post-disaster activities. To implement disaster management duties in Province and District/City regions, Regional Disaster Management Agencies (Satkorlak-Satlak/BPBD) have been established.

Focus Group Discussion

In the frame of the contingency plan approved in 2009, a scenario for Merapi's eruption was prepared for each district, and the roles of each institution involved were defined. The volcanic crisis management is based on the recommendations of the CVGHM, the institution in charge of assessing and monitoring volcanic activity in Indonesia. CVGHM provides four warning levels of volcanic activity. For each warning level recommendations are given for what people living on the volcano slopes are supposed to do (e.g. no need for concern, stand by for technical direction issued by CVGHM, prepare to evacuate, evacuate).

The BNPB and the BPBD are in charge of disseminating the alert level to the public following the established communication protocol. Evacuation orders are also given by BNPB and local governments at district level. However, if the danger is imminent, the BPPTK can use sirens to inform people directly to evacuate. Kentongan communication code

Aman Normal, safe O O O O O O ------O O O O O O Siap Ready O O -----O O -----O O Kejadian Khusus Special event O O O ----O O O ----O O O Kejadian Besar Major event O O O O O O O O ---O ---O O O O O O O O Bencana Alam Disaster O O O O O O O O O O O O O O O O O O O O O Kema an Death O O O -O O O O O O -O O O (repeated twice) 110°30'0"E 110°20'0"E 7°30'

Siren Siren

An early warning system network also provides a feeling of security. In 2002 at Merapi, over 70% of villagers thought that the traditional kentongan was an efficient system. However, only 46% of them were aware of the codes related to a volcanic eruption.

Merapi explosion 1 November 2010 Merapi explosion 1 November 2010

© Jeffe Castan, http://indonesia-zamrud-khatulistiwa.blogspot.com/ The Merapi 2010 eruption highlights that explosive and gravitational disintegration of a series of rapidly growing domes can generate a great diversity of eruptive processes and products. They are responsible for extensive and major impacts of contrasting nature and extent on the population, infrastructures and the environment. The 2010 eruption of Merapi was the most dramatic and intense eruptive episode since 1872. This multistage eruption produced an escalating sequence of distinct deposits from five main volcanic processes: ashfall, dome explosion, dome collapse, explosive eruption with column collapse, and debris flows (lahars, see plates G). Pyroclastic density currents (PDCs) were produced in all phases of this complex eruption.

Five main types of primary PDCs were produced during the 2010 Merapi eruption that are characterised by marked differences in distribution, dynamic characteristics, deposits, and impact. They are: 1) unconfined high-energy turbulent stratified PDCs (thereafter called high-energy PDC) formed from the explosion of rapidly growing lava domes; they caused the greatest and most extensive devastation and affected a broadly rectangular area about 3-4 km wide over a distance of 8.4 km; 2) valley-confined blockrich concentrated PDCs formed from gravitational collapse of the growing domes; they were responsible for many fatalities during the eruption and reached far up to 15.5 km in the Gendol valley and about 8.5 km in the Opak River; 3) overbank PDC lobes from the valley-confined block-rich concentrated PDCs that overspilled into other valleys; and 4) dilute PDCs that detached from the main valley-confined block-rich concentrated PDCs and propagated 50-400 m laterally from them in distal areas; and 5) valley-confined pumice-rich concentrated PDCs that formed from the collapse of explosive pumice-rich pyroclastic fountains and reached up to 15.5 km in the Gendol valley.

Pyroclastic density currents (PDCs) are variably hot mixtures of volcanic particles, gas, and ambient air that originate from eruption columns or dome collapses and flow mostly as a result of gravitational forces.

In some cases, sudden decompression of a pressurized lava dome or shallow-depth intrusion can generate a vertically or laterally expanding hot mixture of volcanic particles, gas, and ambient air that will form a high-energy dilute density current (high-energy pyroclastic surge) near the source before it transforms into a more concentrated PDC controlled by gravitational forces. Although there can be a continuum, there are two main types of PDCs: 1) dilute turbulent to non-turbulent PDCs that are less controlled by topography; and 2) concentrated less turbulent PDCs that interact differently with topography to behave either as valley-confined flows or overbank flows and that often generate on their margins and flow fronts, detached or decoupled dilute turbulent PDCs. The diversity of PDC deposits reflects the different PDC source processes as well as the complex and evolving processes of transport and deposition of the solid particles along their path. A total of 23 pyroclastic flows events were identified within the Gendol valley. Their total estimated deposit volume is ~36×106 m³.

The first eruptive phase occurred on October 26th, depositing 16.6% of the total volume. Phase 2 (Oct 30th -Nov 3rd) deposited 11.5% of the total. Phase 3 (Nov 4th -5th), which corresponds to the peak activity of the 2010 eruption, deposited more than 70% of the total volume. Late pyroclastic flows occurred during phase 4 (Nov 6th -23rd), depositing only 0.9% of the total volume. Complex, local-scale variations in flow dynamics and deposit architectures are apparent. The main factors that control the propagation of major flows and their potential hazards for overbanking were driven by:

(1) the rapid occurrence of several voluminous pyroclastic flows , associated with a steady filling of the landscape after the first two phases of the eruption;

(2) longitudinal changes in channel capacity following an increased sinuosity in the valley and decreased containment area;

(3) the effects of various triggering mechanisms (gravitational dome collapse, vertical or lateral dome explosions and column-collapse) and source materials involved for each pyroclastic flow generating event.

Succession of deposits (stratigraphy) along Gendol valley:

-mBLA1 : October 26th valley-filling deposits -mBLA2 and mBLA3 : October 29th to November 3rd deposits -mBLA4 and mBLA5 : November 4th -5th deposits, the only two main pyroclastic flow units identified in the distal reaches of the Gendol channel.

Valley-confined pyroclastic flow deposits mBLA: massive blocks, lapilli and ash csLA: cross-stratified lapilli and ash sLA: stratified lapilli and ash mA: massive ash

E.4

High The greatest and most extensive devastation of the 2010 Merapi eruption was imparted to infrastructure and the environment by the emplacement, on several occasions throughout the eruption, of unconfined high-energy turbulent stratified pyroclastic density currents (also called high-energy pyroclastic surge). They affected a broadly rectangular area of about 22 km², about 3-4 km wide over a distance of 8.4 km to the south of the crater.

The excessive growth rate of lava domes during the eruption, as well as the presence of rapidly-ascending, volatile-rich magma in the conduit led to their recurrent pressurization and explosive fragmentation. Very powerful explosions were focussed and directed laterally to the south by the horseshoe-shape, large, summit crater and the deep Gendol Breach canyon on 26 October, and particularly during the paroxysmal phase of the eruption on 5 November.

