International: Embedding analysis of seismic hazard and risk for improved welfare in Bishkek, Kyrgyzstan

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The country of Kyrgyzstan in Central Asia is exposed to the hazards of earthquakes. The tectonic collision of the Earth's plates is creating huge mountains in this region. These mountains are created from earthquakes on large faults along the northern Tien Shan mountain range. Kyrgyzstan's' capital, Bishkek, lies on top of one of these major fault lines and is home to a million people. In the past, major cities that exist along the northern edge of this mountain range, such as Almaty to the east, have been destroyed in large earthquakes at the end of the 19th Century. This occurred when they were relatively small towns. The impact today from similar sized earthquakes would have a much more devastating effect if it were to strike the major city of Bishkek. The rapid expansion of cities in poorer countries has meant that a large number of buildings are not strong enough to be resilient to earthquakes.We want to help the Government ministries in Bishkek, such as the Ministry for Construction and also for Emergency Situations, to be able to better assess the potential impact for earthquakes to strike the city in future. We will do this by providing them with estimates of how many people may die in future earthquakes, how many buildings will be damaged or collapse, and how much such an earthquake will cost financially. We will also provide maps of where we think the city will be most affected by different types of earthquakes, as small nearby earthquakes can have as big an impact as distant large ones. This will enable the Kyrgyz government ministries to target where in the city key buildings, such as schools and hospitals, should be reinforced, as well as to better plan where new housing estates should be built, and also to enforce the seismic building codes to make sure the buildings are built better.In order to provide this latest information, we will be working with the Institute of Seismology in Bishkek, whose responsibility it is to provide these kinds of estimates of seismic risk. We are therefore working directly with the organisation that has the mandate to provide information to the government and by doing so we will ensure that our work will also have an impact. We are also going to train the institute staff to be able to update these estimates of losses so that they have the capacity to continue this work once we are no longer working on this project.It is important to be able to keep updating the estimates of losses and maps of seismic risk. Cities are constantly enlarging. If these cities lie in earthquake prone areas, such as the Kyrgyz capital of Bishkek, this growth increases their exposure to seismic hazards, increasing the risk that people face. Often some of the best views over a city come from higher ground, but this high ground is created by faults that build mountains. The city of Bishkek is expanding southwards as the urban population grows, and homes are now being built right on top of these fault lines. Being very near to a fault increases the amount of shaking if an earthquake happens, and therefore increases the chances of the building collapsing, injuring or killing the occupants.As well as the increased exposure to earthquake hazards, we are also discovering more active faults in the region through mapping out the fault lines and identifying past earthquake ruptures. It is important to incorporate this new information into the estimates of seismic hazard, as some very large earthquakes are known to have struck the region in the past. Therefore we will include this recent scientific information into our estimates of seismic hazard.We are working with other partners, such as the Global Earthquake Model Foundation, which was created to serve the public good through collaboration, openness and transparency by providing credible assessments of seismic hazard and risk. Their open software "OpenQuake" enables us to do the calculations of seismic risk.