The Observation And Study On The Uppper Troposphere And Lower Stratosphere Water Vapor And Ozone Over Tibetan Plateau And Its Adjoint Regions

This paper contains three aspects work:1) The observation and study on the upppertroposphere and lower stratosphere(UT-LS) water vapor and ozone vertical distribution withballoon-borne Cryogenic Frost point Hygrometer (CFH) and Electronic Chemistry Cell (ECC)over Tengchong Yunnan in August2010;2) The observation and study on the UT-LS watervapor and ozone vertical distribution with balloon-borne Cryogenic Frost point Hygrometer(CFH), RS92and Electronic Chemistry Cell (ECC) over Naqu Tibet in July-August2011.According to the existing literature, taking into account the time-lag error and solar radiationerror, this paper corrected the RS92measurement of water vapor and compared the correctedRS92data to CFH data;3) This paper corrected the RS92measurement of water vapor inDali Yunnan, Litang Sichuan and Gaize Tibet in2008JICA project, obtained and analysedthe water vapor data in UT-LS. Several conclusions are listed as followings:1)The UT-LS water vapor and ozone abundance are10.4±2.4ppmv and252.1±92.4ppbv at14-20km in Tengchong respectively, and13.1±6.5ppmv and294.5±13.2ppbv at14-20km in Naqu respectively.2) Our observed experience shown that: The CFH is a kind of radiosonde which issuitable to measure water vapor in UT-LS with low temperature and low humidityenvironment, its measurement in the lower most troposphere is most likely a slight wet bias.Comparing with CFH, a preliminary comparison reveals a large dry bias produced by theconventional radiosonde. The value of PW is not sensitive to the water vapor changes in theUT-LS. MLS water vapor data agrees on average with CFH measurements at pressures of82hPa. At100hPa the mean difference is7.3%±26%. At higher pressures the variabilityincreases with increasing pressure.3) The corrected RS92measurements indicate a1.69%and0.6%RH wet bias relative toCFH at5-10km and10-15km respectively. The corrected RS92measurements canaccurately reflect the UT-LS water vapor abundance over Tibetan Plateau. The correctedRS92measurements showd that: the troposphere to the UT-LS heights water vaporconcentration has an increase trend from spring to summer over Tibetan Plateau and itsadjoint regions. The UT-LS water vapor abundance increased by an average of2-4ppmv inJuly relative to March. The tropopause temperature decreased by an average of4-6K in Julyrelative to March in Litang and Gaize. But the transport of water vapor from the uppertroposphere to lower stratosphere increased. MLS water vapor data agrees on average withRS92measurements in order of magnitude. But the difference is large over the middle and upper troposphere. The RS92observation value in Dali and Litang is significantly higherthan the value of the MLS.4) MLS v2.2water vapor data agrees on average with CFH measurements at pressuresof82hPa and smaller to within2.5%±11.7%. At100hPa the mean difference is7.3%±26%.At higher pressures the variability increases with increasing pressure. The mean differenceindicates a39%±63%wet bias at215hPa,15.8±64dry bias at261hPa, and35.6%±123%wet bias in316hPa. The ECC column-integrated ozone measurements value is lower thanboth Brewer and OMI value.