The expanding mass of hot volcanic fragments and gas was able to accelerate down the very steep slopes of Merapi's southern flank forming a stratified turbulent rapidly expanding hot current. In a previously unrecognized process for such small volumes of magma involved, the 2010 Merapi eruption underscores dramatically how major topographic features (the high transversal Kendil ridge, the deep Gendol River canyon) were able to strongly focused the PDC mass towards a major constriction, thereby limiting the loss of kinetic energy. This favoured elevated PDC velocities and high particle concentration, promoted overspilling of highly mobile PDCs across high ridges into other river valleys, and generated significant dynamic pressures (≥ 15 kPa) to distances of 6 km that caused total destruction of buildings and the forest.

The 5 November blast-like deposits consists of three units (U0, U1, U2) that correlate to explosions of an 11-minute sequence.

Both U1 and U2 show bi-partite layer stratigraphy with lower L1 and upper L2 layers. The erosive waxing flow head deposited L1 layer that is very coarse-grained, fines-poor, poorly-sorted and massive. The waning upper part and wake of the PDC deposited L2 layer that is much finer grained, fines-rich, moderately to well-sorted, with laminar to wavy stratification.

Field observations indicate that PDC height reached ~ 330 m with an internal velocity of ~ 100 m/s within 3 km from the source, comparable to observations at the most violent world historic volcanic blasts of the last 100 years such as Montagne Pelée (1902), Bezymianny (1956), Mount St. Helens (1980) and Soufrière Hills (1997). The Merapi 2010 eruption highlights that small-volume pressurized domes can generate devastating high-energy, high-velocity PDCs. This constitutes a credible high impact scenario for future eruptions at Merapi that pose particular monitoring, crisis response, and risk reduction challenges.

Sequence of deposits observed near Kinahrejo

E.5

Environmental impacts of high energy PDCs

Examples of environmental impacts of high energy PDCs

Environmental impacts of high energy PDCs

A vast area, about 223 km², between the Kuning river and the Woro river, was affected by PDCs. Vegetation was totally destroyed to slightly singed. This extends to Merapi Golf course (8.4 km distance), and is the largest affected area since 1874.

A. Map showing the distribution of high-energy PDC deposits from 26 October and 5 November 2010 and the typology of environmental impact (ground surface, trees). B. Overview of the impact on the forest of high-energy PDCs emplaced at 00:05 local time on 5 November 2010; Area of dense forest in the Kuning river as shown before the eruption on 11-09-2006 on high resolution GeoEye imagery (Google, 2012).

C. Same area after the eruption as shown on 11-06-2011 on high resolution GeoEye imagery (Google, 2012). Identifiable downed trees were traced in red to derive the flow orientation. The edge of the area of singed trees presents a crenulate outline, due to the effect of slight topography such as gullies and small hills and also due to the shape and typology of individual large groups of trees and patches of vegetation, which likely had different heat resistance and moisture content. D. Metre-sized fresh dense dome andesite and accidental boulders lifted and transported over some distance by the high-energy PDC and scattered on top of downed, abraded but uncharred trees at site with yellow star (Kuning River). E. Map of the orientation of trees (n=10 201) downed and transported by the high-energy PDCs (U1 and U2) of 5 November 2010 as it interacted with topographic features as a result of complex flow paths. Red arrows are field measurements, purple lines measurements were derived from satellite imagery.

Image Google Earth Image Google Earth

A temporal analysis of the 2010 event was conducted using datasets of WorldView-2 (Digital Globe)

The more diluted high-energy parts of the currents entered the Woro valley and spilled over either th -5 th In the village of Bronggang, approximately 13.5 km to the south of Merapi, 54 people who were in the process of evacuating from the village a few hours before the 5 November paroxysm were killed when dilute pyroclastic surges entered the village. Casualties suffered severe burns and were coated in a layer of fine ash [START_REF] Jenkins | The Merapi 2010 eruption: An interdisciplinary impact assessment methodology for studying pyroclastic density current dynamics[END_REF]. Fatalities were rapid and accompanied by severe skin or inhalation thermal injuries sustained from pyroclastic surges, rather than the result of direct trauma. Some corpses showed evidence of being caught in fires, while others were suggestive of death from the heat of the PDCs only.

The near total lethality for victims caught in dilute turbulent surges suggests that despite the low structural damage, temperatures of 250-300°C are not survivable by residents caught outside or inside buildings because of the ease with which hot ash could infiltrate through ubiquitous ventilation openings [START_REF] Jenkins | The Merapi 2010 eruption: An interdisciplinary impact assessment methodology for studying pyroclastic density current dynamics[END_REF].

Based on BNPB data, a total of 277 people were directly or indirectly injured during the 2010 eruption. Most of them were located on the western and southern flanks of the volcano, where the hazard was most intense. Slightly injured people located on the western flank were affected by respiratory issues due to their exposure to volcanic ash, as the ash cloud migrated westward by the winds during the eruption.

© AP, Achmad Ibrahim 2010 More than 1200 destroyed buildings were recorded following the November 5th explosion and associated pyroclastic flows, with >60% of these buildings completely removed from their foundations. Thankfully, the PDCs effects were local as it was contained within a few valleys. Around the pyroclastic flow path, 245 houses lost their roofs in the blast. Within the affected area, only 628 houses were unscathed. Damage to buildings decreased with distance from the summit, illustrating the reduction of pressure as the pyroclastic density current flowed down, as shown by those pictures, taken in the Opak channel.The first one (a) is located at a distance of 5.8 km from the Merapi. The pressure value due to PDC was superior to 10 kPa. The second one (b) was located at 6.10 km and suffered a dynamic pressure between 10 and 5 kPa. The third one (c) was situated at 6.5 km and was subjected to a dynamic pressure between 5 and 2 kPa. The last picture (d) was located at 7 km from the volcano and the pressure was less than 1 kPa.

Healing victims in a hospital Healing victims in a hospital

Bronggang

! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! !! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! !! ! ! !! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! !!! !! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! !! ! !! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! !! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! !! ! !!! ! ! ! ! ! ! ! ! ! ! !!! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! !! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !!! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !!!! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! !! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! !! ! ! !! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! !! ! ! ! ! ! ! ! !! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! !! !! ! !! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! !!! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! 110°28'0"E 110°26'0"E 7°36'

Shelter Types

F.4

110°40'0"E 110°30'0"E 110°20'0"E 110°10'0"E 7°30'0"S 7°40'0"S 7°50'0"S ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! Selo Secang Sruwen Klaten Sleman Muntilan Kartosuro Bronggang Kaliurang Yogyakarta Bimomartani Ngargomulyo Source: data from Mei, 2013
Several types of evacuation shelters were set up or improvised during the 2010 crisis:

-Official shelters, such as schools or official buildings, were provided by the government.

