Lidar Observations of Polar Mesospheric Clouds at South Pole: Seasonal Variations
نویسندگان
چکیده
Polar mesospheric clouds (PMCs) were observed above the geographic South Pole by an Fe Boltzmann temperature lidar from 11 Dec 99 to 24 Feb 00. During this 76-day period 297 h of observations were made on 33 different days and PMCs were detected 66.5% of the time. The mean PMC peak backscatter ratio, peak volume backscatter coefficient, total backscatter coefficient, layer centroid altitude, and layer rms width are 50.59 q2.33, 2.70 q0.12x10 -9 m-•sr -•, 3.61 q0.22x10 -6 sr -•, 85.49 q0.09 km, and 0.71 q0.03 km, respectively. The PMCs are highest near summer solstice when upwelling over the pole is strongest. The altitudes are 2-4 km higher than that typically observed elsewhere, including the North Pole. After solstice the mean altitudes decreases by about 64 m/day as the upwelling weakens.
منابع مشابه
Lidar studies of interannual, seasonal, and diurnal variations of polar mesospheric clouds at the South Pole
[1] Polar mesospheric clouds (PMC) were observed by an Fe Boltzmann temperature lidar at the South Pole in the 1999–2000 and 2000–2001 austral summer seasons. We report the study of interannual, seasonal, and diurnal variations of PMC using more than 430 h of PMC data. The most significant differences between the two seasons are that in the 2000– 2001 season, the PMC mean total backscatter coef...
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