Index Catalog // ScholarsArchive@OSU

Creator:: Mahrt, Larry, Sun, Jielun, MacPherson, J. I., Jensen, N. O., and Desjardins, R. L.
Abstract:: The aerodynamic temperature is required for prediction of the surface heat flux using Monin-Obukhov similarity. This "fictitious" temperature is not systematically equal to the actual air temperature near the surface and is not directly available from observations or in numerical models. The aerodynamic temperature is normally replaced with either the...
Resource Type:: Article

Creator:: Mahrt, Larry, Vickers, Dean, Howell, Jim, Hojstrup, Jorgen, Wilczak, James M., Edson, Jim, and Hare, Jeffrey
Abstract:: This study examines the dependence of the computed drag coefficient on wind speed, stability, fetch, flux sampling problems, and method of calculation of the drag coefficient. The analysis is applied to data collected at a tower 2 km off the coast of Denmark during the Risø Air Sea Experiment (RASEX)....
Resource Type:: Article

Creator:: Gerz, Thomas, Howell, Jim, and Mahrt, Larry
Abstract:: This study addresses the relationship between thermal microfronts and coherent vortex structures in homogeneous turbulence. The turbulence is created by mean shear in a weakly stratified flow. The data set is generated by direct numerical simulation providing highly resolved instantaneous three‐dimensional fields of fluctuating velocity and temperature (1603 data points...
Resource Type:: Article

Creator:: Vickers, Dean and Mahrt, Larry
Abstract:: Vertical profiles of the time-averaged wind stress, wind speed and buoyancy flux from the off-shore tower site in the Risø Air Sea Experiment are used to evaluate similarity theory in the coastal zone. The observed dependence of the non-dimensional wind shear on stability is compared to the traditional parametrization. Relationships...
Resource Type:: Article

Creator:: Mahrt, Larry and Sun, Jielun
Abstract:: The value of the effective exchange coefficient for area-averaged fluxes can depend significantly on the averaging scale. This dependence implies that the exchange coefficient in numerical models should depend on grid size. The main goal of this study is the assessment of the importance of such scale-dependence. When the large-scale...
Resource Type:: Article

Creator:: Mahrt, Larry, Lenschow, D. H., Sun, Jielun, Weil, J. C., MacPherson, J. I., and Desjardins, R. L.
Abstract:: This study examines the spatial variability of ozone fluxes over flat heterogeneous terrain consisting of a patchwork of irrigated and nonirrigated surfaces. Fluxes of ozone and other quantities are computed from eight sequential flight legs of the Canadian Twin Otter research aircraft over the same track at 33 m above...
Resource Type:: Article

Creator:: Mahrt, Larry, Kotwica, K., Sun, Jielun, MacPherson, J.I., and Desjardins, R.L.
Abstract:: Toward the goal of predicting area-averaged evapotranspiration, the evaporative fraction is modelled in terms of surface radiation temperature, air temperature, solar zenith angle, Normalized Difference of the Vegetation Index and albedo. Previous relationships break down when applied simultaneously to a variety of surfaces. The zenith angle is required to account...
Resource Type:: Article

Creator:: Sun, Jielun, Lenschow, Donald H., Mahrt, Larry, Crawford, Tim L., Davis, Kenneth J., Oncley, Steve P., MacPherson, J.I., Wang, Qing, Dobosy, Ron J., and Desjardins, R.L.
Abstract:: Lake-induced atmospheric circulations over three lakes ranging from 3 to 10 km width are analyzed using data from three aircraft during the 1994 Boreal Ecosystem-Atmosphere Study (BOREAS). A well-defined divergent lake breeze circulation is observed over all three lakes during the day. Under light wind conditions, the lake breeze is...
Resource Type:: Article

Creator:: Cuenca, Richard H., Ek, Michael, and Mahrt, Larry
Abstract:: Both the form of functional relationships applied for soil water properties and the natural field-scale variability of such properties can significantly impact simulation of the soil-plant-atmosphere system on a diurnal timescale. Various input parameters for soil water properties including effective saturation, residual water content, anerobiosis point, field capacity, and permanent...
Resource Type:: Article

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