The Landslide Blog is written by Dave Petley, who is widely recognized as a world leader in the study and management of landslides.
The extraordinary landslide year of 2024 is now complete, so I’m able to provide my initial analysis of the fatal events that have occurred. Remember that this is an analysis only of fatal events- there have been literally hundreds of thousands of non-fatal landslides too, but at present we have no mechanism to collate these reliably.
I will seek to publish this data in a journal in the coming months, so the analysis presented here is provisional.
The methodology and background analysis is outlined in Froude and Petley (2018), which is an open access paper. There are also reflections on these analyses in Fidan et al. (2024), which is also open access.
As I have been describing through the year, 2024 was exceptional in every way in terms of fatal landslides. In total, I recorded 708 fatal landslides (excluding those triggered by an earthquake), costing 4,492 lives. In terms of the number of fatal landslides, this is the highest annual total that I have ever recorded, breaking the previous record by over 100 events.
The map below shows the distribution of these fatal landslides, with each of the dots representing a single fatal event:-
The distribution is in line with previous years, although there is an increasing concentration in central Africa.
In terms of occurrence through the year, the graph below shows this data, organised by pentad (five day blocks):-
As usual I have included two typical previous years (2018 and 2019) to illustrate how exceptional 2024 has been. The year was reasonably typical until about day 55 (towards the end of February), but from that point onwards the rate at which fatal landslides occurred has been above the norm.
In addition, the typical acceleration in rate that is associated with the northern hemisphere summer (driven by monsoon rainfall in Asia) started much earlier than is normal (around day 120 rather than day 180). The big step in the autumn is the impact of the terrible late monsoon (26-28 September 2024) rainfall event in Nepal. But even without that event, 2024 was remarkable.
To put this into context, the graph below shows the cumulative total number of fatal landslides (in black) with previous years (in grey):-
So why have we seen this anomalous pattern? At this stage I can only speculate – much more rigorous analysis is needed. But I doubt that it is a coincidence that 2024 has seen exceptional global atmospheric and sea surface temperatures, and as a consequence there have been very high peak rainfall intensities. Slopes are sensitive to rainfall intensities in general, and fatal landslides specifically are often associated with shallow landslides that transition into channelised debris flows, which are often triggered by very intense rainfall.
So now I start again with the collection of data for 2025. Will the totals be as high? My prediction, for what it is worth, is that they will not, reflecting a slightly cooler year. But time will tell. As always, I will endeavour to provide monthly updates via this blog.
And finally, many thanks to all those who have helped to identify events. The collation of this data is a community effort – your help is invaluable. And thanks in advance to those who will highlight events to me in 2025 – I value every single contribution.
References
Froude M.J. and Petley D.N. 2018. Global fatal landslide occurrence from 2004 to 2016. Natural Hazards and Earth System Science 18, 2161-2181. https://doi.org/10.5194/nhess-18-2161-2018
Fidan, S., Tanyaş, H., Akbaş, A. et al. 2024. Understanding fatal landslides at global scales: a summary of topographic, climatic, and anthropogenic perspectives. Natural Hazards (2024). https://doi.org/10.1007/s11069-024-06487-3
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