Local authorities recorded and registered the refugees.

-Community-based shelters were provided by individuals or communities from other regions (due to the large number of community-based shelters, local authorities often did not record the refugees). Support and help were provided by NGOs and communities from beyond the area affected by the eruption.

-Relative-based shelters were provided by relatives/families. It is estimated that most of the population within the 20 km radius who did not evacuate to official shelters went to community-based, and/or relative-based shelters.

Because of the lack of space and comfort in shelters, people tended to stay at home during the day and come back to evacuation shelter in the evening (Mei and Lavigne, 2013). 'The conditions of shelters were very unpleasant, but at the time, what was most important for us was our safety. We brought nothing except the clothes on our backs. We were lucky to be able to run away from danger. '

Official shelter

Sutirejo, a 78 year-old woman from Turgo, interviewed on 26 June 2010 by E.T.W. Mei

Shelter Attendance

F.5

7°30'0"S 7°40'0"S 7°50'0"S 110°40'0"E 110°30'0"E 110°20'0"E 110°40'0"E 110°30'0"E 110°20'0"E 110°10'0"E 110°30'0"E 110°20'0"E 110°10'0"E 7°30'0"S 7°40'0"S 7°50'0"S ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! Selo Secang Sruwen Klaten Sleman Muntilan Kartosuro Bronggang Kaliurang Ngargomulyo Yogyakarta Bimomartani ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! 110°40'0"E 1 2 5 0 5 0 0 1 0 0 0 5 0 0 0 1 0 0 0 0 2 0 0 0 0 Provincial road

Location and attendance of refugee camps during and after the 2010 eruption

At the beginning of the 2010 eruption, approximately twenty refugee camps were prepared to accommodate people living in KRB III municipalities as described in the 2009 contingency plan. These camps, located less than 20 km from the summit, welcomed the first wave of refugees (~22,000 people) on 26 October after the first volcanic explosion. The number of evacuees reached 53,048 on 30 October. The organization of refugee camps worked smoothly in the early period of displacement. When the restricted zone was extended on 4-5 November, the number of refugees exponentially increased while no refugee camps had been prepared beyond 20 km. Therefore, most of the evacuees after the main explosion were settled in emergency in public buildings (schools, hospitals, stadiums, village halls, and universities) or even residents' houses or yards. On 13 November there were at least 600 camps registered by BNPB, scattered around Sleman, Magelang, Boyolali, Klaten and several other Districts in Central Java Province and Yogyakarta Special Region Province. Despite the evacuation order to clear the 20 km radius 10 days earlier, the highest number of refugees way reached on 14 November (399,403), due to insufficient preparedness in handling the evacuation and refugees' movements from one camp to another (sometimes several times). The number of refugees then decreased significantly when the local authorities decreased the radius of the restricted zone to 10 km. People from villages that were still habitable went home for good. On 9 December less than 20,000 people were still recorded in the refugee camps.

F.6

Population Behaviors During the Crisis Most of inhabitants evacuated only when the first pyroclastic flows were reported on 26 October despite the evacuation order given earlier on 25 October. This evacuation may be classified as "evacuation when hazard is imminent" a phenomena that is common at Merapi. As in previous eruptions, people wait to evacuate until a pyroclastic flow or ash fall event has taken place, even though the government had previously informed them that the volcano was already at its highest warning level.

Despite evacuation orders and efforts of local authorities to evacuate people, some residents were reluctant to leave their villages. Refusal to evacuate was mostly due to people's perception of the volcano, cultural beliefs and socio-economic conditions. This refusal led to casualties, i.e. the evacuation refusal of Marijan (Merapi volcano's gatekeeper) and his followers led to the deaths of thirty-five people in the village of Kinahrejo (5 km from the summit). Along the southern flank of the volcano, evacuation refusals were mostly conditioned by trust in the gatekeeper and the feeling of being protected by his presence, even though Marijan suggested to people not to follow his decision to stay in the village. However, people living far away from the gatekeeper's village opted not to leave their house because of their poor understanding of volcanic processes.

Others stayed in their village to look after their livestock.

'When we had to evacuate, most residents did not know where they had to go to except to go away from Merapi. '

Sutaji, head of Bronggang-Suruh village, interviewed in December 2011

During the paroxysmal eruption on the night of 4-5 November, people self evacuated. Without detailed instructions, people tried to escape by themselves, but many did not know exactly where to go. Volcanic eruptions that eject ash into the atmosphere represent a threat to the safety of air traffic. Tephra is very abrasive to the cabin, and ash accumulates in the engines generating engine failure. On June 24th, 1982, a British Airways Boeing 747-236B (Flight 9) flew through the ash cloud from the Mount Galunggung eruption (in West Java), resulting in the failure of all four engines. Since then, international rules restrict air traffic in case of a threat.

Under normal circumstances, 90 flights are programmed every day in Adisucipto Airport, with an average 11,500 passengers per day. For the first time, Merapi eruptions resulted in major disruptions of air traffic in Yogyakarta, which has resulted in a paralysis of the city's activities. During the volcanic crisis, about 2,000 flights were canceled, comprising 1,350 flights during the closure of the airport for 15 days, and 600 flights due to a lack of a sufficient number of reservations after its reopening. Some companies like Garuda Indonesia suspended or transferred their flights to other airports, whereas the low cost carriers like Lion Air continued to fly despite the risks involved.

The eruption of Merapi was fatal to Mandala Airlines, which encountered financial problems since 2010 and declared bankruptcy on 13 January 2011.

The eruption disrupted the pilgrimage to Mecca for thousands of Muslims. Surakarta Airport is the starting point of the pilgrimage for the Central Java province. As it was also under volcanic ash threat, all international flights to and from Surakarta were suspended from November 5th to 19th. Nevertheless, the organizers were able to cope with the crisis by relocating the departure airport for the pilgrimage.

