The Observational Study On Wind Speed, Temperature And Humidity Profiles In The Surface Layer In Taklimakan Desert Hinterland

The Taklinmakan Desert is the second largest mobile desert in the world. As the largest desert in China,it is landlocked arid area of climate change is extremely sensitive regional response ,and it is also the source regions of sand and dust,and sandstorms,it has an important impact on China's climate and ecological environment. So far, as the hinterland of the Taklimakan Desert in recent formation of a lack of gradient, the desert hinterland in recent formation wind, temperature, wet gradient features extremely vertical structure, aerodynamic parameters of almost not involved.This article is in the use of the world's only mobile-depth 200 km above the desert hinterland of the Taklimakan desert hinterland of the atmospheric environment observation stations - Tazhong 80m observation tower in the gradient of the collection system in August and October in 2006, and January and April in 2007 four months of the gradient wind speed, temperature, humidity imformations, and unifies the weather station the conventional meteorology synchronization material. First toTazhong in 2006 summer, autumn and 2007 winter, spring's cloudless day average wind speed, temperature, humidity diurnalvariation characteristic carries on the analysis. The result include: (1) The average wind speed diurnalvariation has two peak values and two low values, the size and epoch various seasons has the difference, the surface layer lower level the wind speed is bigger than during the day at night, the upper formation is opposite, the intermediate level is stable, but on lower level various seasons have the difference highly.(2) The four seasons average temperature is the daytime is high, at night is low, this kind of change tendency is weaken upwardly by the ground.(3) Besides the winter, the average specific humidity continues in the daytime to reduce, and the closer ground the bigger reduces scope , the average of summer specific humidity is equal to spring's two times, and the diurnalvariation is obvious.Secondly,using the same materials analyze the Tazhong the surface layer cloudless day average wind speed, temperature, humidity profile characteristic as well as to under the April, 2007 spring typical cloudless day, the cloudy day, the floating dust and the sand storm weather wind speed, temperature, humidity profile characteristic carries on the contrastive analysis, The result include: (1) The cloudless day average wind speed daytime along with highly increases slowly, at night is quickly; The lower level wind speed is daytime bigger than at night, higher level daytime is smaller than at night.(2) Four seasons average temperature profiles performance for at night radiation pattern, early morning transition form, the daytime date shoots and the evening transition form and so on four types, morning and evening transition time have the difference in the season, the minimuma and maximum temperature appeared time in four seasons has a little difference.(3) The specific humidity along with increases highly at night in the winter, entire 80m surface layer performance for inverse humidity condition, inverse humidity appear generally in 0.5-lm,l-2m,32-47m,63-80m these four levels in other seasons,but each level appears in different time in four seasons.(4) The wind speed profile of the cloudy day is similar with the cloudless day, under the floating dust weather in daytime surface layer 20m the wind speed along with increases highly obviously, before the sand storm erupts, the wind speed to increase, after the transit, to weak.(5) The weather temperature profile of the floating dust change scope is small, the temperature during the sand storm transit continues to reduce, the temperature change scope in each level is consistent.(6) In the cloudy day ,above 32m highly is at the inverse humidity condition at night, in the floating dust the specific humidity is slightly smaller, the sand storm transit is continually the humidification process, but is not highly big changed with height.Finally, by using the semiemprical theory and the M-O sinilarty theory,fit the wind speed profile of Tazhong desert hinterland in the surface layer, The result include: (1) It is suitable the logarithm law under the neutral stratification's wind speed profile, when non-neutral stratification fits the relevance with the index to be better, the stratification is unstabler, n is smaller.(2) Using the M-O similarity theory, near neutral stratification is suitable "the logarithm + linearity" rule,Obtainsφ_M according to the actual material along with the stability distribution, obtainsβ_m when stable stratification andγ_m when unstable stratification in the surface layer in Tazhongdesert hinterland . In summerβ_m andγ_m respectively are 4.6 and 16.4, in winter respectivelyare 2.6 and 19.3.