El Nino, as characterized by above average sea surface temperatures in the equatorial tropical Pacific, is the largest source of natural climate variability from sea- sonal to interannual scales and can profoundly res...El Nino, as characterized by above average sea surface temperatures in the equatorial tropical Pacific, is the largest source of natural climate variability from sea- sonal to interannual scales and can profoundly reshape the global weather patterns. Currently, the tropical Pacific Ocean appears to be primed for a potentially significant El Nino event, and some similarities exist between the oce- anic and atmospheric states in early 2014 compared to the observations shortly before the onset of the 1997/1998 Super El Nino event. For example, as one of the most important early signs of El Nino, a splitting eastbound propagation of the subsurface warm water is evident over the equatorial Pacific since January 2014. In this study, the pulses of subsurface warm water are reflected by the Kel- vin waves over the equatorial Pacific estimated from the satellite altimetry data. Results show that the current (i.e., March 2014) Kelvin wave over the equatorial Pacific has achieved the largest amplitude compared to those in the corresponding period prior to the E1 Nifio events since the availability of satellite altimetry, and is even significantly larger than the one that preceded the 1997/1998 Super El Nifio event. As the Kelvin waves can help induce El Nino conditions within about 2--4 months, the current fastest/ strongest eastbound propagation of subsurface warm water indicates that the likelihood of an El Nino event will sig- nificantly increase during the next several months in 2014.展开更多
基金supported by the National Program for Support of Top-notch Young Professionalsthe National Basic Research Program of China(2012CB417404)the ‘‘Western Pacific Ocean System:Structure,Dynamics and Consequences’’ Project of the Chinese Academy of Sciences(WPOS:XDA10010405)
文摘El Nino, as characterized by above average sea surface temperatures in the equatorial tropical Pacific, is the largest source of natural climate variability from sea- sonal to interannual scales and can profoundly reshape the global weather patterns. Currently, the tropical Pacific Ocean appears to be primed for a potentially significant El Nino event, and some similarities exist between the oce- anic and atmospheric states in early 2014 compared to the observations shortly before the onset of the 1997/1998 Super El Nino event. For example, as one of the most important early signs of El Nino, a splitting eastbound propagation of the subsurface warm water is evident over the equatorial Pacific since January 2014. In this study, the pulses of subsurface warm water are reflected by the Kel- vin waves over the equatorial Pacific estimated from the satellite altimetry data. Results show that the current (i.e., March 2014) Kelvin wave over the equatorial Pacific has achieved the largest amplitude compared to those in the corresponding period prior to the E1 Nifio events since the availability of satellite altimetry, and is even significantly larger than the one that preceded the 1997/1998 Super El Nifio event. As the Kelvin waves can help induce El Nino conditions within about 2--4 months, the current fastest/ strongest eastbound propagation of subsurface warm water indicates that the likelihood of an El Nino event will sig- nificantly increase during the next several months in 2014.