Collaborative Research: A Heat Budget Analysis of the Arctic

Climate System

Mark C. Serreze, Andrew Barrett, Andrew Slater

CIRES/NSIDC, University of Colorado, Boulder, CO

Michael Steele

Polar Science Center, Applied Physics Laboratory, University of Washington, Seattle WA

Objective:

Examine the Arctic climate system from the integrating, yet

simplifying viewpoint of its large-scale heat budget

Draw From

ERA-40 and NCEP ReanalysesOceanographic ObservationsTerrestrial Observations

Satellite DataLand Surface Models

Coupled Ice-Ocean Models

What are the interplays between heat transports from lower latitudes, extreme seasonality in radiative forcing and heat exchanges between atmospheric and subsurface reservoirs that shape the observed state of the Arctic’s coupled atmosphere-land-ice-ocean system?

How are recent changes and projected future statesof the Arctic system reflected in components of the heat budget, and can we separate forcing from response?

What are the major uncertainties that hamper our ability to achieve a system-level understanding?

Science Questions

Heat Budget Equations:

• Atmospheric Column

ΔE/Δt = Fwall+Frad+Fsfc

• Ice/Ocean Land Column

ΔE*/Δt = Fo+Fi-Fsfc

Moist Static Energy Flux Latent Heat Flux

Atmospheric Heat Fluxes Across 70 deg. N

Annual Cycle of Atmospheric Terms from

ERA-40

Annual Cycle of Surface Terms from

ERA-40

Important Point: There are large seasonal variations inthe net surface flux. Acts as a negative feedback.

Jan 3.65633 Feb 2.95006 Mar 3.01168 Apr 2.92278 May 3.49785 Jun 4.90397 Jul 6.20166 Aug 7.25292 Sep 7.33829 Oct 7.01069Nov 6.52471 Dec 3.66975

MJ * 1015

Months

Arctic Ocean Sensible Heat Content

Arctic Ocean Sensible Heat Content

1000 MJ/m2 1000 MJ/m2

Annualmean

70-90 degN

J M M MJ S NF A J A O D

Courtesy M. Steele

Seasonality in the Sea Ice Cover

ERA-40 Net Surface Heat Flux (1979-2001)

Courtesy NSIDC

Energy Fluxes Across 70 deg. N

ERA-40 Residual Heat Flux (1979-2001)

Net Surface Heat Flux for the Arctic Ocean from ERA-40

Need to examine data from MERRA, CERES,coupled ice-ocean models and AOGCMs

Annual Mean Temperature Anomalies By Heightand Latitude: 2000 to 2005 (Referenced to 1979 to 1999)

Annual Mean Temperature Anomalies by Height and Latitude for 2005

(Referenced to 1979-2004)

Questions?

End of slideshow