How did ocean warming affect Australian rainfall extremes during the 2010/2011 La Niña event?
Ummenhofer, Caroline C.
Sen Gupta, Alexander
England, Matthew H.
Taschetto, Andrea S.
Briggs, Peter R.
Raupach, Michael R.
MetadataShow full item record
Extreme rainfall conditions in Australia during the 2010/2011 La Niña resulted in devastating floods claiming 35 lives, causing billions of dollars in damages, and far-reaching impacts on global climate, including a significant drop in global sea level and record terrestrial carbon uptake. Northeast Australian 2010/2011 rainfall was 84% above average, unusual even for a strong La Niña, and soil moisture conditions were unprecedented since 1950. Here we demonstrate that the warmer background state increased the likelihood of the extreme rainfall response. Using atmospheric general circulation model experiments with 2010/2011 ocean conditions with and without long-term warming, we identify the mechanisms that increase the likelihood of extreme rainfall: additional ocean warming enhanced onshore moisture transport onto Australia and ascent and precipitation over the northeast. Our results highlight the role of long-term ocean warming for modifying rain-producing atmospheric circulation conditions, increasing the likelihood of extreme precipitation for Australia during future La Niña events.
Author Posting. © American Geophysical Union, 2015. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Geophysical Research Letters 42 (2015): 9942–9951, doi:10.1002/2015GL065948.
Showing items related by title, author, creator and subject.
The role of atmospheric forcing versus ocean advection during the extreme warming of the Northeast U.S. continental shelf in 2012 Chen, Ke; Gawarkiewicz, Glen G.; Kwon, Young-Oh; Zhang, Weifeng G. (John Wiley & Sons, 2015-06-15)In the coastal ocean off the Northeast U.S., the sea surface temperature (SST) in the first half of 2012 was the highest on the record for the past roughly 150 years of recorded observations. The underlying dynamical ...
Thorrold, Simon R.; Afonso, Pedro; Fontes, Jorge; Braun, Camrin D.; Santos, Ricardo S.; Skomal, Gregory B.; Berumen, Michael L. (Nature Publishing Group, 2014-07-01)Ecological connections between surface waters and the deep ocean remain poorly studied despite the high biomass of fishes and squids residing at depths beyond the euphotic zone. These animals likely support pelagic food ...
Extreme rainfall activity in the Australian tropics reflects changes in the El Niño/Southern Oscillation over the last two millennia Denniston, Rhawn F.; Villarini, Gabriele; Gonzales, Angelique N.; Wyrwoll, Karl-Heinz; Polyak, Victor J.; Ummenhofer, Caroline C.; Lachniet, Matthew S.; Wanamaker, Alan D.; Humphreys, William F.; Woods, David; Cugley, John (2015-03)Assessing temporal variability in extreme rainfall events prior to the historical era is complicated by the sparsity of long-term ‘direct’ storm proxies. Here we present a 2200-yr-long, accurate and precisely dated record ...