Land-Surface Atmosphere Interactions

Predicting the impacts of land-surface processes on regional weather, climate, and hydrology

In this relatively new research and application area, our objectives are to understand, through theoretical and observational studies, the complex interactions (including biophysical, hydrological, and biogeochemical interactions) between the land-surface and the atmosphere at micro- and meso-scales.

The ultimate goal is to integrate such knowledge into numerical mesoscale weather prediction and regional climate models in order to improve prediction of the impacts of land-surface processes on regional weather, climate, and hydrology. To achieve these objectives, a number of research and application studies are conducted.

Sponsors

CASES-97 (Cooperative Atmosphere Surface Exchange Study of '97)

The Cooperative Atmosphere-Surface Exchange Study 1997 field program (CASES-97) was conducted from late April-mid June 1997, look at the role of atmosphere-surface exchange in the diurnal cycle of the temperature and moisture field in the Walnut River Watershed in SE Kansas, and to improve the representation of the important processes in land-surface models. Flux and mean data from two aircraft (NOAA Twin Otter and University of Wyoming King Air) and 9 surface sites were supplemented with radiosondes, radar wind profilers from Argonne National Laboratory, and gage-corrected precipitation estimates from two radars (S-Pol and the Wichita WSR-88D).

IHOP (IHOP/NCAR Soil Moisture, Soil Temperature, and Vegetation Observation Network)

The boundary-layer portion of the International H2O Experiment (IHOP_2002) supports its overall goal to improve convective precipitation prediction through better use and representation of water vapor in numerical weather prediction (NWP) models through estimating surface water vapor and sensible heat fluxes, characterizing the influence of surface properties on boundary-layer heterogeneity, and understanding the role that these play in the initiation and evolution of convective precipitation systems. Data collection and analysis were designed to provide benchmarks to enable improvements in the representation of land-surface and boundary-layer processes in NWP models.

Sensors at site 6 during the CASES-97 field program.

Land-Surface Modeling (LSM)

RAL scientists work to understand, through theoretical and observational studies, the complex biophysical, hydrological, and bio-geochemical interactions between the land-surface and the atmosphere at micro- and mesoscales. The ultimate goal is to integrate such knowledge into numerical mesoscale weather prediction and regional climate models to improve prediction of the impacts of land-surface processes on regional weather, climate, and hydrology. Land surface modeling efforts were funded in FY06 by NSF, the Air Force Weather Agency (AFWA), NOAA, NASA, and DTRA.

Weather Research and Forecast (WRF) Model

The WRF/Noah LSM Coupled system consists of a large number of comprehensive terristrial data sets, their processing onto WRF grid through WRF/SI and Real routines, and the Unified Noah LSM as part of WRF physics package.

The following documents explain how to set up the WRF/SI/Real to acquire all surface, vegetation, soil data necessary to run the WRF/Noah coupled system. These information are probably most useful for users who want to modify these routines to ingest new land data and to modify the default WRF/Noah LSM configurations.

NCAR High-Resolution Land Data Assimilation System (HRLDAS)

Although the important role of soil moisture in the development of deep-convection has been recognized, it remains the most difficult variable to obtain because there is no routine high-resolution observation of soil moisture at the continental scale. Thus, a High-Resolution Land Data Assimilation System (HRLDAS) has been developed to support the WRF/Noah coupled land surface modeling system and ATEC range forecasts. It uses observed hourly precipitation, solar radiation derived from satellite, and analyzed surface wind and temperature to force a land-surface model to simulate the evolution of soil moisture.

HRLDAS produced volumetric surface soil moisture at 4-km resolution.

Urban Modeling Effort

Our goal is to develop an integrated, multi-scale urban modeling system for the Weather Research and Forecast (WRF) model to address various urban environmental issues.

Warm-Season Quantitative Precipitation Forecast (QPF)

Land surface properties (e.g., albedo, soil moisture, vegetation) modify the partition of latent heat (evaporation) and sensible heat fluxes, and boundary layer structures and stability, which collectively impacts convection initiation and precipitation.

Journal Publications

2008

Couvreux, F., F. Guichard, P. Austino, and F. Chen, 2007: Nature of the mesoscale boundary-layer height and water-vapor variability observed the 14 June 2002 during the IHOP 2002 campaign. Mon. Wea. Rev., in press.