Globally, "only" 2,520 flights were cancelled in Java in 2010 against 110,000 flights in Europe due to the Eyjafjallajökull eruption. Nonetheless, the disturbances lasted longer (~2 months); different strategies were adopted, e.g. decisions to clean the runway, to re-launch flight activities by bypassing the cloud or by flying aircrafts at a different altitude, etc. The precautionary principle ruled differently in Indonesia. Indonesian airlines are economically weak, leading some of them to fly at risk instead of cancelling their flights. In the Putih River, 55 events occurred during the first hydrological year (October to April). Over the same period, rivers Boyong and Gendol in the southern flank, and Ladon and Apu in the northern flank experienced between 20 and 30 lahar events each. Less than 20 lahar events were recorded in the other rivers. At least four factors may explain why most of the first post-eruptive lahars were preferentially triggered in western rivers: @ Moch Muzani, BPPTK (i) Rainfall amount from January to April is twice as high on the western flank of the volcano (>4000 mm at Babadan) than on the southern flank (2000 mm at Kaliurang); (ii) The watershed of rivers Putih and Pabelan is larger than that of rivers in southern flank; (iii) Fallout tephra up to 20 × 106 m³ were mainly deposited on the western slope of Merapi, due to the dominant wind direction during the eruption. (iv) Pyroclastic-flow deposits in rivers Gendol and Opak remained very hot for months (even years) after the eruption, thereby preventing the flow of rainwater that evaporated instantly on contact with the ground.

More than 3,000 people became homeless after the first rainy season following the 2010 eruption, as 860 houses were buried or partially destroyed by lahars, mainly on the rivers Putih, Opak and Gendol. Crops, rice fields, irrigation arroyos, and road networks were also strongly affected by lahars on both the western and southern slopes. The road network was strongly affected by the destruction of bridges and dams crossing the river. One can notice the ~5m thick deposits accumulated upstream this sabo dam and bridge.

Sabo dams trap sediments until they are obstructed by the successive deposits. Sabo dams and bridges crossing the numerous rivers flowing down Merapi were quickly destroyed by lahars after the 2010 eruption. From December 2010 to April 2011, 14 sabo dams and 21 bridges were filled or swept away along the western and southern flanks of Merapi. The example of the SE-RD5 sabo dam is quite repre-sentative. Its construction across the Senowo River ended in 2009. This state-of-the-art sabo dam shows larger outlets than usual and is not obstructed by a road. However, this sabo dam was not designed to sustain more than 4 to 5 lahars a year. The Senowo River was affected by 13 lahars until March 2011, and so filled up quickly. Blocks from the first lahars got stuck and clogged up the sabo dam, preventing any flow from going through. Tamanagung is a village located 20 km west of Merapi's crater, along the Pabelan River.

In Tamanagung, a dozen houses were built on an old terrace 5m above the Pabelan's 47 m wide and 21 m deep riverbed.

On March 30th, 2011, a series of lahars from the Pabelan's tributaries converged (Trising, Senowo, etc.) upstream of Tamanagung, forming a large single lahar flowing down the Pabelan. When it reached Tamanagung, constrained by the sinuosity of the riverbed, it overflowed the inhabited river terrace, burying houses under a 2 m high deposit, while the twin bridges of the Yogyakarta-Semarang highway collapsed.

The lahar debit was estimated at more than 1.800 m3/s at the twin bridges. At this precise location, the cross-section is about 490 m², and the velocity of the flow was estimated to be of 3.7 m/s. In the Putih River, lahars began during the November 5th, 2010 eruption. Eighteen lahars were recorded until January 3rd, 2011. Located 20 km southwest of the crater, Sirahan is a village on the banks of the Putih, whose riverbed does not exceed a 1.5 m depth for a 3 m width. From November to December 2010, lahars left over 5 m of deposits extending the riverbed to a 10 m width. Early January 2011, local communities built a dyke on the riverbed, leading to its elevation above the inhabited level by the quick accumulation of volcanic material transported by the river.

On January 9th, 2011, a powerful 4 m thick lahar overflowed the dyke flooding Sirahan. The river eroded a new channel of 3.5 m depth across the inhabited area and the rice fields, until it converged back to the Putih, hundreds of meters downstream. This change of riverbed occurred due to the 25 lahars that flowed down the Putih between January 2011 and the end of the rainy season, in late May 2011. By then, the riverbed was 30 m wide and 7 m higher than before the eruption.

These lahars generated important structural damage in Sirahan: 37 houses were destroyed, 217 damaged, 30 ha of arable land was buried under 3 m of lahar deposits. Most houses destroyed by the May 1st, 2011 lahar were located close to Gendol's small riverbed (1.5 m deep by 3 m wide). This lahar did not meander around Ngerdi, but overflowed, crossing the village of Kayen, as well as its rice fields. Fifty one houses were damaged.

Houses being progressively buried by deposits along the Putih

Houses being progressively buried by deposits along the Putih

After leaving over 40,000 m² of deposits, the river eroded a 1.5 m deep channel in the village. One day after the lahar, the Gendol was divided into two flows: one following the original riverbed, the other crossing the village. The activity in secondary sites remained, but is still far below that of the main sites. Daily extraction volumes per site never exceed 300 m3, and the lowest limit is of 40 m3. Secondary sites where at least 100 m3 are extracted daily are located along a major axis (Jumoyo), or are old sites that were not too severely damaged by pyroclastic flows in 2010 (Kaliurang, Sudimoro, Balerante). In 2012, the activity was still low here, but could intensify along the Putih, where lahars regularly renew the resource. On the other hand, in Balerante or along the Bedeng, the activity is solely maintained by local inhabitants.

Minor sites are located along rivers from the Putih to the Woro, except along the Batang. These older sites were rehabilitated after the 2010 eruption (Srumbung in the Putih; Boyong, Dam Kuning and Pondokrejo in the Krasak). Sales are mainly local, as these sites are far from the main roads.

Irregular sites are not used every day. Rarely more than three to five trucks can be seen there. Their accessibility is poor, especially along the Pabelan River where most bridges were destroyed. People prefer exploiting sites along the Gendol, which is much more accessible.

Extraction of lahar deposits in 2011

Map of lahar modelling

Boyong-Code river Monitoring associated with geologic disciplines includes the quantification of the morphology evolution of the summit area, as well as observation of the process of rock alteration due to gas emissions and exposure to high temperatures. At the time of the eruption, observation involves determining the volume and distribution of erupted material, as well as the eruption chronology based on the stratigraphy of deposit material.

Seismic monitoring at Merapi is a combination of short-period (SP) and broadband seismic stations (BB). A total of 9 stations installed around Merapi consists of 4 SP stations and 5 BB stations. One station is installed about 65 km south of Merapi as a reference of regional seismic activity.

SP data are transmitted by using an analog VHF radio and are digitized at BPPTKG office. BB stations use CMG-40TD Guralp seismometers. Data is transmitted by using a digital system with a frequency of 5 GHz via TCP/IP protocol.

