According to independent analyses by NASA and the National Oceanic and Atmospheric Administration (NOAA), Earth’s average global surface temperature in 2019 was the second warmest since modern record-keeping began in 1880.

Globally, 2019’s average temperature was second only to that of 2016 and continued the planet’s long-term warming trend: the past five years have been the warmest of the last 140 years. (https://www.ncdc.noaa.gov/sotc/global/201913)

“The decade that just ended is clearly the warmest decade on record,” said GISS Director Gavin Schmidt. “Every decade since the 1960s clearly has been warmer than the one before.”

Using climate models and statistical analysis of global temperature data, scientists have concluded that this increase has been driven mostly by increased emissions into the atmosphere of carbon dioxide and other greenhouse gases produced by human activities.

“We crossed over into more than 2 degrees Fahrenheit warming territory in 2015 and we are unlikely to go back. This shows that what’s happening is persistent, not a fluke due to some weather phenomenon: we know that the long-term trends are being driven by the increasing levels of greenhouse gases in the atmosphere,” Schmidt said.

Rising temperatures in the atmosphere and ocean are contributing to the continued mass loss from Greenland and Antarctica and to increases in some extreme events, such as heat waves, wildfires and intense precipitation.

NASA’s temperature analyses incorporate surface temperature measurements from more than 20,000 weather stations, ship- and buoy-based observations of sea surface temperatures, and temperature measurements from Antarctic research stations.

https://climate.nasa.gov/news/2945/nasa-noaa-analyses-reveal-2019-second-warmest-year-on-record/