Atlantic Meridional Transport

Observed From Space

Preliminry Results

W. Timothy Liu and Xiaosu Xie

Heat TransportWater TransportMean and Seasonal Variation

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Center of cyclonic currents

Ekman water transport

Ekman heat transport

Sato, Polito, & Liu, 2002: GRL, 29(17)

Sprintall & Liu, 2005: Oceanography, 18(4)

x: Zonal stress

Te: Potential temp. of Ekman layer

: Mean potential temp. of the water column

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Center of cyclonic currents

Meridional Heat Transport (MHT)

H: Heat content

: Horizontal heat flux

SW: Short wave radiation

LW: Long wave radiation

LH: Latent heat

SH: Sensible heat

By Greens theorem

Conservation of heat

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Center of cyclonic currents

Meridional Water Transport (MWT)

P: Precipitation

E: Evaporation

: Horizontal mass flux

R: River discharge

By Greens theorem

Conservation of water mass

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Total MHT at Atlantic

MHT from surface heat flux

MHT from heat storage change (Statistic-al model)

Intensification of poleward Ekman water transport from 1998 in the tropics

Pacific Ekman water transport

Anomaly

Total

Intensification of poleward Ekman heat transport from 1999 in the tropical Atlantic

Ekman heat transport anomaly 12N-14N SSM/I QuikSCAT

5S-8S

Ekman water transport in the subtropical Atlantic is correlated with NAO

Atlantic total northward water transport

Atlantic Ekman water transport Peak poleward transport in winter in the tropics

Intensification of poleward Ekman water transport from 1998 in the tropics

Atlantic Ekman water transport

Total

Anomaly

Ekman water transport anomaly 12N-14N SSM/I QuikSCAT

5S-8S

Intensification of poleward Ekman water transport from 1998 in the tropical Atlantic

Ekman water transport in the subtropical Atlantic is correlated with NAO

Summary

Spacebased data provide almost continuous spatial and temporal coverages for Ekman and total meridional transport for a decadeReality checks are neededWhat is the relation between surface Ekman transport in the total meridional transport need physical interpolation.

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