DOMERAPI project has also installed a small aperture seismic array (Antenna) in Pasar Bubar to locate seismic sources associated with magma intrusion.

EDM

EDM instruments (Electronic Distance Measurements) estimate the radial deformation through the measurement of the distance between a reference position on the slopes (observatory post) and a fixed target (reflector) at the summit. There are 10 units reflectors installed around the flank as measured from 6 positions which 4 positions in the observatory posts (Kaliurang, Babadan, Jrakah, and Selo), in Deles (Southeast sector), and in Mriyan (East sector).

TILTMETER

In the long and medium term, monitoring ground deformation by tiltmeter allows observation of subtle inflationdeflation processes associated with magmatic activity of the volcano. Tiltmeter sensors are AppliedGeomechanics 701-2A, which have a resolution of 0.1 μrad and a sampling speed of 1 sample per 5 minutes. Borehole tiltmeters were installed by DOMERAPI as elements of the Multiparameter stations. The sampling rate is 100 samples per second.

GPS + GLONASS

On volcanoes, accuracy of a few centimeters or less is necessary for detecting the build up of stress and pressure caused by magma rising toward the ground surface. To obtain this accuracy, realtime GPS is used in 9 permanent stations, 4 of them are installed by BPPTKG (in BPPTKG office as reference station, Deles, Grawah, and Klatakan), and 5 stations are installed by DOMERAPI project (in Selo, Babadan, Jrakah, Plawangan, and Pasar Bubar). Data is being transmitted and processed automatically at BPPTKG office.

Geochemical monitoring is done by measuring regularly the gas composition of fumaroles in the crater area. The analysis is performed at BPPTKG by chromatography, spectrophotometry, and volumetry. Decrease in water vapor and increase in other volcanic gas content increase is an indication of magma supply. SO2 plume flux is surveyed with Differential Optical Absorption UV Spectroscopy (DOAS) in scanning mode, using two automated stations.

H.2

Seismometer WebObs: An integrated web-based system for observatories (1) Seismological and volcanological observatories have common needs and often common practical problems for multi disciplinary data monitoring applications. In fact, access to integrated data in real-time and estimation of measurements uncertainties are keys for an efficient interpretation and decision making. But instrument variety, data sampling, heterogeneity of acquisition systems lead to difficulties that may hinder crisis management. We faced this problem in the IPGP overseas observatories and since 2001, we developed an operational system that attempts to answer these questions in the context of a multi-instrumental observatory [Beauducel and Lafon, 2014].

The WebObs system, based on open-source scripts, proposes:

In 2013, the DOMERAPI project installed WebObs at BPPTKG. At the time of the printout, it includes GPS automatic process and plots, multi-parameter and transmission stations equipment logs.

an extended database for networks management, stations and sensors (maps, station file with log history, technical characteristics, meta-data, photos and associated documents); web-form interfaces for manual data input/editing and export (like seismic bulletin, geochemical analysis, repetition deformation measurements, ...); routine data processing with dedicated automatic scripts for each technique, production of validated data outputs, static graphs on preset moving time intervals, possible e-mail alarms; acquisition processes, stations and individual sensors status automatic check for technical control.

H.4

Source: Beauducel et al., WebObs/IPGP, 2014

Increasing Hazards Awareness

H.7

Before the 2010 eruption of Merapi, several tools were already used to develop hazard awareness of the local people. Community education on volcanic disasters (e.g., socialization, posters, pamphlets, signposts, evacuation drills, etc.) was conducted collectively by the members of BPPTK, local authorities, academic institutions and NGOs. However these activities were only conducted with communities from the villages located within the official hazard zone of KRB III and II. To prevent future loss of life during unusually large eruptions, disaster risk education and preparation are presently conducted for all Merapi danger zones, including KRB I (lahar-prone zone).

Evacuation routes signpost Furthermore, additional hazard signs have been set up in all hazard zones, as well as evacuation guidance and indications of meeting points at the time of crisis. The new Merapi Museum also provides useful information to tourists, including comics on precursory signs of an eruption.

Poster from

  preface (i) The MIA VITA Project (Mitigate and assess risk from volcanic impact on terrain and human activities -2008-2013) was financed by the European Commission under the 7th Framework Programme for Research and Technological Development, Area "Environment", Activity 6.1 "Climate Change, Pollution and Risks". It was led by the French Bureau de Recherches Géologiques et Minières (BRGM -Grant agreement no. 211393

IntroductionA

  Merapi volcano from rice fields © F. Lavigne, 2012 Distribution of recent Large earthquakes in Indonesia (2008-2014) subduction process and island arc Source: Trista L. Thornberry-Ehrlich, Colorado State University, http://www.nature.nps.gov/.

  Volcanoes in Indonesia are part of the Pacific Ring of Fire. The Indonesian archipelago contains about 130 active volcanoes, which is more than any other country. About 76 of them have erupted in historical times. It contains some of the world's most famous volcanoes like Toba, Krakatau, Tambora, and Merapi. The most active volcanoes of the country after Merapi are Semeru and Kelut, both on East Java. Semeru (3676 m) has erupted continuously , and lava flows twice a century on average. Since AD 1000, Kelut has erupted more than 30 times, of which the largest eruption was at scale 5 on the Volcanic Explosivity Index (VEI, defined by[START_REF] Newhall | The volcanic explosivity index (VEI) an estimate of explosive magnitude for historical volcanism[END_REF]. It has been responsible for thousands of deaths on Java island, mainly due to the sudden draining of its crater lake and subsequent lahars. Its last major eruption on 13 February 2014 sent a column of ash 25 km high, killed 2 people and forced 200,000 people to evacuate. best known for their catastrophic eruptions with worldwide climatic impacts. Mount Tambora was notable for the most violent eruption in recorded history in April 1815. The explosion was heard on Sumatra island more than 2000 km away. Volcanic ash falls were observed almost everywhere in Indonesia. Most deaths from the eruption were from starvation and disease, as the ashfall ruined agricultural productivity in Sumbawa and Lombok. The death toll was at least 71,000 people.

