Xiaoqing Wu
Professor
Atmospheric Sciences
Ph.D. UCLA , 1992
M.S. Institute of Atmospheric Physics, Chinese Academy of Sciences, 1986
B.S. Hangzhou University, 1983

Department of Geological & Atmospheric Sciences
Iowa State University
3010 Agronomy Hall
Ames, IA  50011-1010

phone: (515) 294-9872
Fax: (515) 294-2619
office: 3011 Agronomy Hall
email: wuxq@iastate.edu


  Research

My research interests include numerical modeling, diagnostic,and theoretical studies to understand convection, cloud, radiation and precipitation processes and to improve their representation in general circulation models (GCMs) for predicting future climate. Studying and modeling of cloud systems are motivated by their profound effects on the global circulation, radiation budget and surface temperature, and the need for improved climate models and data for policy makers to determine safe levels of greenhouse gases for the Earth system. Cloud, radiation and precipitation processes are key components of the global water and energy cycle and operate on a wide range of time and space scales. Convection and clouds affect atmospheric temperature, moisture and wind fields through the release of latent heat; the redistributions of heat, moisture and momentum; and the precipitation. Clouds strongly affect the planetary energy budget and surface temperature through the reflection of sunlight, the absorption of infrared radiation from the surface and the emission of radiation to the surface as part of greenhouse effect. Since individual clouds have a spatial scale of less than 10 km that is much smaller than the conventional grid size of several hundred kilometers in climate and weather prediction models, they must be quantitatively formulated in terms of resolved variables in the prognostic equations of temperature, moisture and wind. Deriving such formulations for convection and clouds has been a major challenge for the climate modeling community due to the lack of observations of cloud and microphysical properties. To address this problem, my collaborators at NCAR and I have developed a cloud-resolving model (CRM) which resolves individual clouds but covers a large horizontal domain to generate cloud-scale datasets. The diagnostic and theoretical studies applying the high-resolution datasets generated by the CRM have lead to the improved representation of convection and cloud-radiation interaction in the climate models, and the improved simulations of global climate mean state and variability.
Research Projects

Wu, X., and X.-Z. Liang (Co-PI), 2002-2006: Application of Seasonal CRM Integrations to Develop Statistics and Improved GCM Parameterization of Subgrid Cloud-Radiation Interactions. DOE/ARM.

Wu, X., G.J. Zhang (Co-PI), and R.W. Arritt (Co-I), 2004-2008: Evaluating the Representation and Impact of Convective Momentum Transport in CCSM Atmosphere Model. DOE/CCPP.
 

Wu, X., and Qilong Min (Co-I), 2008-2011: Understanding and Improving CRM and GCM Simulations of Cloud Systems with ARM Observations. DOE/ARM.

  Teaching

Atmosperic Physics I (Mteor 341)
Atmosperic Physics II (Mteor 342)
Atmosperic Physics (Mteor 542)

  Refereed papers

Wu, X., and X. Li, 2008: A review of cloud-resolving model studies of convective processes. Advances in Atmospheric Sciences, in press.

Wu, X., S. Park, Q. Min, 2008: Seasonal variation of cloud systems over ARM SGP. J. Atmos. Sci., in press.

Song, X., X. Wu, G.J. Zhang, and R. Arritt, 2008: Dynamical effects of convective momentum transports on global climate simulations. J. Climate, 21, 180-194.

Wu, X., L. Deng, X. Song, G. Vettoretti, W. R. Peltier, and G. J. Zhang, 2007: Impact of a modified convective scheme on the MJO and ENSO in a coupled climate model. Geophys. Res. Lett. 34, L16823, doi:10.1029/2007GL030637.

Wu, X., L. Deng, X. Song, and G.-J. Zhang, 2007: Coupling of convective momentum transport with convective heating in global climate simulations. J. Atmos. Sci., 64, 1334-1349.

Wu, X., and X.-Z. Liang, and S. Park, 2007: Cloud-resolving model simulations over the ARM SGP. Mon. Wea. Rev., 135, 2841-2853.

Grabowski, W.W., X. Wu, and Co-authors, 2006: Daytime convective development over land: A model intercomparison based on LBA observations. Quart. J. Roy. Meteor. Soc., 132, 317-344.

Wu, X., and S. Guimond, 2006: Two- and three-dimensional cloud-resolving model simulations of the mesoscale enhancement of surface heat fluxes by precipitating deep convection. J. Climate, 19, 139-149.

Wu, X., and X.-Z. Liang, 2005: Radiative effects of cloud horizontal inhomogeneity and vertical overlap identified from a month-long cloud-resolving simulation. J. Atmos. Sci., 62, 4105-4112.

Wu, X., and X. Liang, 2005: Effect of subgrid cloud-radiation interaction on climate simulations. Geophys. Res. Lett., 32, L24806, doi:10.1029/2005GL024432.

Liang, X.-Z., and X. Wu, 2005: Evaluation of a GCM subgrid cloud-radiation interaction parameterization using cloud-resolving model simulations. Geophys. Res. Lett., 32, L06801, doi:10.1029/2004GL022301.

Xu, K.-M., X. Wu, and Co-authors, 2005: Modeling springtime shallow frontal clouds with cloud-resolving and single-column models, J. Geophys. Res., 110, D15S04, doi:10.1029/2004JD005153.

Xie, S., X. Wu, and Co-authors, 2005: Simulations of midlatitude frontal clouds by SCMs and CRMs during the ARM March 2000 cloud IOP. J. Geophys. Res., 110, D15S03, doi:10.1029/2004JD005119.

