Eastern Pacific tropical cyclones intensified by El Nino delivery of subsurface ocean heat
Journal
Nature
Journal Volume
516
Journal Issue
7529
Pages
82-U178
Date Issued
2014
Author(s)
Abstract
The El Ninõ Southern Oscillation (ENSO) creates strong variations in sea surface temperature in the eastern equatorial Pacific, leading to major climatic and societal impacts1,2. In particular, ENSO influences the yearly variations of tropical cyclone (TC) activities in both the Pacific and Atlantic basins through atmospheric dynamical factors such as vertical wind shear and stability3-6. Until recently, however, the direct ocean thermal control of ENSOon TCs has not been taken into consideration because of an apparent mismatch in both timing and location: ENSOpeaks in winter and its surface warming occurs mostly along the Equator, a region without TC activity. Here weshowthat El Ninõ-the warmphase of anENSOcycle-effectively discharges heat into the eastern North Pacific basin two to three seasons after its wintertime peak, leading to intensified TCs. This basin is characterized by abundant TC activity and is the second most activeTCregionintheworld 5-7.As a result of the time involved inocean transport, El Ninõ's equatorial subsurface 'heat reservoir', built up in boreal winter, appears in the easternNorth Pacific severalmonths later during peakTCseason (boreal summer and autumn). Bymeans of this delayed ocean transport mechanism, ENSO provides an additional heat supply favourable for the formation of strong hurricanes. This thermal control on intenseTCvariability has significant implications for seasonal predictions and long-term projections ofTCactivity over the eastern North Pacific. © 2014 Macmillan Publishers Limited. All rights reserved.
SDGs
Other Subjects
atmospheric dynamics; El Nino; El Nino-Southern Oscillation; heat transfer; sea surface temperature; seasonality; tropical cyclone; Article; El Nino; environmental parameters; forecasting; global climate; greenhouse effect; greenhouse gas; humidity; hurricane; Pacific Ocean; prediction; pressure gradient; priority journal; sea surface temperature; seasonal variation; surface property; thermocline; thermodynamics; thermoregulation; time series analysis; heat; season; theoretical model; water flow; Atlantic Ocean; Pacific Ocean; Pacific Ocean (East); Pacific Ocean (North); Cyclonic Storms; El Nino-Southern Oscillation; Hot Temperature; Models, Theoretical; Pacific Ocean; Seasons; Water Movements
Type
journal article