5 February 2011

Global deaths from landslides in 2010 (updated to include a comparison with previous years)

Posted by Dave Petley

NB: I have updated this post this morning to include some data on losses from previous years.

I have finally managed to process the 2010 data in my database on lives lost from landslides around the world.  This post presents a summary of the findings.

First, the overall picture.  In total I recorded 6,211 deaths in 494 landslide events.  This is lower than in some previous years because of the lack of large-scale, landslide-triggering earthquakes.  However, in terms of rainfall-induced events this was a bad year.  This is illustrated by the two graphs below.  On the left is the total fatalities that I have recorded from 2003 to 2010, including losses from landslides triggered by earthquakes.  On the right is the same data but with the two huge landslide-inducing earthquakes (2005 Kashmir and 2008 Wenchuan) removed:

In total I have recorded 83,275 deaths from landslides since September 2002, a devastating total.  It is also interesting to note that my data continue to record an increasing trend in the number of non-seismically induced landslides that kill people.  Whilst an element of this may be associated with improved data, my interpretation is that this does reflect a real increase in the number of landslides occurring worldwide.  This is clearly a worrying trend:

The largest event in terms of lives lost was the Zhouqu landslide in China on 8th August (pictured to the right), which killed 1765 people.  Other very large events were the 2nd March Bududa landslide (358 deaths); the 6th April Morrao de Bubma landslide in Niteroi, Brazil (196 deaths); the 7th August debris flows in Leh, India (234 deaths); and the 4th October Wasior landslide in West Papua, Indonesia (145 deaths).

The global data that I collect typically shows a peak in the northern hemisphere summer (July and August) and a minimum in December.  This year was no exception, as the graph, which plots the number of recorded landslides that killed one or more people, through the year in pentads (five day blocks):

In terms of geographic distribution, the two pie charts below show the continents with the greatest impacts.  The chart on the left shows the number of  landslides, whilst the one on the right shows the fatalities.  As usual Asia dominates.  This year the number of events and deaths was greatest in East Asia; in some years this is in South Asia.

Naturally the dominance of E. Asia this year reflects the very serious landslide problems in China. Unsurprisingly then China was the most seriously impacted nation:

This chart shows, using the bars and the left axis, the number of deaths for the 15 nations with the largest impacts, in rank order from left to right.  The line graph shows the number of fatality-inducing landslides recorded in each country (right axis).

Unfortunately, the heavy rains in Brazil, Sri Lanka and the Philippines mean that 2011 has started badly as well.

Comments, thoughts and corrections welcome.