Global average surface air temperatures only reflect the heat present in the atmospheric layer immediately above the land / ocean surface.
Not exact matches
Internal variability can
only account for ~ 0.3 °C change in
average global surface air temperature at most over periods of several decades, and scientific studies have consistently shown that it can not account for more than a small fraction of the
global warming over the past century.
It is not «conduction» but exchange of radiation; if you keep your hands parallel at a distance of some cm the right hand does not (radiatively) «warm» the left hand or vice versa albeit at 33 °C skin
temperature they exchange some hundreds of W / m ² (about 500 W / m ²) The solar radiation reaching the
surface (for 71 % of the
surface, the oceans) is lost by evaporation (or evapotranspiration of the vegetation), plus some convection (20 W / ²) and some radiation reaching the cosmos directly through the window 8µm to 12 µm (about 20 W / m ² «
global»
average);
only the radiative heat flow
surface to
air (absorbed by the
air) is negligible (plus or minus); the non radiative (latent heat, sensible heat) are transferred for
surface to
air and compensate for a part of the heat lost to the cosmos by the upper layer of the water vapour displayed on figure 6 - C.
The slowdown or «hiatus» in warming refers to the period since 2001, when despite ongoing increases in atmospheric greenhouse gases, Earth's
global average surface air temperature has remained more or less steady, warming by
only around 0.1 C.
However, for changes over time,
only anomalies, as departures from a climatology, are used, most commonly based on the area - weighted
global average of the sea
surface temperature anomaly and land
surface air temperature anomaly.