Wu, X., X.-Z. Liang, G.-J., Zhang 2003: Seasonal migration of ITCZ precipitation across the equator: Why can't GCMs simulate it? Geophys. Res. Lett., 30(15), 1824, doi:10.1029/2003GL017198.

Zhang, G.-J., and X. Wu, 2003: Convective momentum transport and perturbation pressure field from a cloud-resolving model simulation. J. Atmos. Sci., 60, 1120-1139.

Wu, X., M. W. Moncrieff, P. Minnis, and D. R. Doelling, 2002: Reply. J. Atmos. Sci. (The reply is not published because comment is withdrawn).

Wu, X., 2002: Effects of ice microphysics on tropical radiative-convective-oceanic quasi-equilibrium states. J. Atmos. Sci., 59, 1885-1897.

Wu, X., and M. W. Moncrieff, 2001: Sensitivity of single-column model solutions to convective parameterizations and initial conditions. J. Climate, 12, 2563-2582.

Wu, X., and M. W. Moncrieff, 2001: Long-term behavior of cloud systems in TOGA COARE and their interactions with radiative and surface processes. Part III: Effects on the energy budget and SST. J. Atmos. Sci., 58, 1155-1168.

Mapes, B., and X. Wu, 2001: Convective eddy momentum tendencies in long cloud-resolving model simulations. J. Atmos. Sci., 58, 517-526.

Yano, J.-I., M. W. Moncrieff, and X. Wu, 2001: Wavelet analysis of simulated tropical convective cloud systems. Part II: Decomposition of convective-scale and mesoscale structure. J. Atmos. Sci., 58, 868-876.

Yano, J.-I., M. W. Moncrieff, X. Wu, and M. Yamada, 2001: Wavelet analysis of simulated tropical convective cloud systems. Part I: Basic analysis. J. Atmos. Sci., 58, 850-867.

Wu, X., M. W. Moncrieff, and K. A. Emanuel, 2000: Evaluation of large-scale forcing during TOGA COARE for cloud-resolving models and single-column models. J. Atmos. Sci., 57, 2977-2985.

Naveau, P., M. W. Moncrieff, J.-I. Yano, and X. Wu, 1999: Exploratory statistical analysis of tropical oceanic convection using discrete wavelet transforms. Studies in the Atmospheric Sciences, L. M. Berliner, D. Nychka, and T. Hoar, Ed., Springer-Verlag New York Inc., 121-136.

Wu, X., and M. A. LeMone, 1999: Fine structure of cloud patterns within the intraseasonal oscillation during TOGA COARE. Mon. Wea. Rev., 127, 2503-2513.

Grabowski, W. W., X. Wu, and M. W. Moncrieff, 1999: Cloud resolving modeling of tropical cloud systems during Phase III of GATE. Part III: Effects of cloud microphysics. J. Atmos. Sci., 56, 2384-2402.

Wu, X., W. D. Hall, W. W. Grabowski, M. W. Moncrieff, W. D. Collins, and J. T. Kiehl, 1999: Long-term behavior of cloud systems in TOGA COARE and their interactions with radiative and surface processes. Part II: Effects of ice microphysics on cloud-radiation interaction. J. Atmos. Sci., 56, 3177-3195.

Wu, X., and M. W. Moncrieff, 1999: Effects of sea surface temperature and large-scale dynamics on the thermodynamic equilibrium state and convection over the tropical western Pacific. J. Geophys. Res., 104, 6093-6100.

Grabowski, W. W., X. Wu, M. W. Moncrieff, and W. D. Hall, 1998: Cloud resolving modeling of tropical cloud systems during Phase III of GATE. Part II: Effects of resolution and the third spatial dimension. J. Atmos. Sci., 55, 3264-3282.

Wu, X., W. W. Grabowski, and M. W. Moncrieff, 1998: Long-term behavior of cloud systems in TOGA COARE and their interactions with radiative and surface processes. Part I: Two-dimensional Modeling Study. J. Atmos. Sci., 55, 2693-2714.

Wu, X., 1998: Interactions of tropical convection with radation and surface processes in a cloud-resolving model. A contributed paper in Chinese with English Abstract in the book of 'East Asian Monsoon and Torrential Rain in China'. 385-405.

Grabowski, W. W., X. Wu and M. W. Moncrieff, 1996: Cloud resolving modeling of tropical cloud systems during Phase III of GATE. Part I: Two-dimensional experiments. J. Atmos. Sci., 53, 3684-3709.

Wu, X., and M. W. Moncrieff, 1996: Collective effects of organized convection and their approximation in general circulation models. J. Atmos. Sci., 53, 1477-1495.

Wu, X., and M. Yanai, 1994: Effects of vertical wind shear on the cumulus transport of momentum: Observations and parameterization. J. Atmos. Sci., 51, 1640-1660.

Wu, X., 1994: Diagnostic and semiprognostic studies of cumulus effects in the presence of mesoscale circulations. Mon. Wea. Rev., 122, 652-670.

Wu, X., 1993: Effects of cumulus ensemble and mesoscale stratiform clouds in midlatitude convective systems. J. Atmos. Sci., 50, 2496-2518.

Wu, X., 1992: Effects of mesoscale convective organization and vertical wind shear on the cumulus-environment interaction. Ph.D. dissertation, Dept. of Atmospheric Sciences, UCLA, Los Angeles, CA 90024, 221 pp.

Sui, C.-H., M.-D. Cheng, X. Wu and M. Yanai, 1989: Cumulus ensemble effects on the large-scale vorticity and momentum fields of GATE. Part II: Parameterization. J. Atmos. Sci., 46, 1609-1629.