Figure 2.22

Ocean currents influence average annual temperatures. The Gulf Stream warms northern Europe as it delivers its tropical heat to the North Atlantic Ocean and then to the atmosphere. The ocean current off the coast of Alaska is much colder than the Gulf Stream. Tromsø, Norway, and Barrow, Alaska, are at the same latitude (roughly 71° north latitude) and are both coastal towns at sea level. Tromsø’s winters are less severe than Barrow’s because of the heat delivered to the atmosphere by the Gulf Stream. This satellite thermal infrared image was made December 13, 2013. Light gray shows areas with no data.

(Data from NASA)