Comparision of the NCEP/NCAR Reanalysis II winds with those observed over a complex terrain in lower atmospheric boundary layer

Abstract

NCEP/NCAR Reanalysis wind components at 1000 mb level in the grid of 12.5°-15°N and 77.5°-80°E has been investigated in comparison with National Atmospheric Research Laboratory (NARL) Doppler Sodar data in a complex terrain environment of an Indian Tropical Latitude station, Gadanki (13.45°N, 79.2°E) for a period of one year 2007. Influence of complex terrain effect on wind flow patterns derived by NCEP/NCAR reanalysis II in comparison with remote sensor (NARL Doppler Sodar) during stable and unstable conditions is discussed. Slope-valley circulations and mountain wave activity may be the possible reasons for the deviation observed between both the systems. During unstable conditions, correlation co-efficient of 0.78 in zonal and 0.66 in meridional wind components is reported high compared to 0.71 in zonal and 0.56 in meridional wind components for stable conditions. Zonal winds dominant over this station might be the cause for higher correlation in zonal case. © 2009 by the American Geophysical Union.