Central Taiwan's hydroclimate in response to land use/cover change

• Published in: Environmental research letters Vol. 15; no. 3; pp. 34015 - 34024
• Main Authors: Chen, Chia-Jeng, Chen, Chu-Chun, Lo, Min-Hui, Juang, Jehn-Yih, Chang, Che-Min
• Format: Journal Article
• Language: English
• Published: Bristol IOP Publishing 01.03.2020
• Subjects: Assessments; climate change; Enthalpy; Heat flux; Heat transfer; Hydroclimate; Hydroclimatology; Hydrologic data; Land cover; Land use; land-atmosphere interactions; land-surface model; Landsat; Landsat satellites; Latent heat; Mathematical models; Precipitation; Rainfall; Remote sensing; Sensible heat; Simulation; Specific humidity; Statistical analysis; Urbanization; Weather forecasting; Wind; Taiwan
• ISSN: 1748-9326; 1748-9326
• DOI: 10.1088/1748-9326/ab68aa

Land use/cover change (LUCC) has taken place since the 1990s in central Taiwan; however, its impacts on the local and regional hydroclimatology are not understood thoroughly. This study is grounded in a numerical experiment using the Weather Research and Forecasting (WRF) model and statistical assessments of continuous land cover and gridded precipitation data derived for central Taiwan. We incorporate survey-based land use data in 1995 and 2007 in driving WRF to simulate selective non-rainy and rainy (dry and wet) cases under weak synoptic forcings in July and August (JA). The two land-use conditions reveal changes in simulation fields on account of increased urban and built-up lands. Results averaged over the dry cases show increased (diminished) sensible heat fluxes and 2 m temperatures (latent heat fluxes and 2 m specific humidity) in 2007 compared to that in 1995. The wet-case simulation further identifies intensified precipitation over the downwind areas of urban and built-up lands, strongly subject to local topography and prevailing winds. Statistical assessments of the Landsat land cover and gridded precipitation data verify significant increasing trends in urbanization and the JA rainfall. Regression-based analysis that scales the effect of the LUCC on the change in precipitation corroborates the WRF simulation: LUCC has induced eastward, downwind association with the JA rainfall.