As the Northern Hemisphere welcomes spring today, the Southern Hemisphere is marked with the first day of autumn.

The spring equinox will occur at 5:01 a.m. EDT on Thursday. Here's what to know about the start of the spring season.

H eat waves have gotten hotter in the Northern Hemisphere in recent decades. Home to about 90% of the world's population, with the largest fraction living in the mid-latitudes, more frequent and ...

Home to about 90% of the world's population, with the largest fraction living in the mid-latitudes, more frequent and more severe heat waves and droughts have occurred in the Northern Hemisphere ...