evidence: The average increase in temperature since the 1970s has been around 1.4–1.5°C over all land, compared with around 1.0°C for the global average. According to ERA5, the average rate of increase over land is 0.32 ± 0.03°C[4] per decade from 1979 to 2023. The temperature rise over ice-free seas is about half that over land, but nevertheless accounts for about half of the rise in global average temperature, as the area of Earth’s surface covered by sea is much larger than the area covered by land. [...] Temperatures over the Arctic have risen much more rapidly than those over most of the rest of the globe. From the mid-1920s onwards, the datasets are generally in good agreement for temperatures over Arctic land. They show a warmer-than-average period in the 1930s and 1940s, cooler temperatures in the 1960s and 1970s that are only a little higher than the average for 1850–1900, and a rise in temperature of about 2.5°C since the mid-1970s. Current temperatures are around 1.8°C higher than those of the warmer-than-average years around 1940. The average rate of temperature increase over Arctic land, according to ERA5, is 0.65 ± 0.09°C per decade from 1979 to 2023. Long-term temperature change over the Arctic Ocean is more uncertain, but most datasets indicate a warming over the Arctic as a whole of close to 3°C since the late 1970s. This is a little larger than the warming over Arctic land alone and about three times larger than the corresponding global average warming over the same period.