| DOI: | 10.1007/s00382-017-3996-z
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| Scopus记录号: | 2-s2.0-85033475432
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| 论文题名: | Uncertainties in modelling the climate impact of irrigation |
| 作者: | de Vrese P.; Hagemann S.
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| 刊名: | Climate Dynamics
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| ISSN: | 9307575
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| 出版年: | 2018
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| 卷: | 51, 期:2018-05-06 | | 起始页码: | 2023
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| 结束页码: | 2038
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| 语种: | 英语
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| 英文关键词: | Climate impacts
; Irrigation
; Land use
; Uncertainty
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| Scopus关键词: | climate effect
; computer simulation
; irrigation
; land use
; numerical model
; seasonality
; uncertainty analysis
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| 英文摘要: | Irrigation-based agriculture constitutes an essential factor for food security as well as fresh water resources and has a distinct impact on regional and global climate. Many issues related to irrigation’s climate impact are addressed in studies that apply a wide range of models. These involve substantial uncertainties related to differences in the model’s structure and its parametrizations on the one hand and the need for simplifying assumptions for the representation of irrigation on the other hand. To address these uncertainties, we used the Max Planck Institute for Meteorology’s Earth System model into which a simple irrigation scheme was implemented. In order to estimate possible uncertainties with regard to the model’s more general structure, we compared the climate impact of irrigation between three simulations that use different schemes for the land-surface–atmosphere coupling. Here, it can be shown that the choice of coupling scheme does not only affect the magnitude of possible impacts but even their direction. For example, when using a scheme that does not explicitly resolve spatial subgrid scale heterogeneity at the surface, irrigation reduces the atmospheric water content, even in heavily irrigated regions. Contrarily, in simulations that use a coupling scheme that resolves heterogeneity at the surface or even within the lowest layers of the atmosphere, irrigation increases the average atmospheric specific humidity. A second experiment targeted possible uncertainties related to the representation of irrigation characteristics. Here, in four simulations the irrigation effectiveness (controlled by the target soil moisture and the non-vegetated fraction of the grid box that receives irrigation) and the timing of delivery were varied. The second experiment shows that uncertainties related to the modelled irrigation characteristics, especially the irrigation effectiveness, are also substantial. In general the impact of irrigation on the state of the land surface is more than three times larger when assuming a low irrigation effectiveness than when a high effectiveness is assumed. For certain variables, such as the vertically integrated water vapour, the impact is almost an order of magnitude larger. The timing of irrigation also has non-negligible effects on the simulated climate impacts and it can strongly alter their seasonality. © 2018, The Author(s). |
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| 资源类型: | 期刊论文
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| 标识符: | http://119.78.100.158/handle/2HF3EXSE/109149
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| Appears in Collections: | 影响、适应和脆弱性
气候变化事实与影响
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作者单位: | Max Planck Institute for Meteorology, Bundesstrae 53, Hamburg, 20146, Germany; Helmholtz-Zentrum Geesthacht, Max-Planck-Straße 1, Geesthacht, 21502, Germany
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| Recommended Citation: | |
de Vrese P.,Hagemann S.. Uncertainties in modelling the climate impact of irrigation[J]. Climate Dynamics,2018-01-01,51(2018-05-06)
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