Dr. Stefan Kröpelin, who specializes in the study of the eastern Sahara Desert and its climatic history, has been active in the field over there for more than 40 years. He said in a recent interview that deserts like the Sahara are actually shrinking, meaning they are becoming greener with plants and vegetation.

Going back as far as the late 1980s, rains have been spreading across northern Sudan and elsewhere in northern Africa. This has had the effect of greening the region and making the harsh Sahara Desert smaller than it once was.

"The desert is shrinking," Dr. Kröpelin said in the interview. "It is not growing."

(Related: Earlier this year, PBS announced the unveiling of a new "climate psychology therapist" to help mentally ill climate fanatics cope with the reality of carbon.)