  Out of the 1.1 million people living on the flanks of the active Merapi volcano, more than half are at high risk in areas prone to pyroclastic flows, surges, and lahars. People accept the risk because of the rich volcanic soil. Over time, volcanic deposits can develop into some of the richest agricultural lands on Earth. Mapping human population density around Merapi reveals an increase in density from the summit to the base of the volcano's flanks. Within a 10 km radius of the summit, the most hazardous area, population densities are of an average 764 inhabitants per square kilometer. Some highly populated villages (> 1500 inhab./km²) settled within a 5 km radius area are very exposed to the volcanic hazards.Their vulnerability is increased because the local people must use steep, damaged roads to flee. On the southern flank, the villages climb the volcano slopes up to 1150 m a.s.l. around the Gendol and the Woro rivers. Further south, population densities increase considerably between 200 and 400 m high, due to the attractive proximity of Yogyakarta city. Yogyakarta urban area is located on a highly populated, fluvio-volcanic plain. The city is the political, economic, social and cultural center of the special Province of Yogyakarta. For 50 years, this city of over 1 million inhabitants has attracted people from the surrounding overcrowded rural areas. In order to preserve the productive tilled lands and irrigation networks around the city, the government has attempted to control the urban growth. The guidelines in the master plan have restricted the extension of the city. However for the last 30 years,

B

  Growing dome in Merapi crater © J. Morin, February 2013B.1Geology of Merapi VolcanoSource: data and map from[START_REF] Gertisser | The geological evolution of Merapi volcano, Central Java, Indonesia[END_REF]

  Main site (> 4000 m 3 /day) Secondary site (800 to 1000 m 3 /day) Peripheral site (< 800 m 3 /day) Minor site (< 800 m 3 /day) Closed site > 2000 m 3 /day < 2000 m 3 /day Unknown volume these activities for income. The sand is used as building material, while blocks are sold as raw material for sculpture workshops and building. The most accessible areas for extraction are the beds of the main rivers, which are regularly fed by PDCs and lahars coming from the upper slopes of Merapi. While sand and blocks were mostly extracted along the Putih in the early 2000s, after the 2006 eruption and consecutive lahars, the extraction activity migrated to the Gendol, on southern flank.

  N Ngargo N N N N N a o ga Ngargo N Ngarg Ngargomulyo

  et al., 2013 Daily count of seismicity recorded prior of and during 2010 eruption Comparison between SO2 fluxes and RSAM data VT = Volcano-tectonic; MP = Multiphase (=Hybrid earthquake); LF = low-frequency; Rockf = Rockfall earthquakes; Pyroclastic F = Pyroclastic flows; RSAM = Real-time Seismic Amplitude Measurement (Source:[START_REF] Surono | The 2010 explosive eruption of Java's Merapi volcano -A 100 year' event[END_REF]

  Source: data and maps fromCharbonnier et al., 2013 and[START_REF] Komorowski | Paroxysmal dome explosion during the Merapi 2010 eruption: Processes and facies relationships of associated high-energy pyroclastic density currents[END_REF]

  , photos and maps from[START_REF] Komorowski | Paroxysmal dome explosion during the Merapi 2010 eruption: Processes and facies relationships of associated high-energy pyroclastic density currents[END_REF]

F

  from Picquout, MIA VITA Based on BNPB (National Board for Disaster Management) data, 367 people were killed during the 2010 eruption, including 200 directly caused by Pyroclastic Density Currents (PDCs). Most fatalities were, therefore, located on Merapi's southern flank. The initial explosive eruption of Merapi on 26 October 2010 killed 38 people at Kinahrejo village, including Mbah Marijan the spiritual key holder of Merapi.

  Impact of Pyroclastic flows on houses Damaged and destroyed houses around Merapi and in Opak RiverSources: data from Picquout, MIA VITA, at the Dusun level; Jenkins et al., 2013, at small scale ; all pictures S. Jenkins. 19 November-3 December. The radius was reduced to 15 km for the sector between the Boyong and Gendol rivers, 10 km for the rest of Sleman District, 10 km for Magelang District and Klaten District and 5 km for Boyolali District. The wider extent of restricted zones to the south is due to the morphological patterns of Merapi summit which is a horseshoe opened southward.

  and Lavigne, 2013; Mei et al., 2013

  Refer to the map on plate A-3 to locate the rivers. from E. De Bélizal, MIAVITA 2012.

Filled

  photo © E. De Bélizal, 2011.

  .De Bélizal et al. 2013 A phenomenon similar to the one that occurred in Sirahan took place in Ngerdi: lahars caused the river to change paths (defluviation).

  and map from De Bélizal, MIAVITA 2012 The significant amount of pyroclastic material combined with frequent lahars following the 2010 eruption completely changed the spatial organization of the extraction sites around Merapi. New extraction sites opened while others closed. Globally, the volume of extracted material decreased after the eruption. But this was soon counterbalanced, with the reintroduction of large tipper trucks and the use of mechanical diggers, recently authorized by the government. The hierarchical organization of extraction sites showed the emergence of a new extraction basin downstream of the Gendol River after 2010.

  Satgas MitigasiBencana Merapi (SMBM) NGO: «Danger, cold lahars -Move away from the river!»

Volcanological Posts 7° 30' S 7° 40' S 7° 35' S 110° 20' E 110° 25' E 110° 30' E 110° 35' E

	Several periods of growth and
	destruction of the Merapi stratocone
	have preceded the present volcano.
	Three	edifices	have	been
	distinguished by
					Cepogo pogo Cepogo
					G. Bibi G. Bibi	Boyolali Boyolali Boyolali
					Merapi Merapi
					Muntilan M Muntilan
					G. Turgo G. Turgo	G. Plawangan G. Plawangan
					Salam Salam
				B J	Babadan Jrakah	k k P P Pakem
				K	Kaliurang
				N	Ngepos
				S	Selo	Sleman
					Klaten

Date of eruption VEI Volume ejected (million m 3 ) Victims Injured Evacuated or made homeless

	1872	4		200
	1904	2		16	45	3 000
	1920	2	5	35		1 000
	1930	3	26	1 369		13,000
	1954	2	20	64	57	3 000
	1961	3	29.4	6	6	8 000
	1994	2	3.5	64	500	6 026
	1998	2			314	6 000
	2006	1	13.3	2		22,253
	2010	4	150	341	368	1 300,000

Sources:

Thouret et al. 2010; Mei

and Lavigne 2012 Major Merapi eruptions since 1872 7°30'0"S 7°40'0"S 110°30'0"E 110°20'0"E

	Pyroclastic Density Currents
	© M. Mongin, 1994
	Ash
	© Worldvision.com.au 2011
	Lahars

Source: adapted from

[START_REF] Komorowski | Paroxysmal dome explosion during the Merapi 2010 eruption: Processes and facies relationships of associated high-energy pyroclastic density currents[END_REF]

0"E 110°20'0"E 7°30'0"S 7°40'0"S

			© E. de Belizal, 2011
	Livestock in 2010
				Selo				Selo
			Ngargomulyo					Ngargomulyo
	Muntilan				Muntilan
				Kaliurang				Kaliurang
	Sleman				Bronggang	Sleman			Bronggang	Livestock per 100 people
										< 10
	110°20'0"E 0	2	4 Km	Bimomartani	110°30'0"E Sheep and goats Cow Buffalo one dot for 10 units	0	2	4 Km	Bimomartani 110°30'10 -17 -26 -51 -100 101 -200 > 200

Resident with his cow on Merapi Resident with his cow on Merapi

	© E. De Bélizal 2011

Evacuation of cattle due to a lahar warning Evacuation of cattle due to a lahar warning C.3

	Block and Sand Mining
			Main extraction
			basin
			Main road
			River
	0	2	4	8 Km
				Source: De Bélizal, 2012.

