Construction of Basin Scale Climate Change Scenarios by theTransfer Function and Stochastic Weather Generation Models

摘要

From the General Circulation Models(GCMs), it is known that the increases ofrnconcentrations of greenhouse gases will have significant implications for climate change inrnglobal and regional scales. The GCM has an uncertainty in analyzing the meteorologicrnprocesses at individual sites and so the "downscaling" techniques are used to bridge thernspatial and temporal resolution gaps between what, at present, climate modellers can providernand what impact assessors require. This paper describes a method for assessing local climaternchange impacts using a statistical downscaling technique. The method facilitates the rapidrndevelopment of multiple, low-cost, single-site scenarios of daily surface weather variablesrnunder current and future regional climate forcing. The construction of climate changernscenarios based on spatial regression(transfer function) downscaling and on the use of a localrnstochastic weather generator is described. Regression downscaling translates the GCM gridboxrnpredictions with coarse resolution of climate change to site-specific values and the valuesrnwere then used to perturb the parameters of the stochastic weather generator in order tornsimulate site-specific daily weather values. In this study, the global climate change scenariosrnare constructed using the YONU GCM control run and transient experiments