A new study by scientists at the State Key Laboratory of Tropical Oceanography, in China, and published in the journal Geophysical Research Letters, predicts that if emissions of greenhouse gases go unchecked, summers in the Northern Hemisphere could last nearly six months by 2100. The impacts will be felt on human health, agriculture and ecology, such as the timing of animal feeding, breeding and migration, as well as promoting more heat waves, droughts and wildfires.

The research analyzed six decades of historical daily climate records and employed climate models to project future trends. Summer was defined as the onset of temperatures in the hottest 25 percent of the year and winter as temperatures in the coldest 25 percent. The number of summer days in the Northern Hemisphere increased from 78 to 95 between 1952 and 2011.