DETERMINING OF NEUTRAL AND UNSTABLE WIND PROFILES OVER BAGHDAD CITY

Abstract

This paper provides a comprehensive analysis of slow-response observations taken over the centre of Baghdad city (Bab Al-Mhadham area). Measurements were taken at two levels: 15 and 20 m and then wind speed profiles were derived according to atmospheric stability indicated by Richardson number in the lower part of planetary boundary layer. These profiles were constructed by logarithmic and power-exponent laws after checking estimated winds at the same heights by these laws with those observed. The estimated values of wind at these levels were in good agreement with observed values. Mean wind profiles calculated from both laws have logarithmic behavior especially in neutral conditions. They have the same shape and values at lower heights up to 50 m and then gradually deviate from each other over this height. Lastly, drag coefficient at each level was calculated and then its results found to be constant over neutral regime and increased with increasing instability.