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. May 2020 was about 1.5° C hotter than the average month recorded on Earth since 1880.
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.
As confirmed by NASA and NOAA, the months from February to April 2020 were the second-warmest of their kind ever recorded, while January and May 2020 about tied with their 2016 counterparts (also the year when the hottest ever February, March and April occurred).
Scientists at NOAA are already projecting that 2020 will end up being the hottest year ever recorded. As of now, 2016 exceeded the Earth's mean temperature most (calculated for the years from 1980 to 2015 and used as a reference period for the chart).
2019, the current runner-up, was also really scorching and is - as of now - the second-hottest year ever recorded. As it stands, July 2019 was the warmest month ever recorded on Earth.
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.