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Nicholas R. Nalli, William L. Smith, and Quanhua Liu

1. Introduction As discussed previously in Nalli et al. (2012 , 2013a) , accurate satellite observations (obs) and calculations (calc) of clear-sky, top-of-atmosphere (TOA) spectral radiances are necessary for retrieval of environmental data records (EDRs) from satellite infrared (IR) sounder and imager remote sensing systems. IR-based EDR physical retrieval algorithms are based upon the minimization of clear-sky obs minus calc (obs − calc, or equivalently from the forward modeling

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Tianmeng Chen, Jianping Guo, Zhanqing Li, Chuanfeng Zhao, Huan Liu, Maureen Cribb, Fu Wang, and Jing He

Abstract

Many efforts have been taken to investigate aerosol–cloud interactions from space, but only a few studies have examined the response of vertical cloud structure to aerosol perturbations. Three-dimensional cloud climatologies of eight different cloud types identified from the CloudSat level-2 cloud product during the warm season (May–September) in 2008–10 over eastern China were first generated and analyzed. Using visibility as a proxy for cloud condensation nuclei, in combination with satellite-observed radar reflectivity, normalized contoured frequency by altitude diagrams of the differences in cloud radar reflectivity Z profiles under polluted and clean conditions were constructed. For shallow cumulus clouds (shallow Cu) Z tends to be inhibited, and it is enhanced in the upper layers for deep cumulus (deep Cu), nimbostratus (Ns), and deep convective clouds (DCC) under polluted conditions. Overall, analyses of the modified center of gravity (MCOG) and cloud-top height (CTH) also point to a similar aerosol effect, except for the nonsignificant changes in MCOGs and CTHs in deep Cu. The impacts of environmental factors such as lower-tropospheric stability and vertical velocity are also discussed for these types of clouds. Although consistent aerosol-induced elevations in MCOGs and CTHs for Ns and DCC clouds are observed, the effect of meteorology cannot be completely ruled out, which merits further analysis.

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Andrew R. Jongeward, Zhanqing Li, Hao He, and Xiaoxiong Xiong

mean of the Level-3 daily product produces the Level-3 monthly mean product ( Hubanks et al. 2015 ). Data from MODIS Aqua are used, beginning in July 2002 and ending in December 2012. The upgrade from Collection 051 to 006 was aimed at “maintenance and modest improvement” and does not represent a major upgrade to algorithms or products ( Levy et al. 2013 ). Quality assurance products are also available and the results of trend analysis using this dataset will also be discussed. Unless otherwise

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Daniel Rothenberg and Chien Wang

existing activation parameterizations. The fourth- and fifth-order chaos expansions derived from the detailed parcel model are more accurate on average than two commonly used, physically based parameterizations from the literature ( Abdul-Razzak and Ghan 2000 ; Morales Betancourt and Nenes 2014 ). Additionally, the chaos expansions are all at least 10 times faster to evaluate than the MBN scheme and only about twice as expensive as the ARG scheme. A simple algorithm was suggested for evaluating a

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Romy Ullrich, Corinna Hoose, Ottmar Möhler, Monika Niemand, Robert Wagner, Kristina Höhler, Naruki Hiranuma, Harald Saathoff, and Thomas Leisner

aerosols were activated in the previous time bin calculated from the ice number concentration. Following the described algorithm, the INAS density for each bin is then calculated for each bin by Note that this approach is different from the cumulative INAS density calculation by, for example, Niemand et al. (2012) or Steinke et al. (2011) . The error propagation with uncertainties of ( Wagner and Möhler 2013 ) and yields a relative error for the INAS density of about 40%. c. Origin

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Jianjun Liu, Zhanqing Li, and Maureen Cribb

-infrared satellite measurements . J. Geophys. Res. , 107 , AAC 7-1 – AAC 7-2 , doi: 10.1029/2001JD000766 . Chang , F.-L. , and Z. Li , 2003 : Retrieving vertical profiles of water-cloud droplet effective radius: Algorithm modification and preliminary application . J. Geophys. Res. , 108 , 4763 , doi: 10.1029/2003JD003906 . Chen , Y.-C. , M. W. Christensen , G. L. Stephens , and J. H. Seinfeld , 2014 : Satellite-based estimate of global aerosol–cloud radiative forcing by marine warm clouds

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Jie Peng, Zhanqing Li, Hua Zhang, Jianjun Liu, and Maureen Cribb

, 2010 : Aerosol-induced changes of convective cloud anvils produce strong climate warming . Atmos. Chem. Phys. , 10 , 5001 – 5010 , doi: 10.5194/acp-10-5001-2010 . L’Ecuyer , T. S. , and J. H. Jiang , 2010 : Touring the atmosphere aboard the A-Train . Phys. Today , 63 , 36 – 41 , doi: 10.1063/1.3463626 . Levy , R. C. , L. A. Remer , S. Mattoo , E. F. Vermote , and Y. J. Kaufman , 2007 : Second-generation operational algorithm: Retrieval of aerosol properties over land

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Stacey Kawecki, Geoffrey M. Henebry, and Allison L. Steiner

Protection Agency (EPA) 2011 National Emissions Inventory (NEI; EPA 2011 ) regridded to the 4-km model domain. The NEI includes emissions from point, area, and mobile sources for 57 gas-phase species and 19 aerosol species (including sulfate, nitrate, salt, elemental carbon, and unspeciated PM 2.5 ). Biogenic emissions of isoprene are estimated using the Model of Emissions of Gases and Aerosols from Nature (MEGAN) emissions algorithm ( Guenther et al. 2006 ) and are used in the gas-phase chemistry

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Jiwen Fan, Yuan Wang, Daniel Rosenfeld, and Xiaohong Liu

satellites can measure cloud drop effective radius of the same clouds. For large-scale models the biggest problem with bin microphysics is the computational cost; therefore, development of new numerical algorithms to substantially reduce the computation cost can increase in the likelihood using such schemes in RGCMs. In addition, reducing the number of particle size distributions or number of bin sizes or using the hybrid moment and bin methods can decrease computational costs, but compromise with

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