The Large-Scale Energy Budget of the Arctic Mark C. SerrezeNational Snow and Ice Data Center (NSIDC)Cooperative Institute for Research in Environmental Sciences at the University of Colorado at Boulder

•Use NCEP and ERA-40 reanalysis to get monthly time changes in atmospheric energy storage, top of atmosphere radiation,vertically-integrated atmospheric energy flux convergenceand surface heat fluxes

•Key issue: ocean and atmosphere communicate through surface fluxes, but fluxes are quite uncertain, even on monthly timescales and averaged over large areas

•Use available oceanographic data to get time changes in ocean sensible heat storage, heat flux convergence and ice transport

Overview

Assess large-scale energy budgets of the the Arctic atmosphere and underlying ocean

Energy Budget of the Arctic Atmosphere/Ocean

Serreze et al., 2007

Big residual in atmos. budgetIn July. How much of this is contributed by poor surface fluxes versus problems in other terms?

I wish I knew

Summer: DOWN•Ice melt•Ocean gains sensible heat•Atmosphere stays cool

Strong seasonality in net surface heat flux

Autumn/Winter: UP•Ice growth•Ocean loses sensible heat•Heat goes to atmosphere

Getting a better handle in the basic surface budget:

• Spatial resolution needed: 1 deg. lat/long (100 km)

• Temporal resolution needed: monthly would do

• Desired accuracy: 10 Watts/sq. m? (depends on the term)

• How to validate reanalysis estimates? CERES also provides surface radiation fluxes, but how good are these? What can we learn through comparisons between different reanalyses? How does one best rectify point observations (e.g., SHEBA) with grid cell averages?