Interannual variations of tropical instability waves observed by the Tropical Rainfall Measuring Mission

Abstract

Eight years of microwave data from the Tropical Rainfall Measuring Mission (TRMM) satellite are used to study the interannual variations of tropical instability waves (TIWs) in the Pacific and Atlantic Oceans. SST signatures of TIWs in the Pacific Ocean are strongest during the cold phase of ENSO, when the cold tongue is most pronounced. The waves are weak during the warm phase of ENSO. A low‐frequency Atlantic air‐sea coupled equatorial mode affects TIW activity in the Atlantic in a similar fashion. Interannual variations in sea‐surface temperatures due to TIW activity can produce interannual variations in the atmospheric mesoscale response.