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“Nobody lives in the global average”

Last week it was Donegal, this week it's Houston (see also the Mann article linked below), in the weeks prior it was Vietnam, India, and numerous other places.

Heavy rainfall and flooding were also identified by the photovoice participants in My Loi as their primary worry in relation to climate-related risks:

Watermarks on the wall in this house are a reminder of the previous year's floods.

 

Is the seemingly endless news of 'catastrophic' flooding events the result of a hyper-vigilant and ubiquitous media presence or is there a real climate-related trend? Studies have shown that as the planet warms, rates of evaporation will increase, and the air will hold more moisture, leading to what sound like manageable increases in precipitation. No more than with temperature however, averages can be deceptive (for example, the Arctic is warming at a much faster rate than the global average). As remarked in a 2016 article in Nature Climate Change 'Global average precipitation is expected to increase moderately with global warming, but nobody lives in the global average.'

Future trends?

While there is considerable uncertainty, particularly in relation to spatial variability, it looks like the future holds further increases in extreme rainfall events in both wet and dry regions, even while the overall trend may be towards a 'wet gets wetter, dry gets drier' scenario (Collins, M. et al. in Climate Change 2013: The Physical Science Basis (eds Stocker, T. F. et al.) 10291136 (IPCC, Cambridge Univ. Press, 2013) quoted in https://www.nature.com/nclimate/journal/v6/n5/full/nclimate2966.html#ref2).

See:

Donat, M. G., Lowry, A. L., Alexander, L. V., Ogorman, P. A., & Maher, N. (2016). More extreme precipitation in the world[rsquor]s dry and wet regions [Letter]. Nature Clim. Change, 6(5), 508-513. doi:10.1038/nclimate2941

Ingram, W. (2016). Extreme precipitation: Increases all round [News and Views]. Nature Clim. Change, 6(5), 443-444. doi:10.1038/nclimate2966

Michael Mann on the climate change impact on the Houston floods