The studies in this dissertation aim at advancing our scientific understandings about physical processes involved in the aerosol-cloud-precipitation interaction and quantitatively assessing the impacts of aerosols on the cloud systems with diverse scales over the globe on the basis of the observational data analysis and various modeling studies. As recognized in the Fifth Assessment Report by the Inter-government Panel on Climate Change, the magnitude of radiative forcing by atmospheric aerosols is highly uncertain, representing the largest uncertainty in projections of future climate by anthropogenic activities. By using a newly implemented cloud microphysical scheme in the cloud-resolving model, the thesis assesses aerosol-cloud interaction for distinct weather systems, ranging from individual cumulus to mesoscale convective systems. This thesis also introduces a novel hierarchical modeling approach that solves a long outstanding mismatch between simulations by regional weather models and global climate models in the climate modeling community. More importantly, the thesis provides key scientific solutions to several challenging questions in climate science, including the global impacts of the Asian pollution. As scientists wrestle with the complexities of climate change in response to varied anthropogenic forcings, perhaps no problem is more challenging than the understanding of the impacts of atmospheric aerosols from air pollution on clouds and the global circulation.

Autorentext

Yuan Wang

Education
Ph.D. in Atmospheric Sciences, Texas A&M University, Texas (2013)
B. S. in Computer Sciences, Fudan University, P.R. China (2007)

Research Interests
Aerosol-cloud interactions and their climate implication
Meso-scale and global climate modeling
Cloud physics and chemistry

Professional Experience
Postdoctoral Scholar, Jet Propulsion Laboratory, California Institute of Technology (2013 - Present)
Graduate Research Assistant, Texas A&M University (2007 - 2013)
Visiting Scholar, Pacific Northwest National Laboratory (2011 - 2011)

Selected Awards
Texas A&M University Distinguished Graduate Student Award (2014)
COAA-Springer Excellent Doctorate Theses Award (2014)
AGU Editor's Citation Award for Excellence in Scientific Refereeing (2013)
Best Student Oral Presentation Award, AMS Robert A. Duce Symposium (2013)
NASA Earth and Space Science Graduate Student Fellowship (2009 - 2012)
The Regents' Scholarship in Geoscience, Texas A&M University (2008)

Selected Publications
Wang, Y., M. Wang, R. Zhang, S.J. Ghan, Y. Lin, J. Hu, B. Pan, M. Levy, J. Jiang, M.J. Molina, Assessing the Effects of Anthropogenic Aerosols on Pacific Storm Track Using A Multi-Scale Global Climate Model, Proc. Natl Acad. Sci. USA, 111(19), 6894-6899 (2014).
Wang, Y., R. Zhang, R. Saravanan, Climatically modulated mid-latitude cyclones by Asian pollution from hierarchical modeling and observational analysis, Nature. Comm., 5, 3098 (2014).
Wang, Y., K.-H. Lee, Y. Lin, M. Levy, R. Zhang, Distinct Effects of Anthropogenic Aerosols on Tropical Cyclones, Nature. Clim. Change 4(5), 368-373 (2014)
M. Levy, R. Zhang, J. Zheng, A. Zhang, W. Xu, M. Gomez, Y. Wang, E. Olaguer, Measurements of nitrous acid (HONO) using ion drift-chemical ionization mass spectrometry during the 2009 SHARP fieldcampaign, Atmos. Environ., 94, 231-240 (2014)
M. Levy, R. Zhang, J. Zheng, H. Tan, Y. Wang, L. Molina, S. Takahama, L.M. Russell, G. Li, Measurements of submicron aerosols at the California-Mexico border during the Cal-Mex 2010 field campaign, Atmos. Environ., 88, 308-319 (2014)
M. Levy, R. Zhang, A. Khalizov, J Zheng, D. Collins, C. Glen, Y. Wang, X. Yu, W. Luke, J. Jayne, E. Olaguer, Measurements of submicron aerosols in Houston, Texas during the 2009 SHARP field campaign, J. Geophys. Res., 118(18), 10518-10534 (2013)
Wang, Y., A. Khalizov, M. Levy , R. Zhang, New Directions: Light Absorbing Aerosols and Their Atmospheric Impacts, Atmos. Environ. 81, 713-715 (2013)
Wang, Y., J. Fan, R. Zhang, R. Leung, C. Franklin, Improving Bulk Microphysics Parameterizations in Simulations of Aerosol Indirect Effects, J. Geophys. Res. 118, 1-19 (2013)
Fan, J., L. Leung , Z. Li , H. Morrison , H. Chen , Y. Zhou , Y. Qian , Y. Wang, Aerosol impacts on clouds and precipitation in eastern China-results from bin and bulk microphysics, J. Geophys. Res., 117, D00K36 (2012)
Wang, Y., Q. Wan, W. Meng, F. Liao, H. Tan, R. Zhang, Long-term impacts of aerosols on precipitation and lightning over the Pearl River Delta megacity area in China, Atmo. Chem. Phys., 11(23), 12421-12436 (2011)
Li, G., Y. Wang, K.-H. Lee, Y. Diao, R. Zhang, The effects of aerosols on development and precipitation of a mesoscale squall line, J. Geophys. Res., 114, D17205 (2009)
Li, G., Y. Wang, K.-H. Lee, Y. Diao, R. Zhang, Increased winter precipitation over the North Pacific from 1984-1994 to 1995-2005 inferred from the Global Precipitation Climatology Project. Geophys. Res. Lett., 35, L13821 (2008)
Li, G., Y. Wang, R. Zhang, Implementation of a two-moment bulk microphysics scheme to the WRF model to investigate aerosol-cloud interaction, J. Geophys. Res., 113, D15211 (2008)

Inhalt
Introduction.- Numerical model description.- Impacts of urban pollution on thunderstorms.- Aerosol effects on the stratocumulus and evaluations of microphysics.- Impacts of asian pollution outflows on the pacific storm.- Conclusions.