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DOI	10.5194/tc-14-1809-2020
	The added value of high resolution in estimating the surface mass balance in southern Greenland
	Jan Van De Berg W.; Van Meijgaard E.; Van Ulft L.H.
发表日期	2020
ISSN	19940416
起始页码	1809
结束页码	1827
卷号	14 期号:6
英文摘要	The polar version of the regional climate model RACMO2, version 2.3p1, is used to study the effect of model resolution on the simulated climate and surface mass balance (SMB) of south Greenland for the current climate (2007-2014). The model data at resolutions of 60, 20, 6.6, and 2.2 span classCombining double low line"inline-formula"km/span are intercompared and compared to SMB observations using three different data refinement methods: nearest neighbour, bilinear interpolation, and a statistical downscaling method utilising the local dependency of fields on elevation. Furthermore, it is estimated how the errors induced by model resolution compare to errors induced by the model physics and initialisation./p pThe results affirm earlier studies that SMB components which are tightly linked to elevation, like runoff, can be refined successfully, as soon as the ablation zone is reasonably well resolved in the source dataset. Precipitation fields are also highly elevation dependent, but precipitation has no systematic correlation with elevation, which inhibits statistical downscaling to work well. If refined component-wise, 20 span classCombining double low line"inline-formula"km/span resolution model simulations can reproduce the SMB ablation observations almost as well as the finer-resolution model simulations. Nonetheless, statistical downscaling and regional climate modelling are complementary; the best results are obtained when high-resolution RACMO2 data are statistically refined. Model estimates in the accumulation zone do not benefit from statistical downscaling; hence, a resolution of about 20 span classCombining double low line"inline-formula"km/span is sufficient to resolve the majority of the accumulation zone of the Greenland Ice Sheet with respect to the limited measurements we have./p pFurthermore, we demonstrate that using RACMO2, a hydrostatic model, at 2.2 span classCombining double low line"inline-formula"km/span resolution led to invalid results as topographic and synoptic vertical winds exceed 10 span classCombining double low line"inline-formula"m s-1/span, which violates the hydrostatic model assumptions./p pFinally, additional tests show that model resolution is as important as properly resolving spatial albedo patterns, correctly initialising the firn column, and uncertainties in the modelled precipitation and turbulent exchange. © Author(s) 2020.
英文关键词	climate modeling; estimation method; mass balance; precipitation (climatology); regional climate; Arctic; Arctic Ocean; Greenland; Greenland Ice Sheet; Greenland Sea; Norwegian Sea
语种	英语
来源期刊	Cryosphere
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/202113
作者单位	IMAU, Utrecht University, Utrecht, Netherlands; KNMI, De Bilt, Netherlands
推荐引用方式 GB/T 7714	Jan Van De Berg W.,Van Meijgaard E.,Van Ulft L.H.. The added value of high resolution in estimating the surface mass balance in southern Greenland[J],2020,14(6).
APA	Jan Van De Berg W.,Van Meijgaard E.,&Van Ulft L.H..(2020).The added value of high resolution in estimating the surface mass balance in southern Greenland.Cryosphere,14(6).
MLA	Jan Van De Berg W.,et al."The added value of high resolution in estimating the surface mass balance in southern Greenland".Cryosphere 14.6(2020).