FN Archimer Export Format
PT J
TI Heat balance and eddies in the Peru-Chile current system
BT 
AF COLAS, Francois
   MCWILLIAMS, James C.
   CAPET, Xavier
   KURIAN, Jaison
AS 1:1;2:1;3:2;4:1;
FF 1:;2:;3:;4:;
C1 Univ Calif Los Angeles, Inst Geophys & Planetary Phys, Los Angeles, CA 90095 USA.
   IFREMER, Lab Phys Oceans, Plouzane, France.
C2 UNIV CALIF LOS ANGELES, USA
   CNRS, FRANCE
IF 4.23
TC 121
UR https://archimer.ifremer.fr/doc/00088/19892/17756.pdf
LA English
DT Article
DE ;Regional modelling;South-East Pacific;Heat Balance;Oceanic eddies;Regional climate
AB The Peru-Chile current System (PCS) is a region of persistent biases in global climate models. It has strong coastal upwelling, alongshore boundary currents, and mesoscale eddies. These oceanic phenomena provide essential heat transport to maintain a cool oceanic surface underneath the prevalent atmospheric stratus cloud deck, through a combination of mean circulation and eddy flux. We demonstrate these behaviors in a regional, quasi-equilibrium oceanic model that adequately resolves the mesoscale eddies with climatological forcing. The key result is that the atmospheric heating is large (> 50 W m(-2)) over a substantial strip > 500 km wide off the coast of Peru, and the balancing lateral oceanic flux is much larger than provided by the offshore Ekman flux alone. The atmospheric heating is weaker and the coastally influenced strip is narrower off Chile, but again the Ekman flux is not sufficient for heat balance. The eddy contribution to the oceanic flux is substantial. Analysis of eddy properties shows strong surface temperature fronts and associated large vorticity, especially off Peru. Cyclonic eddies moderately dominate the surface layer, and anticyclonic eddies, originating from the nearshore poleward Peru-Chile Undercurrent (PCUC), dominate the subsurface, especially off Chile. The sensitivity of the PCS heat balance to equatorial intra-seasonal oscillations is found to be small. We demonstrate that forcing the regional model with a representative, coarse-resolution global reanalysis wind product has dramatic and deleterious consequences for the oceanic circulation and climate heat balance, the eddy heat flux in particular.
PY 2012
PD JUN
SO Climate Dynamics
SN 0930-7575
PU Springer
VL 39
IS 1-2
UT 000305745100030
BP 509
EP 529
DI 10.1007/s00382-011-1170-6
ID 19892
ER

EF