Coordinator of evacuation may be different in each district

  Coordination of evacuations is handled by one or more institutions: the Indonesian Department of Transportation, the Departement of Public Works, and the Army. Official transport such as busses, trucks or cars are provided by the Indonesian Department of Transportation, Department of Health, Social Department, Army, Police, by the Sub-district Government, and/or by Non-Government Organizations (NGOs) and by a number of other organizations and volunteers. In addition, private vehicles are used.Kentongans in the village of Turgo

							D.10
	Early Warning Systems
				Warning levels for volcanic
				eruptions in Indonesia Siren Kentongan House Security office	Evacuation route	River
					Volcanic	Meaning
					activity
					level
				I	AKTIF	Normal (or Base) level,
					NORMAL	non-eruptive state
				II	WASPADA	Attention (or Advisory) level,
						"starting unrest" e i t i r T	g n i l i l
				III	SIAGA	Pre-alarm (or Watch) level, rapid increase of precursors and on e S k o k d o L e d e L
						increased potentiality of eruption
				IV	AWAS	Alarm (or Warning) level, the
						eruption is imminent or happening
				Organization of public authorities during volcanic crisis S u n g a i B o y o n g
							Regional Disaster Management Agency
						(as crisis management coordinator at district level)
							Adapted from Kadarisman, 2010
						(Magelang district: Department of Transportation, Sleman district: Department of Public Work
							Klaten disctrict: Army, Boyolali: Army)
	Early warning system diagram in Indonesia
					Official transport (bus, truck, car) provided by:	Organization of population	Organization on Refuge
			National Disaster Management Agency		-Dept. of Transportation* -Army -Police	evacuation in the village of origin: (at meeting points)	camp: -Social department* -Sub-district employee
	Ministry of Energy and Mineral	Provincial Disaster	warning	-Dept. of Health -Sub-district office	-Head of municipality*	-Red Cross -Department of health
	Resources	Management Agency	communication	-Social Department	-Head of village	-Department of public work
					-NGO		-Civil service (Sat Pol PP)	-Disaster Corps (Tagana)
					-Other organization for volunteers	-Disaster corps (Tagana)	-Army
	Vulcanological Survey of Indonesia Merapi Volcano	Regional Disaster Management Agency Sub-district Level		Local transport (community capacity of evacuation): Motorcycle, car, pickup, car, truck	-Army -Search and Rescue Board -Red Cross -Local organizations -Local and international NGOs	-Local and international NGOs -Civil service (Sat Pol PP) -Police -Boy scout -Volunteer
	Observatory	Operational Unit
						Evacuation of victim
	Related Institution/ Agencies	Press	Village Level Operational Unit	Community		or people left in the village: Army -Special Forces Command*
			Observatory Station		* = Coordinator

© Source:

Mei et al., 2013

Source: data from

Mei et al., 2013

November -00:11 to ~02:30

	The earliest signs of Merapi summit's	the greater frequency of earthquakes,
	inflation following the 2006 eruption	the amplitude of released seismic
	began in November 2009. Early indica-tions of increased seismic activity included swarms of volcano-tectonic	energy, the rapid and large deformation (from EDM), and significant gas emissions were evidence that a larger	26 to 29 October Initial phreatomagmatic vent-clearing phase in which 38 people who refused to
	(VT) earthquakes.	volume of magma was involved.	evacuate were killed and more than 150
	The period from 20 September until the	On 21 October CVGHM raised the alert from level II to III. On 25 October at	buildings damaged across an area of approximately 7.5km²
	initial explosive eruption on 26 October was marked by a dramatic increase in all	06:00 local time, after seismicity and deformation increased to unpre-	29 October to 4 November An escalating phase of rapid dome
	monitored parameters. Prior to the 26	cedented levels, the alert was raised to	growth and collapse with PDCs of
	October eruption, the seismicity rate	its highest level IV and CVGHM warned	increasing runout reaching to 12km
	increased and SO2 fluxes reached levels comparable to the highest rates obser-ved during past eruptions (from 1992 to 2007). Compared to previous eruptions,	that there was a high probability of a large explosive eruption, greater in magnitude than those of recent history.	5 November -00:01 to 00:11 Explosion of the dome and upper sealed conduit with associated laterally directed turbulent PDC that felled trees and
			damaged more than 1,300 buildings
			within a 22km² sector of the south flank
			and produced block-rich valley-confined
			PDCs that travelled more than 15km
			from the crater
			5 Retrogressive collapse of the remaining
			dome and upper edifice producing PDCs
			that travelled more than 16km (15.5km
			radius) into the Gendol river channel,
			with flow overspill and dilute surges
			extending up to 200m from the parent
			flow and killing more than 120 people
			5 November -00:11 to ~03:00
			Fountain and subplinian convective
			column collapse that produced concen-
			trated scoria-and pumice-rich confined
			PDCs to 13km and 16km in the Gendol
			channel, respectively

Top: Overview of SO2 degassing during the 2010 Merapi volcano eruption (UTC time) Bottom: seismic data (RSAM) computed for the Plawangan station (6km from the summit). Source:

[START_REF] Surono | The 2010 explosive eruption of Java's Merapi volcano -A 100 year' event[END_REF]

  -energy Pyroclastic Density Currents

Source: Komorowski et al., 2013; Jenkins et al., 2013 © CVGHM 2010 & 2011.

