The 2009 fatal landslide map and statistics

This post presents the data from the Durham University Fatal Landslide database for 2009. First, this is the map of fatal landslides. Each red dot represents a single landslide recorded on the database. Click on the map for a better view in a new window:


The map shows the usual distribution. Note the high incidence of landslides in SW India, the Philippines and in java in Indonesia. The high occurrence of landslides along the southern margin of the Himalayan mountain chain is also clear, but is less continuous than usual. This reflects the 2009 monsoon rainfall pattern, which was substantially below average, especially in the northwest of India, as the map below (for India only), from Monsoon Online, shows. The map indicates the departure from the mean annual monsoon rainfall:

In terms of statistics, the key data are:

• Number of recorded fatal landslides: 493 (this is substantially above the long term average).
• Number of recorded fatalities: 3611 (this is substantially below the long term average, primarily because there were no large earthquakes in populated mountainous areas).

Munich Re's list of the largest disasters of 2009

The reinsurance giant Munich Re releases annual statistics on the losses from natural catastrophes each year. They released the data for 2009 yesterday, presumably banking on the balance of probabilities that there would be no more major events in the three days left of the year. The release is available here:

http://www.munichre.com/en/press/press_releases/2009/2009_12_29_press_release.aspx

Overall results
The news for 2009 is good, with no disasters causing mass (i.e. >10,000) fatalities. There list of the top ten events in terms of fatalities is as follows (NB using the logical European style date format of dd.mm.yyyy):

• 30.09/1.10.2009: Indonesia: Earthquakes, 1,195 deaths
• 26-30.09.2009: South East Asia, East Asia: Typhoon Ketsana, 694 deaths
• 07-10.08.2009: China, Philippines, Taiwan: Typhoon Morakot, 614 deaths
• 03-14.10.2009: South East Asia, East Asia: Typhoon Parma, 469 deaths
• 25-27.05.2009: Bangladesh, Bhutan, India: Cyclone Aila, 320 deaths
• 29.09.-15.10.2009: India: Floods, 300 deaths
• 06.04.2009: Italy: Earthquakes, 295 deaths
• 21.08-15.09.2009: India: Floods, 223 deaths
• Aug-Sep 2009: West Africa, Central Africa: Floods, 215 deaths
• 04-13.11.2009 El Salvador, Nicaragua, Mexico, USA: Hurricane Ida, 204 deaths

Two aspects of these statistics are particularly interesting. First, the lack of a really large event is pleasing, but is probably no more than a serendipitous lack of a large earthquake in a populated area and limited numbers of large land-falling tropical cyclones, especially in the Atlantic basin. Second, the top five events were all associated with large numbers of landslide fatalities, most notably perhaps typhoon Morakot in Taiwan, the landslides triggered by the Indonesian earthquake and the multiple slides in the Philippines caused by typhoon Parma.

Geographical distribution
The geographical spread of these larger events is quite wide, including SE Asia, E. Asia, S. Asia, Africa, Europe and Central America. However, probably the most interesting aspect of this entire release is a map of showing the location of all the natural catastrophes that have occurred through the year:

There are several things to note here. First, you may well have spotted that the highest density of catastrophes appears to have occurred in the United States, Europe and China. This of course reflects the vulnerability of countries with large asset values to geophysical and meteorological processes. Second, the distribution of the event types is quite varied. The climatological events are mostly concentrated in the USA and Australia; Europe and N. America is mostly affected by storms, whilst in Asia the events are primarily floods. Africa probably has far fewer catastrophes than most people would expect.

Economic Losses
Economic losses were also lower than in previous years at $50 billion, compared with $200 billion in 2008. The largest loss-inducing event was a winter storm that affected N. Spain and France in late January, inducing losses of $5.1 billion. The USA was affected by four of the ten events that caused the highest costs in terms of losses.

Climate Change
The effects of climate change on disaster losses is very complex issue. I am increasingly persuaded by the argument that there is now a strong climate change signal in the loss data, primarily due to increased precipitation intensities and increased intensities of the largest tropical cyclones, both of which are supported by strong scientific evidence that has been subjected to peer review. Interestingly, Munich Re are also pretty clear on this point:

'Torsten Jeworrek, Munich Re Board member responsible for global reinsurance business, drew attention to the marked increase in major weather-related natural catastrophes worldwide since 1950, the number now having more or less tripled. Economic losses from weather-related natural catastrophes in the period since 1980 totalled approximately US$ 1,600 bn (in original values). "Climate change probably already accounts for a significant share. In the light of these facts, it is very disappointing that no breakthrough was achieved at the Copenhagen climate summit in December 2009. At Munich Re, we look closely at a multitude of risks and how best to handle them. Risks that change in the course of time are especially hazardous. Climate change is just such a risk of change."

