A study of the impact of synoptic weather conditions and water vapor on aerosol–cloud relationships over major urban clusters of China

Abstract. The relationships between aerosol optical depth (AOD), cloud cover (CC), and cloud top pressure (CTP) over three major urban clusters in China are studied under different sea level pressure (SLP) and water vapor (WV) regimes using a decade (2003–2013) of MODIS satellite-retrieved data. Over all urban clusters, for all SLP regimes, CC is found to increase with AOD, thus pointing out that the CC dependence on AOD cannot be explained by synoptic covariation, as approximated by SLP, alone. WV is found to have a stronger impact on CC than AOD. This impact is more pronounced at high aerosol load than at low aerosol load. Hence, studies of AOD–CC relationships, based on satellite data, will greatly overestimate the AOD impact on CC in regions where AOD and WV have similar seasonal variations, while they will probably underestimate the AOD impact in regions where AOD and WV have opposite seasonal variations. Further, this impact shows that the hydrological cycle interferes with the aerosol climatic impact and we need to improve our understanding of this interference. Our results also suggest that studies attributing CTP long-term changes to changes in aerosol load might have a WV bias.

[1]  P. Stier,et al.  Satellite observations of cloud regime development: the role of aerosol processes , 2013 .

[2]  D. Streets,et al.  A technology‐based global inventory of black and organic carbon emissions from combustion , 2004 .

[3]  B. Albrecht.  Aerosols, Cloud Microphysics, and Fractional Cloudiness , 1989, Science.

[4]  S. Rapsomanikis,et al.  Common summertime total cloud cover and aerosol optical depth weekly variabilities over Europe: Sign of the aerosol indirect effects? , 2015 .

[5]  Lorraine A. Remer,et al.  The invigoration of deep convective clouds over the Atlantic: aerosol effect, meteorology or retrieval artifact? , 2010 .

[6]  T. Blaschke,et al.  Variability of aerosol optical depth and their impact on cloud properties in Pakistan , 2014 .

[7]  T. Blaschke,et al.  Monitoring spatio-temporal variations in aerosols and aerosol-cloud interactions over Pakistan using MODIS data , 2010 .

[8]  S. Ghan,et al.  Aerosol optical depth increase in partly cloudy conditions , 2012 .

[9]  Norman G. Loeb,et al.  An Observational Study of the Relationship Between Cloud, Aerosol and Meteorology in Broken Low-Level Cloud Conditions , 2013 .

[10]  O. Boucher,et al.  Estimates of the direct and indirect radiative forcing due to tropospheric aerosols: A review , 2000 .

[11]  M. Chin,et al.  Global observations of aerosol‐cloud‐precipitation‐climate interactions , 2014 .

[12]  Min Min,et al.  Multi-sensor quantification of aerosol-induced variability in warm clouds over eastern China , 2015 .

[13]  U. Lohmann,et al.  Global indirect aerosol effects: a review , 2004 .

[14]  X. Xia,et al.  Positive relationship between liquid cloud droplet effective radius and aerosol optical depth over Eastern China from satellite data , 2014 .

[15]  Abhay Devasthale,et al.  Change in cloud-top temperatures over Europe , 2005, IEEE Geoscience and Remote Sensing Letters.

[16]  David G. Streets,et al.  Sulfur dioxide emissions in China and sulfur trends in East Asia since 2000 , 2010 .

[17]  H. Linderholm,et al.  Rain-season trends in precipitation and their effect in different climate regions of China during 1961–2008 , 2011 .

[18]  J. Hansen,et al.  Climate Effects of Black Carbon Aerosols in China and India , 2002, Science.

[19]  F. Bréon,et al.  Satellite-based estimate of aerosol direct radiative effect over the South-East Atlantic , 2013 .

[20]  H. Che,et al.  Spatio-temporal variation trends of satellite-based aerosol optical depth in China during 1980-2008 , 2011 .

[21]  Jing Zhao,et al.  Satellite observed aerosol-induced variability in warm cloud properties under different meteorological conditions over eastern China , 2014 .

[22]  M. Domrös,et al.  The climate of China , 1987 .

