Sensitivity of Near-Surface Temperature Forecasts to Soil Properties over a Sparsely Vegetated Dryland Region
Sensitivity of Near-Surface Temperature Forecasts to Soil Properties over a Sparsely Vegetated Dryland Region
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DOI：
10.1175/jamc-d-13-0362.1
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发表时间：
2014-08
影响因子：
3
通讯作者：
Jeffrey;-D.;Massey;-W.;James W. Steenburgh;Sebastián;HoCH
中科院分区：
文献类型：
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作者：
Jeffrey;-D.;Massey;-W.;James W. Steenburgh;Sebastián;HoCH
[摘要]大盐湖沙漠天气研究与预报模式对犹他州北部Dugway试验场植被稀疏的粉壤土区夜间降温的预报存在误差，凌晨2 m AGL温度平均正偏差为3.4°C [1200 UTC (0500 LST)]。邻近的砂壤土区也存在正的清晨偏差。这些偏差与粉壤土和砂壤土中土壤水分初始化和土壤导热系数参数化不当有关。通过用观测到的土壤湿度初始化，以及用McCumber和Pielke在1981年提出的粉壤土和砂壤土的参数化取代Johansen 1975年在Noah陆面模型中提出的土壤热导率参数化，可以改善2米温度的预报。案例研究表明，这种变化可以显著减少粉壤土和砂壤土在2米温度下的夜间温暖偏差，对土壤的影响最大。
AbstractWeather Research and Forecasting Model forecasts over the Great Salt Lake Desert erroneously underpredict nocturnal cooling over the sparsely vegetated silt loam soil area of Dugway Proving Ground in northern Utah, with a mean positive bias error in temperature at 2 m AGL of 3.4°C in the early morning [1200 UTC (0500 LST)]. Positive early-morning bias errors also exist in nearby sandy loam soil areas. These biases are related to the improper initialization of soil moisture and parameterization of soil thermal conductivity in silt loam and sandy loam soils. Forecasts of 2-m temperature can be improved by initializing with observed soil moisture and by replacing Johansen's 1975 parameterization of soil thermal conductivity in the Noah land surface model with that proposed by McCumber and Pielke in 1981 for silt loam and sandy loam soils. Case studies illustrate that this change can dramatically reduce nighttime warm biases in 2-m temperature over silt loam and sandy loam soils, with the greatest imp...