Alapaty K., D. Niyogi, F. Chen, P. Pyle, A. Chandrasekar, N. Seaman, 2008: Development of the Flux-Adjusting Surface Data Assimilation System for Mesoscale Models, J. Appl. Meteorol. Clim., in press.

Trier, S., F. Chen, and K. Manning, M.A. LeMone, and C. Davis, 2008: Sensitivity of the Simulated PBL and Precipitation to Land Surface Conditions for a 12-Day Warm-Season Convection Period. Mon. Wea. Rev., 136, 2321-2343.

Alfieri, J.G., D. Niyogi, P. Blanken, F. Chen, M.A. LeMone, K. Mitchelle, M.E. Ek, and A. Kumar, 2007: Estimation of the Minimum Canopy Resistance for Croplands and Grasslands Using Data from the 2002 International H2O Project. Mon. Wea. Rev., submitted

LeMone, M.A., M. Tewari, F. Chen, J. Alfieri, and D. Niyogi, 2008: Evaluation of the Noah land-surface model using data from a fair-weather IHOP_200 day with heterogeneous surface fluxes. Mon. Wea. Rev., in press.

Liu, Y., T.T. Warner, J. F. Bowers, L. P. Carson, F. Chen, C. A. Clough, C. A. Davis, C. H. Egeland, S. Halvorson, T.W. Huck Jr., L. Lachapelle, R.E. Malone, D. L. Rife, R.-S. Sheu, S. P. Swerdlin, and D.S. Weingarten, 2008: The operational mesogamma-scale analysis and forecast system of the U.S. Army Test and Evaluation Command. Part 1: Overview of the modeling system, the forecast products. J. of Appl. Meteor. Clim., 47,1077-1093.

Gao, Y., F. Chen, M. Barlage, W. Liu, Y. Ran, H. Li, H. Peng, and M. Ma, 2008: Enhancement of Land Surface Information and its Impact on Atmospheric Modeling in the Heihe River Basin, Northwest China. J. Geophys. Res., in press.

Miao, S., and F. Chen, 2008: Formation of horizontal convective rolls in urban areas. Atm. Res., 89, 298-304.

Lin, C-Y, F. Chen, J.C. Huang, W-C. Chen, Y.-A. Liou, W.-N. Chen and Shaw-C. Liu, 2008: Urban Heat Island effect and its impact on boundary layer development and land-sea circulation over northern Taiwan, Atmospheric Environment. 42, 5635-5649.

Miao, S., F. Chen, M.A. LeMone, M. Tewari, Q. Li, and Y. Wang, 2008: An Observational and Modeling Study of Characteristics of Urban Heat Island and Boundary Layer Structures in Beijing. J. Appl. Meteorol. Clim., in press.

Jiang, X.Y., C. Wiedinmyer, F. Chen, Z.-L. Yang, and J. C. F. Lo, 2008: Predicted Impacts of Climate and Land-Use Change on Surface Ozone in the Houston Area. J. Geophys. Res., in press.

2007

Chen, F., K.W. Manning, M. A. LeMone, S.B. Trier, J.G. Alfieri, R. Roberts, M. Tewari, D. Niyogi, T. W. Horst, S.P. Oncley, J.B. Basara, and P.D. Blanken, 2007: Description and Evaluation of the Characteristics of the NCAR High-Resolution Land Data Assimilation System During IHOP-02. J. Appl. Meteorol. and Climatology, 46, 694-713.

Lo, J.C.F., A.K.H. Lau, F. Chen, J.C.H. Fung, and K.K.M. Leung, 2007: Urban Modification in a Mesoscale Model and the Effects on the Local Circulation in the Pearl River Delta Region. J. Appl. Meteorol. Climatol., 46, 457–476.

Alfieri, J.G., D. Niyogi, M.A. LeMone, F. Chen, and S. Fall, 2007: A simple reclassification method for correcting uncertainty in land use/land cover datasets used with land surface models. Pure and Appl. Geophys., 164 (2007) 1789-1809, 0033-4553/07/091789-21, DOI 10.1007/s00024-007-0241-4

Niyogi, D., H.I Chang, F. Chen, L. Gu, A. Kumar, S. Menon, and R. A. Pielke Sr., 2007: Potential Impacts of Aerosol-Land-Atmosphere Interactions on the Indian Monsoonal Rainfall Characteristics. Natural Hazards- Monsoon special issue. Natural Hazards (Monsoon Special issue), DOI 10.1007/s11069-006-9085-y.

