AGU: Geophysical Research Letters

 

Editors' Highlight

Interannual variations of tropical instability waves in the Atlantic and Pacific oceans

The tropical trade winds drive oceanic upwelling along the equator bringing cold water to the surface. In the Pacific and Atlantic Oceans, oscillations of the temperature front between the cold equatorial water and warmer water farther poleward, called tropical instability waves (TIWs), propagate westward in both basins. Noting that TIWs influence oceanic heat balances, Wu and Bowman (2007) studied how these waves interact with interannual variations of sea surface temperature in the Atlantic and Pacific basins. Using 8 years of data from the Tropical Rainfall Measuring Mission (TRMM) satellite, the authors found that the sea surface temperature signature of TIWs in the Pacific Ocean is strongest during the phase of the El Niño–Southern Oscillation cycle when cold waters persist in the eastern Pacific and is weakest when El Niño warms the waters in the eastern Pacific. Similar patterns occur in the Atlantic Ocean through TIW interactions with Atlantic low-frequency variability. The authors expect that interannual variations in sea surface temperature due to TIW activity produce interannual variations in the behavior of the regional atmosphere.

View abstract

View full article (Subscription required)