title: Spatial and temporal evolution of climatic factors and its impacts on potential evapotranspiration in Loess Plateau of Northern Shaanxi, China.
abstract: Agriculture is very sensitive to climate change, and correct forecasting of climate change is a great help to accurate allocation of irrigation water. The use of irrigation water is influenced by crop water demand and precipitation. Potential evapotranspiration (ET0) is a measure of the ability of the atmosphere to remove water from the surface through the processes of evaporation and transpiration, assuming no control on water supply. It plays an important role in assessing crop water requirements, regional dry-wet conditions, and other factors of water resource management. This study analyzed the spatial and temporal evolution processes and characteristics of major meteorological parameters at 10 stations in the Loess Plateau of northern Shaanxi (LPNS). By using the Mann-Kendall trend test with trend-free pre-whitening and the ArcGIS platform, the potential evapotranspiration of each station was quantified by using the Penman-Monteith equation, and the effects of climatic factors on potential evapotranspiration were assessed by analyzing the contribution rate and sensitivity of the climatic factors. The results showed that the climate in LPNS has become warmer and drier. In terms of the sensitivity of ET0to the variation of each climatic factor in LPNS, relative humidity (0.65) had the highest sensitivity, followed by daily maximum temperature, wind speed, sunshine hours, and daily minimum temperature (-0.05). In terms of the contribution rate of each factor to ET0, daily maximum temperature (5.16%) had the highest value, followed by daily minimum temperature, sunshine hours, relative humidity, and wind speed (1.14%). This study provides a reference for the management of agricultural water resources and for countermeasures to climate change. According to the climate change and the characteristics of the study area, farmers in the region should increase irrigation to guarantee crop water demand.
authors.affiliation: College of Water Resources and Architectural Engineering, Northwest A&F University, Yangling, 712100, China; Key Laboratory of Agricultural Soil and Water Engineering in Arid and Semiarid Areas, Ministry of Education, Northwest A&F University, Yangling 712100, Shaanxi, China.
authors.forename: C
authors.initials: C
authors.lastname: Li
authors.affiliation: Key Laboratory of Agricultural Soil and Water Engineering in Arid and Semiarid Areas, Ministry of Education, Northwest A&F University, Yangling 712100, Shaanxi, China; Institute of Water Saving Agriculture in Arid regions of China, Northwest A&F University, Yangling 712100, Shaanxi, China. Electronic address: gjzwpt@vip.sina.com.
authors.forename: P T
authors.initials: PT
authors.lastname: Wu
authors.affiliation: Institute of Water Saving Agriculture in Arid regions of China, Northwest A&F University, Yangling 712100, Shaanxi, China; Institute of Soil and Water Conservation, Northwest A&F University, Yangling 712100, China.
authors.forename: X L
authors.initials: XL
authors.lastname: Li
authors.affiliation: Institute of Water Saving Agriculture in Arid regions of China, Northwest A&F University, Yangling 712100, Shaanxi, China; Institute of Soil and Water Conservation, Northwest A&F University, Yangling 712100, China.
authors.forename: T W
authors.initials: TW
authors.lastname: Zhou
authors.affiliation: College of Water Resources and Architectural Engineering, Northwest A&F University, Yangling, 712100, China; Key Laboratory of Agricultural Soil and Water Engineering in Arid and Semiarid Areas, Ministry of Education, Northwest A&F University, Yangling 712100, Shaanxi, China; Institute of Water Saving Agriculture in Arid regions of China, Northwest A&F University, Yangling 712100, Shaanxi, China. Electronic address: sksun@nwafu.edu.cn.
authors.forename: S K
authors.initials: SK
authors.lastname: Sun
authors.affiliation: College of Water Resources and Architectural Engineering, Northwest A&F University, Yangling, 712100, China; Key Laboratory of Agricultural Soil and Water Engineering in Arid and Semiarid Areas, Ministry of Education, Northwest A&F University, Yangling 712100, Shaanxi, China; Institute of Water Saving Agriculture in Arid regions of China, Northwest A&F University, Yangling 712100, Shaanxi, China.
authors.forename: Y B
authors.initials: YB
authors.lastname: Wang
authors.affiliation: Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resources, Yangling 712100, China.
authors.forename: X B
authors.initials: XB
authors.lastname: Luan
authors.affiliation: College of Water Resources and Architectural Engineering, Northwest A&F University, Yangling, 712100, China.
authors.forename: X
authors.initials: X
authors.lastname: Yu
keywords: Climatic factors; Loess Plateau; Potential evapotranspiration; Sensitivity analysis; Spatial and temporal evolution