第1个回答 2013-04-24
The paper by Lanzhou University in the semi-arid climate and environment observation station (SACOL) sun photometer CE-318 observation data, analyzed the change characteristics of atmospheric aerosol optical thickness, SACOL Å ngstr ö m index, the total precipitable water. The study found: aerosol optical characteristics of SACOL exhibits a periodic seasonal characteristic variation. AOD in the spring of AOD from 1:00 in the morning began to rise, to 4:00 reached the highest value, and then fell to 9:00 the lowest AOD value, the whole big spring, summer diurnal variation of AOD was Shuangfeng trend obviously, from 1:00 in the morning began to increase, and reached a maximum at 6:00, then began to decline to 8:00 reached a minimum, and then increases to 9 point hit a peak of second. Autumn and winter atmospheric stratification stability, the diurnal changes of AOD flat, autumn AOD average value for the minimum one year; seasonal change is remarkable, in the spring of April and reached the maximum at AOD average value, after the summer began to decline, fall September average minimum, and then gradually rise. The diurnal changes of PW flat, seasonal change is remarkable, in the summer of July reached a maximum value, after the summer decrease gradually, winter lowest in December, spring gradually rise. Å ngstr ö m wavelength exponent diurnal variation and daily variation of AOD basic consistent, the season of spring and summer and autumn and winter days, gentle change; seasonal change is remarkable, in the summer of July reached a maximum value, then decreased gradually until second year in the spring of April reached a minimum, and then gradually increased.