Measurements near the Atmospheric Surface Flux Group tower at SHEBA: Near-surface conditions and surface energy budget

• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Arctic
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.530.2293; http://www.esrl.noaa.gov/psd/people/ola.persson/polar_studies/refereed/SHEBA_measurements.pdf

are used to describe the annual cycle of the near-surface environment and the surface energy budget (SEB). Comparisons with historical data and climatological estimates suggest that the SHEBA site was 3–8C warmer in March and April. The unique SHEBA profile measurements showed that the mean near-surface environment is strongly stable during 6 winter months, and near neutral or weakly stable during the other months. However, one-hour data show that neutral stratification does occur 25 % of the time during the winter. The monthly mean flux profiles suggest that turbulent processes cool the near-surface atmosphere during the winter and warm it during the summer, though the sign of the sensible heat flux is negative during both the winter and July. The SHEBA SEB calculation is unique in its nearly exclusive use of observed rather than derived values. The magnitude of the best estimate of the annual net observed surface energy surplus at SHEBA (8.2 W m2) was consistent with the observed surface ice and snowmelt and was in reasonable agreement with most previous estimates of the net annual SEB over the Arctic pack ice. However, the partitioning of the various components of the SEB differed in the SHEBA data. The SHEBA site had unusually large incoming longwave radiation in the fall