Rotating globe showing sea-surface temperature with a cycling colour-coding, illustrating the transport of heat from the Equator to the poles. The ocean and atmosphere act to reduce temperature differences by transporting heat from the Equator to the poles. Without these heat engines, equatorial regions would be 10degC warmer, and the poles would be 20degC cooler than they are today. At low latitudes it is estimated that up to 74% of poleward heat transport is due to ocean currents.

Data source: European Remote Sensing Satellite (ERS) Along-Track Scanning Radiometer (ATSR) 10-day sea surface temperature grids from University College London (UCL) and Southampton Oceanography Centre (SOC), Rutherford Appleton Laboratory (RAL), Natural Environment Research Council (NERC), British National Space Centre (BNSC), European Space Agency (ESA).

Credit : Planetary Visions Ltd.