In some places, 2010 was the hottest year on record. Saudi Arabia – with its enormous swath of desert – was particularly hard hit, while Egypt stewed during a series of blackouts amidst brain-pickling heat. The discomfort of those painful summer months may have dissipated as temperatures begin to dip, but prepare yourself: in the next few decades, particularly around the Mediterranean, our brains could shrivel to nothing under heat and drought that our planet may never have experienced before.
Similar to the Richter scale that measures the severity of earthquakes, the Palmer Drought Severity Index (PDSI) rates droughts. Negative numbers refer to dry conditions and positive numbers refer to wetter conditions. Though many northern latitudes will get wetter as warm air holds more moisture, dry southern and subtropical areas are likely to become so hot and so dry that the PDSI will no longer be relevant.
This news was reported by the University Corporation for Atmospheric Research (UCAR), and relies on data published by Alguo Dai, a scientist for the National Center for Atmospheric Research.
“Using an ensemble of 22 computer climate models and a comprehensive index of drought conditions, as well as analyses of previously published studies, the paper finds most of the Western Hemisphere, along with large parts of Eurasia, Africa, and Australia, may be at threat of extreme drought this century,” according to UCAR.
Based on current projections of greenhouse gas emissions and natural climate cycles but subject to variability (cross your fingers we can bring down carbon emissions) these models estimate the possibilities. And the possibilities are alarming, to say the least.
According to the study, numerous regions, including the Southwest United States, Latin America, Africa, Australia, and SW and SE Asia, will experience rougher droughts, but countries bordering the Mediterranean Sea will become “especially dry.”
A climate change expert not associated with the study, Richard Seager of Columbia University’s Lamont Doherty Earth Observatory said to UCAR:
“…vast swaths of the subtropics and the midlatitude continents face a future with drier soils and less surface water as a result of reducing rainfall and increasing evaporation driven by a warming atmosphere. The term ‘global warming’ does not do justice to the climatic changes the world will experience in coming decades. Some of the worst disruptions we face will involve water, not just temperature.”
Twenty-two countries border the Mediterranean. Among them are Israel, Turkey, Egypt, Lebanon, and Syria, for example, all of which already battle with hot and dry summers and attendant water shortages. The hotter it gets in dry regions, the less rain will fall, which means less soil moisture and fewer agricultural yields in turn.
Up until now, it is rare to find droughts that fall under -6 on the Palmer scale, but this series of maps demonstrates that by the close of the century, the Mediterranean is likely to experience drought conditions that rate -15 to -20.
Failure to produce meaningful change in our carbon-choked social structure could literally burn us.
More on drought and high temperatures throughout the Middle East: