A couple hugs while standing on a hilly area overlooking Cairo on a dusty and hazy day where temperatures reached 114 Fahrenheit, May 27, 2015. REUTERS/Asmaa Waguih
Small forest fires are pictured between pine trees at night at Sierra de Tejeda nature park in southern Spain early June 30, 2014. REUTERS/Jon Nazca
Bjorn Lomborg, author of "The Skeptical Environmentalist," used to argue that concern about climate change was overblown because there were better causes to spend money on such as curing AIDS or malaria.