[23]  Yoram J. Kaufman,et al.  An Emerging Global Aerosol Climatology from the MODIS Satellite Sensors , 2008 .

[24]  David G. Streets,et al.  Aerosol trends over China, 1980-2000 , 2008 .

[25]  P. Stier,et al.  Rainfall‐aerosol relationships explained by wet scavenging and humidity , 2014 .

[26]  C. Bretherton,et al.  Clouds and Aerosols , 2013 .

[27]  Bin Wang,et al.  The Asian monsoon , 2006 .

[28]  François-Marie Bréon,et al.  Analysis of aerosol‐cloud interaction from multi‐sensor satellite observations , 2010 .

[29]  Zhanqing Li,et al.  Estimation of aerosol single scattering albedo from solar direct spectral radiance and total broadband irradiances measured in China , 2007 .

[30]  P. Stier,et al.  Wet scavenging limits the detection of aerosol effects on precipitation , 2015 .

[31]  Y. N. Ahammed,et al.  Spatio-temporal variations in aerosol optical and cloud parameters over Southern India retrieved from MODIS satellite data , 2012 .

[32]  W. Paul Menzel,et al.  Cloud and aerosol properties, precipitable water, and profiles of temperature and water vapor from MODIS , 2003, IEEE Trans. Geosci. Remote. Sens..

[33]  Frank Oldfield,et al.  The Climate of China , 1989 .

[34]  E. Vermote,et al.  The MODIS Aerosol Algorithm, Products, and Validation , 2005 .

[35]  Andrei P. Sokolov,et al.  Quantifying Uncertainties in Climate System Properties with the Use of Recent Climate Observations , 2002, Science.

[36]  Michael Q. Wang,et al.  An inventory of gaseous and primary aerosol emissions in Asia in the year 2000 , 2003 .

[37]  J. Norris,et al.  Meteorological bias in satellite estimates of aerosol‐cloud relationships , 2007 .

[38]  Michael Q. Wang,et al.  Black carbon emissions in China , 2001 .

[39]  P. Stier,et al.  Cloud fraction mediates the aerosol optical depth‐cloud top height relationship , 2014 .

[40]  David G. Streets,et al.  Primary anthropogenic aerosol emission trends for China, 1990–2005 , 2011 .

[41]  Mark Z. Jacobson,et al.  Microphysical and radiative effects of aerosols on warm clouds during the Amazon biomass burning season as observed by MODIS: impacts of water vapor and land cover , 2011 .

[42]  Reto Knutti,et al.  Constraints on radiative forcing and future climate change from observations and climate model ensembles , 2002, Nature.

[43]  Johannes Quaas,et al.  Interpreting the cloud cover – aerosol optical depth relationship found in satellite data using a general circulation model , 2009 .

[44]  S. Twomey.  Pollution and the Planetary Albedo , 1974 .

[45]  Adarsh Kumar.  Variability of aerosol optical depth and cloud parameters over North Eastern regions of India retrieved from MODIS satellite data , 2013 .

[46]  E. Feil,et al.  Climate Effects of Black Carbon Aerosols in China and India , 2002 .

[47]  J. Marshall Shepherd,et al.  Aerosol relationships to warm season clouds and rainfall at monthly scales over east China: Urban land versus ocean , 2008 .

[48]  Reto Knutti,et al.  Climate Forcing by Aerosols--a Hazy Picture , 2003, Science.

[49]  V. Ramanathan,et al.  Reduction of tropical cloudiness by soot , 2000, Science.

[50]  Philip Stier,et al.  Investigating relationships between aerosol optical depth and cloud fraction using satellite, aerosol reanalysis and general circulation model data , 2012 .

[51]  A. Ekman,et al.  Impact of meteorological factors on the correlation between aerosol optical depth and cloud fraction , 2010 .

[52]  Steven Platnick,et al.  Exploring the differences in cloud properties observed by the Terra and Aqua MODIS Sensors , 2009 .

[53]  V. Ramanathan,et al.  Aerosols, Climate, and the Hydrological Cycle , 2001, Science.

[54]  Zhanqing Li,et al.  Impact of aerosols on convective clouds and precipitation , 2012, Reviews of Geophysics.