The year 2018 was marked with regular bouts of breaking news concerning rising temperatures across the globe including rapidly warming oceans and the Arctic losing 95% of its oldest ice. And today, the National Oceanic and Atmospheric Administration (NOAA) and National Aeronautics and Space Administration (NASA) released a statement that 2018 was the fourth-warmest year on record, after 2016, 2015, and 2017.
To obtain these measurements, NASA’s Goddard Institute for Space Science (GISS) gathered data from over 6,000 weather stations and instruments installed on ships, buoys, and at Antarctic research stations. Overall, 2018 was 0.83 °C (1.43 °F) warmer than average (called an “anomaly” due to its deviation from a baseline measurement of global temperatures spanning 1951 – 1980).
Because warming is regionally variable, not all parts of the world experienced warming equally. The Arctic region experienced the greatest warming in 2018, while sea ice loss in Greenland and Antarctica caused global sea level rise and extended periods of warming likely contributed to severe wildfire and extreme weather events.
The Japanese Meteorological Agency also declared 2018 to be the fourth-warmest year on record. According to the European Union’s Copernicus Climate Change Service, 2018 was more than 0.4 °C warmer than the 1981-2010 average and global concertations of the greenhouse gas, carbon dioxide, increased last year. Furthermore, over 90% of the warmest years on record, which spans 136 years, have occurred since 2001.
Although 2019 has gotten off to a cold start in the U.S., with Chicago experiencing cooler temperatures than Antarctica at the end of January, Australia is having one of its worst heat waves. And, the U.S. is currently setting twice as many record-breaking warm temperatures as it is cool ones. Thus, the Arctic polar vortex that has wandered south is not indicative of a cooling climate. In fact, warm air temperatures may be responsible for the polar vortex’s visit to the U.S. midwest. And, with a strong chance of an El Niño event in 2019, this year may be the warmest one yet.