LeMone, M.A., F. Chen, J. Alfieri, R. Cuenca, Y. Hagimoto, P. Blanken, D. Niyogi, S. Kang, K. Davis, and R. Grossman, 2007: NCAR/CU surface, soil, and vegetation observation network during the IHOP_2002 field campaign. Bull. Amer. Meteor. Soc., 88, 65-81. abstract

LeMone, M.A., F. Chen, J.G. Alfieri, M. Tewari, B. Geerts, Q. Miao, R.L. Grossman, and R.L. Coulter, 2007: Influence of land cover, soil moisture, and terrain on the horizontal distribution of sensible and latent heat fluxes and boundary layer structure in southeast Kansas during IHOP_2002 and CASES-97. J. Hydrometeorology, 8, 68-87. abstract

Kiemle, C., G. Ehret, A. Fix, M. Wirth, G. Poberaj, R.M. Hardesty, W. Brewer, C. Senff, and M. LeMone, 2007: Latent Heat Flux Profiles from Collocated Airborne Water Vapor and Wind Lidars during IHOP. J. Atmos. Ocean. Tech., 24, 627–639.

Strassberg, D., M. LeMone, T. Warner, and J. Alfieri, 2007: Comparison of 10-m observed wind speeds to those based on Monin-Obukhov Similarity theory using IHOP_2002 aircraft and surface data. Mon. Wea. Rev., In press.

Kang, S.-L., K.J. Davis, and M.A. LeMone, 2007: Observations of the ABL over a heterogeneous land surface during IHOP_2002. J. Hydrometeorology, 8, 221-244

2006

Lo, J. C. , A. K. H. Lau, Z. B. Yuan, J. C. H. Fung, and F. Chen, 2006 A physical modeling approach for identification of source regions of primary and secondary air pollutants . Atmos. Chem. Phys. Discuss., 6, 6467-6496

Holt, T., D. Niyogi, F. Chen, K. Manning, M. A. LeMone, A. Qureshi, 2006: Effect of Land-Atmosphere Interactions on the IHOP 24-25 May 2002 Convection Case, Mon. Wea. Rev, 134, 113-133 abstract

Liu, Y., F. Chen, T. Warner, and J. Basara, 2006: Verification of a Mesoscale Data-Assimilation and Forecasting System for the Oklahoma City Area During the Joint Urban 2003 Field Project. J. Appl. Meteorol. and Climatology, 45, 912-929. abstract

Lo, J., A. K. H. Lau, J. C. H. Fung, and F, Chen, 2006: Investigation of Enhanced Cross-City Transport and Trapping of Air Pollutants by Coastal and Urban Land-Sea Breeze Circulations. J. Geophy. Res., 111, D14104, doi:10.1029/2005JD006837.abstract

Lo, J. C. , A. K. H. Lau, Z. B. Yuan, J. C. H. Fung, and F. Chen, 2006 A physical modeling approach for identification of source regions of primary and secondary air pollutants . Atmos. Chem. Phys. Discuss., 6, 6467-6496. abstract

Miao, Q., B. Geerts, and M. LeMone, 2006: Vertical velocity and buoyancy characteristics of coherent echo plumes in the convective boundary layer detected by a profiling airborne lidar. J. Appl. Meteor. Climat., 45, 838-855.

2005

Chen, F., 2005: Variability in global land surface energy budgets during 1987-1988 simulated by an offline land surface model. Climate Dynamics, May 2005. doi: 10.1007/s00382-004-0439-4. abstract

Wang, Y., J. Li, F. Chen, D. Lenschow, J. Sun, D. Niyogi, K. Lau, M. Zhou,W. Jiang, G. Ding, J. Chen, and D. Wu, 2005: Challenge and Opportunities in Urban Meteorology Research and Forecast. Science Foundation in China, 13, No.1, 23-30.

