Atmospheric and Oceanographic Sciences Library, 2011
>When the first satellite imagery became available, they evidenced human impacts on land-cover... more >When the first satellite imagery became available, they evidenced human impacts on land-cover on a large scale. They showed cities, deforestation pattern, international borders, and even land-cover changes (LCC) and their impacts from space (Fig. 3.1). The Negev, for instance, appears much darker than the Sinai where grazing is unrestricted (Nicholson et al.
0.175, 0.225, 0.275, 0.325, 0.375, 0.425, 0.475, 0.525, 0.575, 0.625, 0.675, 0.725, 0.775, 0.825,... more 0.175, 0.225, 0.275, 0.325, 0.375, 0.425, 0.475, 0.525, 0.575, 0.625, 0.675, 0.725, 0.775, 0.825, 0.87, 0.91, 0.945, 0.97, 0.985, 0.995 reaching to 100 hPa. c. Vegetation fraction, soil and land-use data The vegetation fraction, soil and land use data, field capacity as well as permanent wilting point are assigned as described by Chen and Dudhia (2000).
The soil module of the Hydro–Thermodynamic Soil–Vegetation Scheme is evaluated by soil temperatur... more The soil module of the Hydro–Thermodynamic Soil–Vegetation Scheme is evaluated by soil temperature observations and independent theoretical numerical results. To gain the latter, a Galerkin weak finite-element (GWFE) scheme is implemented for solving the heat and water balance equations that are originally solved by a Crank–Nicholson finite-difference (CNFD) scheme. The GWFE scheme captures discontinuities well and has a high phase fidelity. When/where frozen ground thaws and under moderate advection-dominated regimes, peak temperatures simulated with the CNFD scheme are up to seven days off compared with observations and the results of the GWFE scheme. If freeze–thaw cycles repeat for more than a month, CNFD predictions will oscillate ±1 K around the observations but will converge to the observations and results of the GWFE scheme afterward. Under diffusion-dominated regimes, CNFD runs perform well with similar quality to the GWFE predictions. Comparisons of the results of both num...
The Hydro–Thermodynamic Soil–Vegetation Scheme (HTSVS) coupled in a two-way mode with the fifth-g... more The Hydro–Thermodynamic Soil–Vegetation Scheme (HTSVS) coupled in a two-way mode with the fifth-generation Pennsylvania State University–National Center for Atmospheric Research (NCAR) Mesoscale Meteorological Model (MM5) is evaluated for a typical snowmelt episode in the Baltic region by means of observations at 25 soil temperature, 355 snow-depth, and 344 precipitation sites that have, in total, 1000, 1775, and 1720 measurements, respectively. The performance with respect to predicted near-surface meteorological fields is evaluated using reanalysis data. Snow depth depends on snow metamorphism, sublimation, and snowfall. Because in the coupled model these processes are affected by the predicted surface radiation fluxes and cloud and precipitation processes, sensitivity studies are performed with two different cloud microphysical schemes and/or radiation schemes. Skill scores are calculated as a quality measure for the coupled model’s performance for a typical forecast range of 120...
Atmospheric and Oceanographic Sciences Library, 2011
>When the first satellite imagery became available, they evidenced human impacts on land-cover... more >When the first satellite imagery became available, they evidenced human impacts on land-cover on a large scale. They showed cities, deforestation pattern, international borders, and even land-cover changes (LCC) and their impacts from space (Fig. 3.1). The Negev, for instance, appears much darker than the Sinai where grazing is unrestricted (Nicholson et al.
0.175, 0.225, 0.275, 0.325, 0.375, 0.425, 0.475, 0.525, 0.575, 0.625, 0.675, 0.725, 0.775, 0.825,... more 0.175, 0.225, 0.275, 0.325, 0.375, 0.425, 0.475, 0.525, 0.575, 0.625, 0.675, 0.725, 0.775, 0.825, 0.87, 0.91, 0.945, 0.97, 0.985, 0.995 reaching to 100 hPa. c. Vegetation fraction, soil and land-use data The vegetation fraction, soil and land use data, field capacity as well as permanent wilting point are assigned as described by Chen and Dudhia (2000).
The soil module of the Hydro–Thermodynamic Soil–Vegetation Scheme is evaluated by soil temperatur... more The soil module of the Hydro–Thermodynamic Soil–Vegetation Scheme is evaluated by soil temperature observations and independent theoretical numerical results. To gain the latter, a Galerkin weak finite-element (GWFE) scheme is implemented for solving the heat and water balance equations that are originally solved by a Crank–Nicholson finite-difference (CNFD) scheme. The GWFE scheme captures discontinuities well and has a high phase fidelity. When/where frozen ground thaws and under moderate advection-dominated regimes, peak temperatures simulated with the CNFD scheme are up to seven days off compared with observations and the results of the GWFE scheme. If freeze–thaw cycles repeat for more than a month, CNFD predictions will oscillate ±1 K around the observations but will converge to the observations and results of the GWFE scheme afterward. Under diffusion-dominated regimes, CNFD runs perform well with similar quality to the GWFE predictions. Comparisons of the results of both num...
The Hydro–Thermodynamic Soil–Vegetation Scheme (HTSVS) coupled in a two-way mode with the fifth-g... more The Hydro–Thermodynamic Soil–Vegetation Scheme (HTSVS) coupled in a two-way mode with the fifth-generation Pennsylvania State University–National Center for Atmospheric Research (NCAR) Mesoscale Meteorological Model (MM5) is evaluated for a typical snowmelt episode in the Baltic region by means of observations at 25 soil temperature, 355 snow-depth, and 344 precipitation sites that have, in total, 1000, 1775, and 1720 measurements, respectively. The performance with respect to predicted near-surface meteorological fields is evaluated using reanalysis data. Snow depth depends on snow metamorphism, sublimation, and snowfall. Because in the coupled model these processes are affected by the predicted surface radiation fluxes and cloud and precipitation processes, sensitivity studies are performed with two different cloud microphysical schemes and/or radiation schemes. Skill scores are calculated as a quality measure for the coupled model’s performance for a typical forecast range of 120...
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