The record warm July continued a streak of 10 consecutive months dating back to October 2015 that have set new monthly high-temperature records. Compared to previous years, the warmer global temperatures last month were most pronounced in the Northern Hemisphere, particularly near the Arctic region.
The monthly analysis by the GISS team is assembled from publicly available data acquired by about 6,300 meteorological stations around the world, ship- and buoy-based instruments measuring sea surface temperature, and Antarctic research stations. The modern global temperature record begins around 1880 because previous observations didn’t cover enough of the planet.