Author’s response letter for “Sensitivity of future Continental United States water deficit projections to General Circulation Model, evapotranspiration estimation method, and greenhouse gas emission scenario” by S. Chang et al.

Using a key station approach, statistical downscaling of monthly general circulation model outputs to monthly precipitation, evaporation, minimum temperature and maximum temperature at 17 observation stations located in Victoria, Australia was performed. Using the observations of each predictand, over the period 1950–2010, correlations among all stations were computed. For each predictand, the station which showed the highest number of correlations above 0.80 with other stations was selected as the first key station. The stations that were highly correlated with that key station were considered as the member stations of the first cluster. By employing this same procedure on the remaining stations, the next key station was found. This procedure was performed until all stations were segregated into clusters. Thereafter, using the observations of each predictand, regression equations (inter-station regression relationships) were developed between the key stations and the member stations for each calendar month. The downscaling models at the key stations were developed using reanalysis data as inputs to them. The outputs of HadCM3 pertaining to A2 emission scenario were introduced to these downscaling models to produce projections of the predictands over the period 2000–2099. Then the outputs of these downscaling models were introduced to the inter-station regression relationships to produce projections of predictands at all member stations.

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General Circulation Model Scenarios for the Southern United States

Ecological Studies - The Productivity and Sustainability of Southern Forest Ecosystems in a Changing Environment ◽

10.1007/978-1-4612-2178-4_2 ◽

1998 ◽

pp. 15-54 ◽

Cited By ~ 3

Author(s):

Ellen J. Cooter

Keyword(s):

United States ◽

General Circulation Model ◽

General Circulation ◽

Circulation Model ◽

Southern United States ◽

Model Scenarios

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Air, Sea, and Land Interactions of the Continental U.S. Hydroclimate

Journal of Hydrometeorology ◽

10.1175/2008jhm1003.1 ◽

2009 ◽

Vol 10 (2) ◽

pp. 353-373 ◽

Cited By ~ 9

Author(s):

Vasubandhu Misra ◽

P. A. Dirmeyer

Keyword(s):

United States ◽

General Circulation Model ◽

General Circulation ◽

Winter Season ◽

Circulation Model ◽

Moisture Flux ◽

Boreal Summer ◽

Boreal Winter ◽

Moisture Flux Convergence ◽

The Mean

Abstract Multidecadal simulations over the continental United States by an atmospheric general circulation model coupled to an ocean general circulation model is compared with that forced by observed sea surface temperature (SST). The differences in the mean and the variability of precipitation are found to be larger in the boreal summer than in the winter. This is because the mean SST differences in the two simulations are qualitatively comparable between the two seasons. The analysis shows that, in the boreal summer season, differences in moisture flux convergence resulting from changes in the circulation between the two simulations initiate and sustain changes in precipitation between them. This difference in precipitation is, however, further augmented by the contributions from land surface evaporation, resulting in larger differences of precipitation between the two simulations. However, in the boreal winter season, despite differences in the moisture flux convergence between the two model integrations, the precipitation differences over the continental United States are insignificant. It is also shown that land–atmosphere feedback is comparatively much weaker in the boreal winter season.

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