Dynamical Global Downscaling of Global Reanalysis
Dynamical Global Downscaling of Global Reanalysis
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DOI：
10.1175/2008mwr2281.1
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发表时间：
2008-08
影响因子：
3.2
通讯作者：
K. Yoshimura;M. Kanamitsu
中科院分区：
文献类型：
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作者：
K. Yoshimura;M. Kanamitsu
摘要为了从粗分辨率再分析中获得更高分辨率的全球再分析数据集，本文提出了一种基于全球谱模式的全球动力学降尺度方法。一个变种的光谱nudging，修改后的形式的尺度选择偏差修正区域模式。该方法包括：（1）除了风的纬向和纬向分量外，还包括温度的轻推;（2）轻推扰动场而不是扰动趋势;（3）没有轻推和湿度校正。在2001年期间，在所谓的R-2再分析（T62 L28分辨率，或约200公里分辨率）的驱动下，使用T248 L28（约50公里分辨率）全球模式进行了缩小尺度的实验。高分辨率观测结果表明，全球月平均地表温度和降水日变化都有很大改善。在北美，地面风速和温度要好得多，在日本，diu...
Abstract With the aim of producing higher-resolution global reanalysis datasets from coarse-resolution reanalysis, a global version of the dynamical downscaling using a global spectral model is developed. A variant of spectral nudging, the modified form of scale-selective bias correction developed for regional models is adopted. The method includes 1) nudging of temperature in addition to the zonal and meridional components of winds, 2) nudging to the perturbation field rather than to the perturbation tendency, and 3) no nudging and correction of the humidity. The downscaling experiment was performed using a T248L28 (about 50-km resolution) global model, driven by the so-called R-2 reanalysis (T62L28 resolution, or about 200-km resolution) during 2001. Evaluation with high-resolution observations showed that the monthly averaged global surface temperature and daily variation of precipitation were much improved. Over North America, surface wind speed and temperature are much better, and over Japan, the diu...