Nature Climate Change (2012, v2, pp775-779) / by Clara Deser, Reto Knutti, Susan Solomon and Adam S. Phillips
[Real Climate] A new paper by Deser et al. (2012) (free access) is likely to have repercussions on discussions of local climate change adaptation. I think it caught some people by surprise, even if the results perhaps should not be so surprising. The range of possible local and regional climate outcomes may turn out to be larger than expected for regions such as North America and Europe.
Deser et al. imply that information about the future regional climate is more blurred than previously anticipated because of large-scale atmospheric flow responsible for variations in regional climates. They found that regional temperatures and precipitation for the next 50 years may be less predictable due to the chaotic nature of the large-scale atmospheric flow. This has implications for climate change downscaling and climate change adaptation, and suggests a need to anticipate a wider range of situations in climate risk analyses.
Although it has long been recognised that large-scale circulation regimes affect seasonal, inter-annual climate, and decadal variations, the expectations have been that anthropogenic climate changes will dominate on time scales longer than 50 years…It has long been recognized that local and regional climate would warm at different rates than the global mean, but not with such large differences as presented by Deser et al. at the time scales of 50 years and for continental scales. Their results imply that while some regions could experience almost zero warming over 50 years, this will be compensated by substantially stronger in other regions…