What is average global temperature?
With winter in the southern hemisphere when it is summer in the north, with ups and downs in temperature weekly with weather, with variation throughout the day and night, the reported average global temperature is an average of composites. I recognize two alternate ways to attempt a measurement, one historically-used methods and one based on orbital satellites. Our romance with space-age equipment suggests the latter although that must be consistent with ground-based data.. (1) Stations all over the world measure air temperature at the surface and report their measurements, likely using the average between daily high and low; that value is adjusted for the surface area served by that station, and then a grand average is taken of those values. Arctic regions have fewer stations and are not as well represented in the total. About 3/4 of Earth’s surface is ocean and there are no permanent stations there (although there are bouys anchored here and there); however ocean surface temperatures
