Data from NASA shows the Earth gradually heating up since the late 19th century. Since the year 2000, this trend seems to have accelerated as shown in the visualization of the data released. December 2020 was just 1.34° C colder than the average month recorded on Earth since 1880. In past decades, December was frequently 2 to 2.5° C colder.
As seen by the monthly temperatures of selected years since 1880, winter temperature is naturally below the multiyear mean of the reference period, which is a single figure showing the monthly mean temperature over a long period of time irrespective of seasons. Summer temperatures are naturally above the base period multiyear mean but have been diverging further and further from it.
The National Oceanic and Atmospheric Administration called the year 2020 the second-warmest on Earth since record began. According to NOAA data, 2016 exceeded the Earth's mean temperature most (calculated for the years from 1880 to 2015 and used as a reference period for the chart). According to NASA's calculations, 2020 and 2016 tied for the hottest year on record. In fact, the last seven years have been the seven warmest ever recorded, according to Gavin Schmidt, director or NASA's Goddard Institute for Space Studies.
The global data for near-surface temperatures comes from onshore weather stations as well as from ship, buoys and satellite measurements of the oceans. According to scientific findings, the continuing global warming will lead to changes in the strength, frequency, spatial extent and duration of extreme weather events.