DOI: 10.1007/s00382-014-2322-2
Scopus记录号: 2-s2.0-84925511511
论文题名: Resolution dependence in simulating the African hydroclimate with the HadGEM3-RA regional climate model
作者: Moufouma-Okia W. ; Jones R.
刊名: Climate Dynamics
ISSN: 9307575
出版年: 2014
卷: 44, 期: 2017-03-04 起始页码: 609
结束页码: 632
语种: 英语
英文关键词: African climate
; CORDEX
; General circulation model
; Horizontal resolution
; Precipitation
; Regional climate modelling
英文摘要: This study documents the effect of horizontal resolution on the ability of the Met Office third-generation Global Atmosphere Regional Climate Model (HadGEM3-RA), a regional atmospheric configuration of the HadGEM3 model, to simulate rainfall variability over Africa. It is based on six 20-year long RCM simulations driven by ERA-Interim reanalysis and performed at 12, 25, 50, 70, 90, and 150 km over the CORDEX-Africa domain. To gain further insight into model errors, we also compared the HadGEM3-RA’s performance to that of the parent General Circulation Model using three different spatial resolutions (70, 100, and 150 km), and to HadRM3P—the current Met Office regional climate model. It is found that the 50 km resolution RCM reproduces reasonably the spatial and temporal features of rainfall variability across regions. These include the seasonal progression of the tropical rainbelt, its extent and location, the annual cycle and interannual variability. Although model biases vary across seasons and locations, a prominent feature is the over-prediction of rainfall totals over Central Africa, and underestimation of rainfall in coastal areas of the Guinea Gulf during boreal spring and autumn. HadGEM3-RA improves with increased horizontal resolution, but some model errors persist. Comparison with the parent global model simulations demonstrates generally a realistic and consistent behaviour over large scales—suggesting that the physical formulation is able to capture the key driving processes, but also confirms the benefit of increasing the model horizontal resolution. Despite the model errors, HadGEM3-RA rainfall shows superiority over that from HadRM3P, ERA-Interim and MERRA datasets—indicating that the associated dynamical features of HadGEM3-RA can complement the physical understanding gained from reanalyses. This article also highlights the challenges for evaluating climate models in data sparse regions where satellite derived rainfall and gridded observational datasets often diverge. © 2014, Crown Copyright.
资助项目: DFID, Department for International Development, UK Government
Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/54560
Appears in Collections: 过去全球变化的重建
There are no files associated with this item.
作者单位: FitzRoy Road, Exeter, United Kingdom; African Climate Policy Centre (ACPC) of the United Nations Economic Commission for Africa (UNECA), Exeter, United Kingdom; African Climate Policy Centre (ACPC), Special Initiative Division, United Nations Economic Commission for Africa (UNECA), P.O. Box 3001, Addis Ababa, Ethiopia
Recommended Citation:
Moufouma-Okia W.,Jones R.. Resolution dependence in simulating the African hydroclimate with the HadGEM3-RA regional climate model[J]. Climate Dynamics,2014-01-01,44(2017-03-04)