May 12 — the third anniversary of the devastating earthquake Venchuanskogo, also known as Sichuan. In honor of this sad date of Chengdu University of Technology organized a conference on the problem of landslides induced by earthquakes. My presentation will be held in the morning session and the focus there will be deaths from landslides caused by earthquakes. I will also mention our journal Nature Geoscience, coming Sunday, in the discussion regarding the balance of mass in the range. I also write about this interesting issue in the blog.
Question death is also mentioned in PDF-document dosupnom this link: 11_05 China keynote Petley blog
Below I will try to describe the key aspects of the performance.
Regular readers know that one of the aspects of my research is to collect data on landslides, which killed people. I did that in September 2002, and periodically publish in this blog. In the presentation of the data evaluated with emphasis on seismic landslides. During the period from September 1, 2002 to December 31, 2010 I have recorded nearly 82,000 killed in landslides.
Information is reflected in the graph:
It can be seen that the dominant growth deaths associated with two earthquakes — in Kashmir in 2005 and Wenchuan in 2008. Unfortunately, the exact figure on the Kashmir earthquake spread. Approximately one can establish that by landslides killed 26,400 people there. As a result of the same processes in Venchuanskom earthquake killed 20,000.
Interestingly, the increase in the number of deaths from landslides caused by rains, is almost linearly:
Joint schedule seismic landslides reveals two burst from the big disasters, but in fact in this period happened 32 earthquake that caused fatal landslides:
This implies that more than 50% of those killed by landslides over the period studied, died in landslides caused by the earthquake.
Specifically, it shows the importance of the fact that we need to better understand yavlyaeniya provoked by earthquakes.
Data collected by me (black dots) can be combined with information obtained from the literature (white dots) to get an initial assessment of the number of deaths due to landslides with magnitude earthquake. Scatter of values is large, but we can define two threshold levels. Orange line indicates the limit for 90% of the events, and the red line restricts all events have occurred:
This is only a preliminary analysis that requires further work.
Finally, the greatest increase in deaths from landslides observed in the aftermath of earthquakes, which is understandable. View data for the Sichuan earthquake before and after, I noticed a significant increase in deaths caused by landslides after the disaster:
As can be seen, after the earthquake occurred the death of 300 more people in a shorter period. Interestingly, there has been a marked increase in the number of serious landslides, but only increase the number of deaths for each landslide. This may mean that I can not register the weaker landslides in the aftermath of the earthquake:
All of this information is intended to show that the data do not allow to assess the real impact of landslides.
The actual loss is undoubtedly much higher, but I must stress that the serious earthquake victims counting accuracy is not high.