The Landslide Blog is written by Dave Petley, who is widely recognized as a world leader in the study and management of landslides.
The trend of high rates of occurrence for global fatal landslides in 2024 has continued through July. My provisional data for July 2024 has 95 events occurring worldwide in July, with 1,167 fatalities. In terms of numbers of events, this makes July 2024 the second worst on record (after July 2019, in which I recorded 98 events). As usual, this data does not include events triggered by earthquakes.
The net effect is that 2024 continues to be exceptional in terms of fatal landslides. This is the graph of cumulative events by month, with 2024 in black and previous years in grey:-
As the graph shows, 2024 is an outlier to a remarkable degree (more than three standard deviations above the mean), and indeed the total to the end of July has already exceeded the annual total (i.e. the cumulative total at the end of December) for all but six years of my records.
In terms of fatalities, the month was dominated by two major events. The 30 July 2024 debris flow at Wayanad in Kerala in India has left about 560 people dead or missing, although the recovery operations continue at the site. In fatality terms, this is the worst event of the year so far. But the 21/22 July 2024 landslide at Gofa Zone in Ethiopia also inflicted a horrifically high toll, with 257 fatalities.
Elsewhere there have been many events across South Asia, most notably in northern India, Bangladesh and Nepal. In India, the 2024 SW Monsoon is running considerably above the long term average in terms of total rainfall, which explains the high landslide incidence in this region.
China, the Philippines and Vietnam have also been hit hard, whilst Kyrgyzstan is suffering a record number of mudflows.
At this stage, I can only speculate on the likely underlying reasons for this very high incidence of fatal landslides. The most likely cause continues to be the exceptionally high global surface temperatures, and the resultant increase in high intensity rainfall events. These high temperatures are associated with the combination of long term anthropogenic warming and the recent El Nino. The latter is now fading away – indeed we are now in El Nino neutral conditions – but global surface temperature has remained high. It will be interesting to see what happens in the coming months.
In general, August has a lower number of global fatal landslides than July (the long term average is 60 events for July and 53 events for August), mainly because (on average) the SW monsoon in South Asia starts to weaken from the middle of July. However, intense rainfall events can still occur through August and September in this region.
Another significant threat will be tropical cyclones in the North Atlantic and the West Pacific. For example, keep a close eye on Tropical Storm Ampil, which could make landfall in Japan in the coming days.
Explaining the data
The research that underpins this post is explained in Froude and Petley (2018), which is open access, and in Petley (2012). References below.
Froude, M. and Petley, D.N. 2018. Global fatal landslide occurrence from 2004 to 2016. Natural Hazards and Earth System Sciences 18, 2161-2181.
Petley, D.N. 2012. Global patterns of loss of life from landslides. Geology 40 (10), 927-930.
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