January on Earth: hottest ever

The latest numbers are in for last month. The results show some of the hottest temperatures for a January ever recorded on planet Earth. As widely anticipated, global temperatures last month set a record. It even eclipsed January 1998 as the warmest January in the satellite temperature dataset. "In a sense that means that 2016 could end up being a 'race' to see if it will pass 1998 as the warmest year on record," says Dr. John Christy, director of the Earth System Science Center at the University of Alabama in Huntsville. Christy says while it might be only a fraction of a degree Celsius-- but it really adds up over time. The global climate trend since November of 1978 is an increase of  .12 degrees C per decade.

It was also the warmest January for the Northern Hemisphere as well. Beating out 2010 for the top spot with 0.70 degrees C above the Northern Hemisphere normal for January. The Southern Hempishere by itself only ranked in 4th place. And the tropics were actually cooler in January versus December, something climate scientists attribute to the on-going El Nino ocean conditions in the eastern Pacific Ocean where warmer than normal waters are shift to being up against the coastline of Central and South America. Despite being slightly cooler than the previous month, January in the tropical band surrounding Earth's equatorial regions still ranked as the second hottest January on record.

More about the study: satellite-based instruments measure the temperature of the atmosphere from the surface up to an altitude of a several miles above sea level. The study is part of an on-going joint project between the University of Alabama at Huntsville, NOAA, and NASA. The data is gathered by advanced microwave sounding units on satellites to get accurate temperature readings for almost all regions on Earth. This includes remote deserts, oceans and rain forests where reliable climate data just isn't available. Once monthly data reports are collected, they are placed in a public computer file for immediate access by atmospheric scientists in the U.S. and around the world. The satellite data goes back to 1978.