Tropical Connections Along the Eastern Pacific During the 2014-16 El Niño and "Warm Anomaly" Events
Event: 2016 Ocean Surface Topography Science Team Meeting
Session: Science II: From large-scale oceanography to coastal and shelf processes
Presentation type: Type Poster
Altimeter and atmospheric model fields are used to describe the temporal evolution of alongshore geostrophic transports, winds and sea surface height (SSH) signals in the eastern Pacific Ocean next to North and South America between the Equator and mid-latitudes during 2014-2016. The development of the partial and complete El Niño events during 2014 and 2015 are described and compared to 1997-1998. These display a similar structure during 1997 and 2015 in the appearance of two pulses of high sea level and poleward transports (in boreal spring and autumn) that progress from the Equator into both hemispheres. Examination of coherence between both hemispheres is useful in identifying the signals that are not simple responses to local forcing. During 2014, only the first pulse was realized. In the Northern Hemisphere, however, the 2014 signals did progress as far as Baja California and may have contributed to the "warm anomaly" that appeared in summer along that region. An enhanced SSH data set that blends daily altimeter and tide gauge fields (ALT+TG) is used to examine in more detail the progression (or lack thereof) of SSH and alongshore transport signals next to the coast between the Mexican and Canadian borders during these years. Other moderate ENSO signals are also evident in the 1993-2016 period and these are also compared to the more "canonical" 1997 and 2015 events.