The present study deals with using long-term database for upper tropospheric water vapour (UTWV) variability studies over three tropical stations (Gadanki, Singapore and Truk), where different climatic conditions prevail. Over Gadanki (13.5°N, 79.2°E) strong seasonal variation in UTWV is revealed but not over Singapore (1.37°N, 103.98°E) and Truk (7.46°N, 151.85°E) except at 100 hPa. It is examined whether high resolution radiosonde measurements represent well the UTWV by comparing with different satellite based (Atmospheric Infrared Sounder (AIRS), Advanced Microwave Sounding Unit-B (AMSU-B) and Microwave Limb Sounder (MLS)) water vapour measurements. Very good comparison in the nature of variations of UTWV is observed between radiosonde data and satellite data, except over Singapore particularly with AIRS and MLS data, on long-term basis. An attempt is also made to examine the source for UTWV. A close relationship is found between UTWV and deep convection over Gadanki indicating that the source for UTWV is convection particularly during the summer monsoon season.
Similar content being viewed by others
References
Buehler S A and John V O 2005 A simple method to relate microwave radiances to upper tropospheric humidity; J. Geophys. Res. 110 D02110, doi: 10.1029/2004JD005111.
Buehler S A, Kuvatov M, John V O, Milz M, Soden B J, Jackson D L and Notholt J 2008 An upper tropospheric humidity dataset from operational satellite microwave data; J. Geophys. Res. 113 D14110, doi: 10.1029/2007JD009314.
Divakarla M G, Barnet C D, Goldberg M D, McMillin L M, Maddy E, Wolf W, Zhou L and Liu X 2006 Validation of atmospheric infrared sounder temperature and water vapour retrievals with matched radiosonde measurements and forecasts; J. Geophys. Res. 111 D09S15, doi: 10.1029/2005JD006116.
Forster E F and Shine K P 1999 Stratospheric water vapour changes as a possible contributor to observed stratospheric cooling; Geophys. Res. Lett. 2621 3309–3312, doi: 10.1029/1999GL010487.
Fueglistaler S, Dessler A E, Dunkerton T J, Folkins I, Fu Q and Mote P W 2009 Tropical tropopause layer; Rev. Geophys. 47 RG1004, doi: 10.1029/2008RG000267.
Hansen J, Lacis A, Rind D, Russell G, Stone P, Fung I, Ruedy R and Lerner J 1984 Climate sensitivity: Analysis of feedback mechanisms; In: Climate Processes and Climate Sensitivity (eds) Hansen J E and Takahashi T, AGU Geophysical Monograph 29, Maurice Ewing, Vol. 5. American Geophysical Union, pp. 130–163.
Intergovernmental Panel on Climate Change IPCC 2007 Climate Change 2007; The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change (eds) S Solomon et al., Cambridge University Press, Cambridge, UK.
John V O and Buehler S A 2005 Comparison of microwave satellite humidity data and radiosonde profiles: A survey of European stations; Atmos. Chem. Phys. 5 1843–1853, SRef-ID: 1680-7324/acp/2005-5-1843.
Linzen R S 1990 Some coolness concerning global warming; Bull. Am. Meteor. Soc. 71 288–299.
Moradi I, Buehler S A, John V O and Eliasson S 2010 Comparing upper tropospheric humidity data from microwave satellite instruments and tropical, radiosonde; J. Geophys. Res. 115 D24310.
Randel W J and Wu F 2006 Biases in stratospheric and tropospheric temperature trends derived from historical radiosonde data; J. Climate 19 2094–2104.
Read W G, Wu D L, Waters J W and Pumphrey H C 2004 Dehydration in the tropical tropopause layer: Implications from the UARS Microwave Limb Sounder; J. Geophys. Res. 109 D06110, doi: 10.1029/2003JD004056.
Read W G et al. 2007 Aura Microwave Limb Sounder upper tropospheric and lower stratospheric H2O and relative humidity with respect to ice validation; J. Geophys. Res. 112 D24, doi: 10.1029/2007JD008752.
Saunders R W, Hewison T J, Stringer S J and Atkinson N C 1995 The radiometric characterization of AMSU-B; IEEE Trans. Microwave Theory Tech. 434 760–771.
Soden B J and Bretherton F P 1993 Upper-tropospheric relative-humidity from the GOES 6.7 mm channel: Method and climatology for July 1987; J. Geophys. Res. 98 16,669–16,688.
Solomon S, Rosenlof K, Portmann R, Daniel J, Davis S, Sanford T and Plattner G-K 2010 Contributions of stratospheric water vapour to decadal changes in the rate of global warming; Science 327 1219–1223, doi: 10.1126/science.1182488.
Tsuda T, Venkat Ratnam M, Kozu T and Mori S 2006 Characteristics of 10-day Kelvin wave observed with radiosondes and CHAMP/GPS occultation during CPEA campaign April–May 2004; J. Meteorol. Soc. Japan 84A 277–293.
Vömel H et al. 2002 Balloon-borne observations of water vapour and ozone in the tropical upper troposphere and lower stratosphere; J. Geophys. Res. 107 4210, doi: 10.1029/2001JD000707.
Waters J W et al. 2006 The Earth Observing System Microwave Limb Sounder EOS MLS on the Aura satellite; IEEE Trans. Geosci. Remote Sens. 445 1075–1092, doi: 10.1109/TGRS.2006.87377.
Acknowledgements
The authors wish to thank the various data sources for providing satellite data through their FTP sites.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
BASHA, G., RATNAM, M.V. & MURTHY, B.V.K. Upper tropospheric water vapour variability over tropical latitudes observed using radiosonde and satellite measurements. J Earth Syst Sci 122, 1583–1591 (2013). https://doi.org/10.1007/s12040-013-0367-y
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s12040-013-0367-y