Nov 5-13 Nov 14-19 Nov 19 Nov -3 Dec

	Volcanic crisis periods and change of alert level
					Level IV	Level IV	Level IV	Level IV	Level IV
	Level II 20/09/10	Level III 21/10/10	Level IV 25/10/10	Safe zone 10 km	Safe zone 15km	Safe zone 20 km	Update Safe zone	Update Safe zone	Level III 03/12/10	Level II 30/12/10
					26/10/10	04/11/10	05/11/10	14/11/10	19/11/10
											A	25 Oct -2 Nov	B	3-4
	The authorities have adapted the
	evacuation zones based on the
	evolution of volcanic activity:
	* Period A, 25 October-2
	November. According to the 2009
	hazard zone map, CVGHM
	recommended evacuation of 12
	municipalities located in KRB III
	(Purwobinangun,	Wonokerto,
	Girikerto, Umbulharjo,	Hargobinangun, Kepuharjo,						Boyong Riv er
	Glagaharjo, Balerante, Sidorejo,
	Tegalmulyo,	Kemiren	and
	Kaliurang).
	* Period B, 3-4 November. CVGHM
	recommended evacuation of 32
	municipalities in the KRB III, abandoning the 2009 map for the	C					D	E
	benefit of new evacuation plans
	updated according to the danger
	zone radius changes.
	* Period C, 5-13 November. Several
	hours before the paroxysmal
	eruption, CVGHM extended the
	restricted zone to 20 km from the
	summit	and	recommended
	evacuation of people in this radius.
	* Period D, 14-19 November.
	Radius of 20 km for the sector
	between the Boyong and Gendol
	rivers was maintained. The radius
	was reduced to 15 km for
	Magelang District and 10 km for
	Klaten District and Boyolali District.

  Source: data from Mei and Lavigne, 2012;Mei et al., 2013

	Beliefs and behaviours during the 2010 eruption
	Return home during evacuation period
		Before	After
			5%		Return home during
		32%			evacua on period
		68%	43%	52%	Did not return home period during evacua on
					Others: no answer
	Reasons to return home during evacuation
	Evacuation refusal
		Before	After
	8%	13%	13%	24%	Feed the ca le Worried of No longer afraid of erup on
	5%				Take belongings/property
		70%	59%		See condi on of house Take care of house
					Take a bath
	People's perception of volcanic eruption
		8%	God (religious reason)
		13%	34%	Nature (scien c reason)
		3% 8%		Socio-cultural reason Mixed God-Nature-Culture
				Others
			34%	No answer
	ru T st in government and volcanologists
		1%	4%
			23%	Strongly believe
				Believe
				Li le
				Do not believe
		72%		No answer

Return of pilgrims from Mecca Departure of pilgrims to Mecca Airport closed

																																								F.7
	Impacts of the eruption on air traffic
	Passengers per day in Yogyakarta and Surakarta Airports
		Airport
		Air link increase
		Air link decrease
		Bus transfer for pilgrims
		Railway
																																	Source: data from Picquout, 2013
	7°30'0"S Passengers per day in Yogyakarta and Surakarta Airports Selo
		Yogyakarta
	14,000
	12,000
	10,000
	8,000								Ngargomulyo
	6,000			Muntilan
	4,000													Kaliurang
	2,000
	0
	7,000
	6,000	Surakarta												International
	5,000						Sleman									Bronggang Domestic
	4,000																								7°40'0"S
	3,000
	2,000																Bimomartani
	1,000																				Refusal
																					No refusal
	0																				No answer
		1/10/10	3/10/10	5/10/10	7/10/10	9/10/10	110°20'0"E 0 11/10/10 13/10/10 15/10/10 17/10/10	2 19/10/10	21/10/10	4 Km 23/10/10 25/10/10	27/10/10	29/10/10	31/10/10	2/11/10	4/11/10	6/11/10	8/11/10	10/11/10	110°30'0"E 12/11/10 14/11/10 16/11/10 18/11/10	20/11/10	22/11/10	24/11/10	26/11/10	28/11/10	30/11/10	2/12/10	4/12/10	6/12/10	8/12/10	10/12/10	12/12/10	14/12/10	16/12/10	18/12/10	20/12/10	22/12/10	24/12/10	26/12/10	28/12/10	30/12/10

© ? ? ? ? ? ? ? ? 2010.

CMG-40T DOAS Camera at Jrakah DOAS Camera at Jrakah Pasar Bubar Station Seismic Antenna Station GPS Station at Pasa r Buba r Stereograph installation at Deles Multiparameter station at Lava 1902

  Merapi monitoring system combines a variety of methods of various disciplines: visual, geological, geophysical (seismic and deformation), and geochemical (gas analysis).

					H.3
	Pasar Bubar Station	Seismic Antenna Station	GPS Station at Pasa r Buba r	Stereograph	Multiparameter station at Lava 1902
				installation at Deles
	1 km	2 km

*: https://sites.google.com/site/domerapi2/

We thank the following persons who provided valuable advice or technical help for this atlas: Monique Gherardi, Emilie Lagahe, Frédéric Leone, Annabelle Moatty, Paul Valery University and GRED, Montpellier III-IRD, France Dr. Sri Hidayati, Center for Volcanology and Geological Hazard Mitigation, Bandung, Indonesia Ir Dewi Sri Sayudi, Ir. Moch Muzani, Ir Nurnaning Aisyah, Ir. Subandriyo, Balai Penyelidikan dan Pengembangan Teknologi Kebencanaan Geologi (BPPTKG), Yogyakarta, Indonesia Delphine Grancher, Daniel Brunstein, Claude Legentil, Céline Vidal, Laboratoire de Géographie Physique, UMR 8591, CNRS, Paris 1, UPEC, France Jeffe Castan, independant photographer Translation Acknowledgements Design contribution Contact Franck Lavigne franck.lavigne@lgp.cnrs.fr Julie Morin julieapi@yahoo.fr Edited by Pr. Franck Lavigne, Dr. Julie MORIN, Dr. Surono

Axa Research Fund are not liable for any use that may be made of the information contained therein.

WebObs: An integrated web-based system for observatories (2) GPS data automatic processing GPS stations record data at 1-Hz sampling and raw files are automatically transmitted to BPPTKG every hour. Precise positioning is performed using GIPSY-OASIS (JPL) software with the best available orbits precision and ITRF08 global referencing.

WebObs processing exports graphs at different time scales (2 months, 1 year, all data): time series, velocity vectors, and deformation source modeling from relative displacements inversion.

Seismic stripchart and bulletin

A digital stripchart is included in WebObs (SEFRAN): it uses Seedlink/Arclink data streams to produce multi-stations seismograms in real-time.

Manual picking and event identification allows to fill and edit a simple seismic bulletin with graph, search and filter facilities.

Access to original waveforms is made through miniseed files. Requests can also be made by web-service (a simple URL chain).

Combined with a SeisComP3 database and QuakeML export, it provides dynamic access to location and magnitude information of events, and also automatic triggering possibilities.

H.5

Source Authors and Credits