NASA, WMO, NOAA, UK Met Office: 2018 was 4th hottest year on record

NASA, WMO, NOAA, UK Met Office: 2018 was 4th hottest year on record

By Elisa Jiménez Alonso

According to independent analyses from the U.S. National Aeronautics and Space Administration (NASA), U.S. National Oceanic and Atmospheric Administration (NOAA), the UK Met Office and the World Meteorological Organization (WMO) 2018 ranks as the fourth warmest year on record globally – a clear sign of long-term climate change associated with a record high in atmospheric concentrations of greenhouse gases.

In 2018, global temperatures were about 0.83° C warmer than the 1951-1980 mean according to scientists from NASA’s Goddard Institute for Space Studies (GISS). 2018 sits just behind 2015, 2016, and 2017; collectively, the past five years have been the warmest years on record. Nine of the ten warmest years have occurred since 2005.

This line plot shows yearly temperature anomalies from 1880 to 2018, with respect to the 1951-1980 mean, as recorded by NASA, NOAA, the Japan Meteorological Agency, the Berkeley Earth research group, and the Met Office Hadley Centre (UK). Though there are minor variations from year to year, all five temperature records show peaks and valleys in sync with each other. All show rapid warming in the past few decades, and all show the past decade has been the warmest. Credits: NASA’s Earth Observatory.

“The long-term temperature trend is far more important than the ranking of individual years, and that trend is an upward one,” said WMO Secretary-General Petteri Taalas. “The 20 warmest years on record have been in the past 22 years. The degree of warming during the past four years has been exceptional, both on land and in the ocean.”

This warming trend is not felt equally across the globe. The Arctic, for example experiences the highest rates of warming, which is especially visible through the rapid loss of sea ice. In warmer and drier climates, increasing temperatures can lead to longer fire seasons and extreme events like heatwaves or droughts. Large parts of Europe, New Zealand and parts of the Middle East and Russia reached record high temperatures in 2018. Record-high sea-surface temperatures were also measured in the southern Pacific Ocean and parts of the north and south Atlantic Ocean. “The impacts of long-term global warming are already being felt — in coastal flooding, heat waves, intense precipitation and ecosystem change,” said GISS Director Gavin Schmidt.

Cover image by NOAA’s National Centers for Environmental Information: Land & ocean temperature percentiles Jan-Dec 2018.

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