基于CMIP6气候情景的泾河流域水文模拟及预测

Hydrological simulation and prediction of the Jinghe River Basin based on CMIP6 climate scenario

摘要

【目的】气候变化和人类活动引发的土地利用变化为水资源调控与管理带来了挑战,使得探究在两者影响下的水文模拟过程并进行定量预测和分析成为了目前的研究需要。【方法】基于CMIP6的3种气候模式ACCESS-CM2、BCC-CSM2-MR、Nor ESM2-LM的两种浓度情景SSP245、SSP585,通过偏差订正后模拟出泾河流域在未来时期(2022—2044年)的降水、最低气温和最高气温;基于2005年和2015年流域土地利用数据,利用CA-markov模型预测流域2025年土地利用空间分布,并结合气候模式数据,驱动SWAT分布式水文模型,预测泾河流域未来时期的径流变化,并分析两种因素对径流变化率的影响。【结果】研究结果表明:(1)未来时期(2022—2044年)SSP245和SSP585情景下,年平均降水相对于基准期(2006—2012年)分别上升0.3%和1.41%,最低气温分别上升0.9℃和1.11℃,最高气温分别上升0.28℃和0.07℃。(2)2025年建设用地和耕地面积相较于2005年分别增加了34.97%和3.15%,而草地和林地面积减少了4.30%和1.59%。(3)基准期径流模拟值与实测值在率定期和验证期的R²和NSE值分别为0.86和0.7、0.76和0.71, R²均大于0.7, NSE均大于0.65。(4)S45_LUC05、S85_LUC05、S45_LUC25、S85_LUC25四种情景年平均径流模拟值分别为387 m³/s,387.87 m³/s、419.17 m³/s、422.94 m³/s。【结论】(1)未来时期(2022—2044年)泾河流域年均降水和年均气温呈整体上升趋势。(2)未来时期(2025年)泾河流域建设用地面积将显著增加,草地和林地面积呈减少趋势。(3)SWAT模型在泾河流域水文模拟中适用性较好。(4)4种情景驱动下未来径流呈上升趋势,气候与土地利用变化共同影响了径流变化,土地利用变化对径流影响程度大于气候因素。

Abstract

[Purpose]The land use change caused by climate change and human activities brings challenges to water resources regulation and management, which makes it a current research need to explore the hydrological simulation process under the influence of both and make quantitative prediction and analysis. [Methods] Based on three climate models of CMIP6, namely ACCESS-CM2, BCC-CSM2-MR, and Nor ESM2-LM, two concentration scenarios SSP245 and SSP585 were used to simulate the precipitation, minimum temperature, and maximum temperature of the Jinghe River Basin in the future period(2022—2044)after deviation correction; Based on the land use data of the watershed in 2005 and 2015, the CA-Markov model is used to predict the spatial distribution of land use in the watershed in 2025. Combined with climate model data, the SWAT distributed hydrological model is driven to predict future runoff changes in the Jinghe River Basin and analyze the impact of two factors on the rate of runoff change. [Results] The research result indicate that:(1) In the future period(2022—2044), under the SSP245 and SSP585 scenarios, the annual average precipitation will increase by 0. 3% and 1. 41% compared to the reference period(2006—2012), with the lowest temperature increasing by 0. 9 ℃ and 1. 11 ℃, and the highest temperature increasing by 0. 28 ℃ and 0. 07 ℃, respectively.(2) In 2025, the area of construction land and arable land increased by 34. 97% and 3. 15% respectively compared to 2005, while the area of grassland and forest land decreased by 4. 30% and 1. 59%.(3) The R² and NSE values of the simulated and measured runoff values during the reference period and validation period are 0. 86 and 0. 7,0. 76 and 0. 71, respectively, with R² greater than 0. 7 and NSE greater than 0. 65.(4) The simulated annual average runoff values for the four scenarios(S45_ LUC05, S85_ LUC05, S45_ LUC25, S85_LUC25) are 387 m³/s, 387. 87 m³/s, 419. 17 m³/s, and 422. 94 m³/s, respectively. [Conclusion] (1) In the future(2022—2044), the average annual precipitation and temperature in the Jinghe River Basin will show an overall upward trend.(2) In the future period(2025), the construction land area of the Jinghe River Basin will significantly increase, while the grassland and forest area will show a decreasing trend.(3) The SWAT model has good applicability in hydrological simulation of the Jinghe River Basin.(4) Under the four scenarios, future runoff will show an upward trend, Climate and land use change jointly affect runoff change, and the impact of land use change on runoff is greater than that of climate factors.

关键词

CMIP6 / SWAT模型 / 土地利用 / 径流模拟 / 泾河流域 / 气候变化 / 降水

Key words

CMIP6 / SWAT model / land use / runoff simulation / Jinghe River Basin / climate change / precipitation

基金资助

国家自然科学基金项目(41471452)

陕西省自然科学基金项目(2021JM-161)

陕西省自然科学基金项目(2020ZDLSF06-07)

中央高校基本科研业务资助项目(300102269201)

中央高校基本科研业务资助项目(300102299206)