Poleward atmospheric energy transports and their variability as evaluated from ECMWF reanalysis data

Autor(en)

Michael Mayer, Leopold Haimberger

Abstrakt

The vertically integrated global energy budget is evaluated with a direct and an indirect method (both corrected for mass inconsistencies of the forecast model), mainly using the European Centre for Medium-Range Weather Forecasts (ECMWF) Re-Analysis Interim (ERA-Interim) data. A new estimate for the net poleward total energy transport is given. Comparison to satellite-derived radiation data proves thatERA-Interimis better suited for investigation of interannual variations of the global energy budget than available satellite data since these either cover a relatively short period of time or are too inhomogeneous in time. While much improved compared to the 40-yr ECMWF Re-Analysis (ERA-40), regionally averaged energy budgets of ERA-Interim show that strong anomalies of forecasted vertical fluxes tend to be partly compensated by unrealistically large forecasted energy storage rates. Discrepancies between observed and forecasted monthly mean tendencies can be taken as rough measure for the uncertainties involved in the ERA-Interim energy budget. ElNiño-Southern Oscillation (ENSO) is shown to have large impact on regional energy budgets, but strong compensation occurs between the western and eastern Pacific, leading to only small net variations of the total poleward energy transports (similar magnitude as the uncertainty of the computations). However, Hovmöller longitude-time plots of tropical energy exports show relatively strong slowly eastward-moving poleward transport anomalies in connection with ENSO. Verification of these findings using independent estimates still needs to be done. © 2012 American Meteorological Society.

Organisation(en)

Institut für Meteorologie und Geophysik

Journal

Journal of Climate

Band

25

Seiten

734-752

Anzahl der Seiten

19

ISSN

0894-8755

DOI

https://doi.org/10.1175/JCLI-D-11-00202.1

Publikationsdatum

2012

Peer-reviewed

Ja

ÖFOS 2012

105204 Klimatologie

Link zum Portal

https://ucris.univie.ac.at/portal/de/publications/poleward-atmospheric-energy-transports-and-their-variability-as-evaluated-from-ecmwf-reanalysis-data(b5b5663a-a974-4a2f-9d8c-f0c9a337a33a).html