Temperature Trends in the Lower Atmosphere - Understanding and Reconciling Differences

observed Changes Surface Globally, as well as in the tropics, the temperature of the air near the Earth’s surface has increased since 1958, with a greater rate of increase since 1979. All three surface temperature data sets are consistent in these conclusions. • Globally, temperature increased at a rate of about 0.12oC per decade since 1958, and about 0.16oC per decade since 1979. • In the tropics, temperature increased at a rate of about 0.11oC per decade since 1958, and about 0.13oC per decade since 1979. • Most, if not all of the surface temperature increase since 1958 occured starting around the mid-1970s, a time coincident with a previously identified abrupt climate shift. However, there does not appear to be an abrupt rise in temperature at this time, rather the major part of the rise seems to occur in a more gradual fashion.