The Earth experienced its fourth-hottest year in more than 136 years in 2018.
The UN's World Meterological Organisation said in November that 2018 was set to be the fourth warmest year in recorded history, stressing the urgent need for action to rein in runaway planetary warming. Nine of the 10 warmest years have been recorded since 2005, with the last five years comprising the five hottest.
"2018 is yet again an extremely warm year on top of a long-term global warming trend", said Goddard Institute director Gavin Schmidt.
Last year's average global surface temperature was 1.42 degrees Fahrenheit above the 20th-century average, according to NOAA. "It's the long-term trends that are having impacts on ice, on severity of droughts, on heat waves, on sea level rise and wildfires".
According to Schmidt, the warming has been driven in large part by increased emissions into the atmosphere of carbon dioxide and other greenhouse gases caused by human activities.
Even an increase of 1.5 degrees will have dire consequences, according to the United Nations science panel on climate change. Much of Europe had its warmest years on record.
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When asked to describe the scope of his panel's authority, Dingell was known to point to a NASA photo of Earth, taken from space. Dingell, a World War II-era Army veteran, will be interred at Arlington National Cemetery in Washington, D.C.
NOAA and NASA each analyze temperature measurements from thousands of sites around the world, including weather stations on land and ships and buoys spread across the world's oceans.
Since the 1880s, the average global surface temperature has risen about 2 degrees Fahrenheit (1 degree Celsius).
Arndt says 2018 "was an exclamation point, I think, on a trend that we're seeing toward more big rain, particularly in the eastern United States".
The human toll also was high, with 247 killed and many more injured in weather and climate disasters.
"The long-term temperature trend is far more important than the ranking of individual years, and that trend is an upward one", Petteri Taalas, secretary general of the World Meteorological Organization, told The Guardian. That would be warmer than the last four years.
But the USA did get soaked in 2018, says Deke Arndt, a climate scientist with NOAA. The release of the NASA/NOAA report was delayed by the U.S. government shutdown.