Areas of high pressure formed when air, which has risen in the tropics, subsides in subtropical areas. The air is warmed adiabatically as it descends; therefore rainfall is unlikely. The subtropical anticyclone over the North Atlantic, often called the ‘Azores’ or the ‘Bermuda high’, influences weather and climate over the eastern United States, western Europe, and north-western Africa (Davis et al. (1997) J. Climate 10, 4). Miyasaka and Nakamura (2005) J. Climate 18, 23 suggest a local land–sea–atmosphere feedback loop associated with a subtropical high.