In situ water vapor and ozone measurements in Lhasa and Kunming during the Asian summer monsoon

The Asian summer monsoon (ASM) anticyclone circulation system is recognized to be a significant transport pathway for water vapor and pollutants to enter the stratosphere. The observational evidence, however, is largely based on satellite retrievals. We report the first coincident in situ measurements of water vapor and ozone within the ASM anticyclone. The combined water vapor and ozonesondes were launched from Kunming, China in August 2009 and Lhasa, China in August 2010. In total, 11 and 12 sondes were launched in Kunming and Lhasa, respectively. We present the key characteristics of these measurements, and provide a comparison to similar measurements from an equatorial tropical location, during the Tropical Composition, Cloud and Climate Coupling (TC4) campaign in July and August of 2007. Results show that the ASM anticyclone region has higher water vapor and lower ozone concentrations in the upper troposphere and lower stratosphere than the TC4 observations. The results also show that the cold point tropopause in the ASM region has a higher average height and potential temperature. The in situ observations therefore support the satellite‐based conclusion that the ASM is an effective transport pathway for water vapor to enter stratosphere.

[1]  L. Munchak,et al.  Relationship of cloud top to the tropopause and jet structure from CALIPSO data , 2011 .

[2]  Jonathon S. Wright,et al.  The influence of summertime convection over Southeast Asia on water vapor in the tropical stratosphere , 2011 .

[3]  J. Kar,et al.  CALIPSO detection of an Asian tropopause aerosol layer , 2011 .

[4]  Holger Vömel,et al.  Intercomparison of humidity and temperature sensors: GTS1, Vaisala RS80, and CFH , 2011 .

[5]  W. Randel.  Variability and Trends in Stratospheric Temperature and Water Vapor , 2013 .

[6]  Jorge Andres Diaz,et al.  Detailed structure of the tropical upper troposphere and lower stratosphere as revealed by balloon sonde observations of water vapor, ozone, temperature, and winds during the NASA TCSP and TC4 campaigns , 2010 .

[7]  Louisa Emmons,et al.  Asian Monsoon Transport of Pollution to the Stratosphere , 2010, Science.

[8]  A. Gettelman,et al.  Insights into Tropical Tropopause Layer processes using global models , 2007 .

[9]  A. Thompson,et al.  Assessment of the performance of ECC‐ozonesondes under quasi‐flight conditions in the environmental simulation chamber: Insights from the Juelich Ozone Sonde Intercomparison Experiment (JOSIE) , 2007 .

[10]  S. Massie,et al.  Transport above the Asian summer monsoon anticyclone inferred from Aura Microwave Limb Sounder tracers , 2007 .

[11]  G. Brasseur,et al.  A set of diagnostics for evaluating chemistry‐climate models in the extratropical tropopause region , 2007 .

[12]  H. Vömel,et al.  Accuracy of tropospheric and stratospheric water vapor measurements by the cryogenic frost point hygrometer: Instrumental details and observations , 2007 .

[13]  Jonathon S. Wright,et al.  Short circuit of water vapor and polluted air to the global stratosphere by convective transport over the Tibetan Plateau. , 2006, Proceedings of the National Academy of Sciences of the United States of America.

[14]  Michael J. Schwartz,et al.  Carbon monoxide measured by the EOS Microwave Limb Sounder on Aura: First results , 2005 .

[15]  Bin Wang,et al.  Convective outflow of South Asian pollution: A global CTM simulation compared with EOS MLS observations , 2005 .

[16]  G. Brasseur,et al.  Impact of monsoon circulations on the upper troposphere and lower stratosphere , 2004 .

[17]  A. O'Neill,et al.  The role of the south‐east Asian monsoon and other seasonal features in creating the ‘tape‐recorder’ signal in the Unified Model , 2004 .

[18]  Tang Jie,et al.  A meteorological analysis on a low tropospheric ozone event over Xining, North Western China on 26-27 July 1996 , 2004 .

[19]  P. Forster,et al.  A Climatology of the Tropical Tropopause Layer , 2002 .

[20]  Guoxiong Wu,et al.  The Bimodality of the 100 hPa South Asia High and its Relationship to the Climate Anomaly over East Asia in Summer , 2002 .

[21]  A. O'Neill,et al.  A mechanism for moistening the lower stratosphere involving the Asian summer monsoon , 1999 .

[22]  James M. Russell,et al.  Hemispheric asymmetries in water vapor and inferences about transport in the lower stratosphere , 1997 .

[23]  P. Mote,et al.  An atmospheric tape recorder: The imprint of tropical tropopause temperatures on stratospheric water vapor , 1996 .

[24]  M. Rodwell,et al.  A Model of the Asian Summer Monsoon. Part I: The Global Scale , 1995 .