2004

Trier, S., F. Chen, and K. Manning, 2004. A Study of convection initiation in a mesoscale model using high-resolution land surface initiation conditions. Mon. Wea. Rev., 132, 2954-2976. abstract

Niyogi D, Chang H, Saxena VK, Holt T, Alapaty K, Booker, F, Chen F, Davis, KJ, Holben B, Matsui T, Meyers T, Oechel WC, Pielke RA, Sr, Wells R, Wilson K, Xue Y, 2004: Direct Observations of the Effects of Aerosol Loading on Net Ecosystem CO2 Exchanges Over Different Landscapes, Geophysical Research Letters, Vol,31, L20506, doi:10.1029/2004GL020915, 2004. abstract

Grossman, R.L., D. Yates, M. LeMone, M.L. Wesely, J. Song, 2004: Observed effects of horizontal surface temperature variations on the atmosphere over a midwest watershed during CASES-97 . J. Geophys. Res., 110, DO6117, doi:10.1029/2004JD004542. abstract

Weckwerth, T.W., D.B. Parsons, S.E. Koch, J.A. Moore, M.A. LeMone, B.B. Demoz, C. Flamant, B. Geerts, J. Wang, and W. Feltz, 2004: An overview of the International H2O Project (IHOP 2002) and some preliminary highlights . Bull. Amer. Meteor. Soc., 85, 253-277. abstract

2003

Chen, F., D. N. Yates, H. Nagai, M. A. LeMone, K. Ikeda, and R. L. Grossman, 2003. Land-Surface Heterogeneity in the Cooperative Atmosphere Surface Exchange Study (CASES-97). Part-I: Comparing Modeled Surface Flux Maps With Surface-Tower and Aircraft Measurements. . J. Hydrometeorol., 4, 196-218. abstract

Yates, D.N., F. Chen, and H. Nagai, 2003. Land-Surface Heterogeneity in the Cooperative Atmosphere Surface Exchange Study (CASES-97). Part-II: Analysis of spatial heterogeneity and their scaling. J. Hydrometeorol., 4, 219-234. abstract

LeMone, M., R. Grossman, F. Chen, K. Ikeda, and D.Yates, 2003. Choosing the averaging interval for comparison of observed and modeled fluxes along aircraft transects over a heterogeneous surface. . J. Hydrometeorol., 4, 179-195. abstract

Sridhar, V., R.L. Elliott, and F. Chen, 2003. Scaling effects on modeled surface energy-balance components using the NOAH- OSU land surface model . J. Hydrology, 280, no 1-4, pp 105-123. abstract

LeMone, M.A., K. Ikeda, R.L. Grossman, and Mathias Rotach, 2003: Horizontal Variability of 2-m temperature at night. CASES-99 Special Issue . J. Atmos. Sci., 60, 2431-2449. abstract

2002

Rife, D.L., T.T. Warner, F. Chen, and E. Astling, 2002. Mechanisms for Diurnal Boundary Layer Circulations in the Great Basin Desert. Mon. Wea. Rev., 130, 921-939. abstract

Sridhar, V., R.L. Elliott, F. Chen, and J.A. Brotzge, 2002. Validation of the NOAH/OSU land surface model using surface flux measurements in Oklahoma. J. Geophys. Res., 107(D20), 4418, doi:10.1029/2001JD001306. abstract

LeMone, M., R. Grossman, R.T. McMillen, K.N. Liou, S. Ou, S. McKeen, W. Angevine, K. Ikeda, and F. Chen, 2002. CASES-97: Late morning warming and moistening of the convective mixed layer over the Walnut River watershed. Boundary Layer Meteorology, 104, 1-52. abstract

2001

Chen, F. and J.Dudhia, 2001: Coupling an Advanced Land Surface-Hydrology Model with the Penn State-NCAR MM5 Modeling System. Part I: Model Implementation and Sensitivity. Mon. Wea. Rev., 129 , 569-585. abstract

Chen, F. and J.Dudhia. 2001. Coupling an Advanced Land Surface-Hydrology Model with the Penn State-NCAR MM5 Modeling System. Part II: Preliminary Model Validation. Mon. Wea. Rev., 129, 587-604. abstract

Chen, F. T. Warner, and K. Manning, 2001. Sensitivity of orographic moist convection to landscape variability: A Study of the Buffalo Creek, Colorado, flash-flood case of 1996. J. Atmos. Sci., 58, 3204-3223. abstract

Yates, D.N., F. Chen, R. Qualls, M. LeMone, and S. Oncley, 2001: A Cooperative Atmosphere-Surface Exchange Study (CASES) Dataset for Analyzing and Parameterizing the Effects of Land Surface Heterogeneity on Area-Averaged Surface Heat Fluxe. J. Appl. Meteorol., 40, 921-937. abstract

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