{"id":211413,"date":"2022-08-01T20:51:28","date_gmt":"2022-08-01T18:51:28","guid":{"rendered":"https:\/\/climatescience.press\/?p=211413"},"modified":"2022-08-01T20:51:29","modified_gmt":"2022-08-01T18:51:29","slug":"the-sahara-is-green-when-warm-desert-when-coldand-its-drier-now-than-the-last-glacial-maximum","status":"publish","type":"post","link":"https:\/\/climatescience.press\/?p=211413","title":{"rendered":"The Sahara Is Green When Warm, Desert When Cold\u2026And It\u2019s Drier Now Than the Last Glacial Maximum."},"content":{"rendered":"\n

If wetter is warmer and drier is colder, the modern Saharan climate suggests we are not in a warm period.<\/strong><\/h4>\n\n\n\n

<\/p>\n\n\n\n

It is common knowledge that warmer temperatures are associated with wetter, greener climates, and cooler temperatures are linked to droughts, browning, crop failures, etc.<\/p>\n\n\n\n

For example, in the continental US there is a \u201crobust association between pan-CONUS drought events and cold tropical Pacific conditions\u201d (Baek et al., 2019<\/a><\/strong>). Again, cooling sea surface temperatures are the \u201cprincipal driver\u201d of drought across the US.<\/p>\n\n\n\n

<\/p>\n\n\n

\n
\"\"<\/figure>\n<\/div>\n\n\n
Image Source:\u00a0Baek et al., 2019<\/a><\/strong><\/h6>\n\n\n\n

<\/p>\n\n\n\n

During the Green Sahara period or African Humid Period which spanned from 14,500 to 5,000 years ago (peaking from 11 to 6 thousand years ago), a much warmer northern Africa was teeming with lakes, fish, grasslands, megafauna, trees, and human civilizations.<\/p>\n\n\n

\n
\"\"<\/figure>\n<\/div>\n\n\n
Image Source:\u00a0LiveScience<\/a><\/strong><\/h6>\n\n\n\n

<\/p>\n\n\n\n

About 5,000 years ago the regional Saharan climate steadily cooled, and this post-Mid Holocene cooling is significantly linked to the habitat-destroying desert conditions that exist in Northern Africa today.<\/p>\n\n\n\n

According to a 2021 study<\/a><\/strong> published in PNAS<\/em>, today\u2019s temperatures in the Saharan region are the coldest of the last 13,500 years with the exception of a few centuries centered around 4,000 years ago.<\/p>\n\n\n\n

And, correspondingly, the aridity in this region is worse today than anytime in the last 18,500 years, or since the peak of the last glacial, when CO2 was under 200 ppm.<\/p>\n\n\n\n

Hyper-aridity in the modern regional climate is not consistent with claims we are now experiencing a period of exceptional warmth. The opposite, actually.<\/p>\n\n\n

\n
\"\"<\/figure>\n<\/div>\n\n\n
Image Source:\u00a0Cheddadi et al., 2021<\/a><\/strong><\/h6>\n\n\n\n

<\/p>\n\n\n

\n
\"\"<\/figure>\n<\/div>\n\n\n
Image Source:\u00a0Ramos-Rom\u00e1n et al., 2018<\/a><\/strong><\/h6>\n\n\n\n

<\/p>\n\n\n\n

<\/p>\n\n\n\n

via NoTricksZone<\/mark><\/em><\/strong><\/p>\n\n\n\n

By\u00a0Kenneth Richard<\/a>\u00a0on\u00a0<\/em>1. August 2022<\/p>\n\n\n\n

\n
The Sahara Is Green When Warm, Desert When Cold…And It’s Drier Now Than The Last Glacial Maximum.<\/a><\/blockquote>