Losses caused by climate change will continue to increase in the future. Jeworrek: "We need as soon as possible an agreement that significantly reduces greenhouse gas emissions because the climate reacts slowly and what we fail to do now will have a bearing for decades to come."'

In the next few days I will review landslide events both for 2009 and for the "noughties", and also the major, game-changing disasters of the last decade.

June 2008 fatal landslide map

The map below shows the distribution of fatal landslides for June 2008. The statistics are:
Number of fatal landslides: 43
Number of fatalities: 215

As has been the pattern all year, June was substantially below the average number of fatalities for may in 2003-2007, which is 334 deaths. Interestingly, during June there have been extensive reports of intense and prolonged rainfall events, but this does not seem to have translated into fatal landslides. The reasons for this are unclear to me.

June 2008 fatal landslide locations (click for a larger version)

The patterns that were starting to emerge in the annual map over the last few months are now clear. In particular the clusters in the Himalayas, western Central America, the Philippines and Indonesia are now very obvious. Whereas last month the cluster in the Himalayas was focused on the western part of the mountain chain, it has now extended to the east as the monsoon rainfall has intensified. The pattern of more landslides in Central America than is normal is continuing. China is continuing to get a fair number of fatal landslides. It is also interesting to see the occurrence of several landslides in SE. Europe.

Recorded fatal landslides in 2008 up to the end of June. Each dot represents a single landslide. Click on the map for a larger version in a new window.

May 2008 Landslide map

The map below shows the distribution of fatal landslides for May 2008. At the moment I am not including the landslides associated with the Sichuan earthquake as I cannot yet estimate the impacts of them. Clearly the numbers of landslides and the numbers of fatalities will dwarf the numbers below. I will try to ascertain the magnitudes in due course, though this is very challenging. I have included reported rainfall-triggered landslides in the aftermath of the earthquake, though again this is likely to be an underestimate.

The statistics are:
Number of fatal landslides (excluding those triggered by the Sichuan earthquake): 21
Number of fatalities: 280

May was once again very substantially below the average number of fatalities for may in 2003-2007, which is 336 deaths . In my post on the April figures I said that May "could be an interesting month!" I was right, but for the wrong reasons. The distribution is again fairly well-scattered, but as we come into the wet season it is increasingly focussed on Asia. The red triangle represents Sichuan.

May 2008 fatal landslide locations (click for a larger version)

The patterns that were starting to emerge in the annual map last month are now strengthening. In particular the inevitable clusters in the Himalayas, western Central America, the Philippines and Indonesia are now clear. The cluster in the Himalayas is still focused on the west side at the moment as this area gets heavy rain in the early part of the year. The monsoon rains have now started in the very southern part of the Indian subcontinent and will now start moving northwards. This will drive the growth of this cluster. There are certainly more landslides in Central America than is normal.

2008 fatal landslide locations to the end of May (click for a larger version)

So what of the month ahead? We, expect to see the number of fatal landslides increase markedly, especially in Asia. As the rains start in Central China landslides seem inevitable. As the La Nina conditions fade, we might expect to see fewer landslides in South America, but more in Asia.

April 2008 landslide map

The map below shows the distribution of fatal landslides for April 2008.

The statistics are:
Number of fatal landslides: 12
Number of fatalities: 33

As I predicted in March, April was once again very substantially below the average for 2003-2007, which is 96 fatalities per year. The distribution is very random, with absolutely no clear pattern. Two fatal landslides occurred in the Himalayan Arc, which is a sign of things to come over the next few months. La Nina conditions do still prevail, but the event continues to weaken. Typically the number of landslides starts to increase around early May. This is shown by the cumulative totals - for example, at the end of April 2004 I had recorded just 339 fatalities for the year to date (this years total is even lower - 301), but by the end of May 2004 this had jumped to 1136. It could be an interesting month!

April 2008 fatal landslide locations (click for a larger version)

Some patterns are starting to emerge in the annual map. Note in particular the emerging clusters in the Himalayas, western Central America, the Philippines and Indonesia. These are the normal locations for fatal landslide clusters. The cluster in the Himalayas is focused on the west side at the moment as this area gets heavy rain in the early part of the year. It will spread eastwards over the next three months.

2008 fatal landslide locations up to the end of April (click for a larger version)