IPCC Special Report - Latest Findings on Extreme Weather Events

The report suggests that droughts will intensify during the 21st century

Working Groups I and II for the IPCC have produced a special report for 'Managing the Risks of Extreme Events and Disasters to Advance Climate Change Adaptation' (SREX for short). The findings of the Special Report were presented at the IPCC's 34th session, which is currently being held in Kampala, Uganda. The full report is not available until February 2012, but a 29 page summary has been made available and can be downloaded here.

I've listed some of the key findings below, but I would urge you to take a look at the full report yourselves:

> "A changing climate leads to changes in the frequency, intensity, spatial extent, duration, and timing of extreme weather and climate events, and can result in unprecedented extreme weather and climate events."

> There is evidence that some extremes have changed as a result of anthropogenic influences, including increases in atmospheric concentrations of greenhouse gases. It is likely that anthropogenic influences have led to warming of extreme daily minimum and maximum temperatures on the global scale.

> "It is likely that the frequency of heavy precipitation or the proportion of total rainfall from heavy falls will increase in the 21st century over many areas of the globe."

> "Average tropical cyclone maximum wind speed is likely to increase, although increases may not occur in all ocean basins. It is likely that the global frequency of tropical cyclones will either decrease or remain essentially unchanged."

> "There is medium confidence that droughts will intensify in the 21st century in some seasons and areas, due to reduced precipitation and/or increased evapotranspiration."

> There is high confidence that changes in heat waves, glacial retreat and/or permafrost degradation will affect high mountain phenomena such as slope instabilities, movements of mass, and glacial lake outburst floods.

The summary is very cautious with it's findings and confidence levels, stating that "Extreme events are rare, which means there are few data available to make assessments regarding changes in their frequency or intensity." As has been discussed in previous posts and seen in the current academic literature, it becomes very difficult to isolate a single event, like a heatwave or a heavy rainstorm, and say that event was caused by the human element of climate change.

Despite this, the report is yet another contribution to the scientific community suggesting that anthropogenic impacts are having a direct impact on extreme weather events.