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Paul A. Dirmeyer, Yan Jin, Bohar Singh, and Xiaoqin Yan

of the land surface onto the atmosphere during summer (e.g., Koster et al. 2004 ; Findell et al. 2011 ). Guo et al. (2011) showed that potential predictability from soil moisture is high over North America. North America also demonstrates the strongest improvement in prediction skill from the realistic initialization of the land surface for seasonal forecasts ( Koster et al. 2011 ). The location of maximum land–atmosphere coupling can vary in space ( Koster et al. 2011 ), and its strength can

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Suzana J. Camargo

, these models are able to capture interannual variability associated with El Niño–Southern Oscillation (ENSO) and have been used successfully to develop dynamical ( Vitart and Stockdale 2001 ; Camargo and Barnston 2009 ) and statistical–dynamical ( Wang et al. 2009 ) seasonal forecasts of TC activity. More recently, multiyear hurricane forecasts have been developed using these models ( Smith et al. 2010 ; Vecchi et al. 2013 ). In the last few years, many centers have started to use high

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Kerrie L. Geil, Yolande L. Serra, and Xubin Zeng

and found that the model's enhanced representation of the surface boundary produced an acceptable diurnal cycle of summer precipitation in the monsoon region that was not captured by the driving reanalysis. A recent study by the same group using the Weather Research and Forecasting Model (WRF; Castro et al. 2012 ) showed the potential for limited-area models to improve seasonal NAMS forecasts. The use of higher resolution limited-area models that are able to capture the diurnal cycle of

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Xianan Jiang, Eric D. Maloney, Jui-Lin F. Li, and Duane E. Waliser

results indicate that the variance of ENP ISV tends to be underestimated in most of the CMIP3 GCMs. Meanwhile, the eastward propagation associated with observed ENP ISV is also poorly represented in these CMIP3 models. By applying an extended empirical orthogonal function (EEOF) technique, a recent analysis including many CMIP3-era models illustrated that, among the total of nine models examined, only two GCMs were able to realistically simulate both of the two observed leading ISV modes over the ENP

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Baird Langenbrunner and J. David Neelin

, including the eastern tropical Pacific, the “horseshoe” region in the western tropical Pacific, a southern section of North America, and equatorial South America. Teleconnection patterns are examined using three methods: linear regression, Spearman's rank correlation, and compositing techniques (not shown), all with similar results. The rank correlation method provides an alternative significance test, which is useful in narrowing some of the questions that arise for regions of low-amplitude signal

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Sanjiv Kumar, James Kinter III, Paul A. Dirmeyer, Zaitao Pan, and Jennifer Adams

. 1997 ). All climate models and the CRU TS3.1 data are regridded to a common resolution of 2.5° × 2.5° (144 × 72 global grid) using an area-average preserving method, and monthly outputs are aggregated to produce mean annual/seasonal time series for temperature. We have employed a nonparametric trend detection technique. The magnitude of trends is determined by using the Theil–Sen approach (TSA; Sen 1968 ; Theil 1950 ). If x 1 , x 2 , … , x n is a time series of length n , then the TSA

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Justin Sheffield, Suzana J. Camargo, Rong Fu, Qi Hu, Xianan Jiang, Nathaniel Johnson, Kristopher B. Karnauskas, Seon Tae Kim, Jim Kinter, Sanjiv Kumar, Baird Langenbrunner, Eric Maloney, Annarita Mariotti, Joyce E. Meyerson, J. David Neelin, Sumant Nigam, Zaitao Pan, Alfredo Ruiz-Barradas, Richard Seager, Yolande L. Serra, De-Zheng Sun, Chunzai Wang, Shang-Ping Xie, Jin-Yi Yu, Tao Zhang, and Ming Zhao

as vertical wind shear, are favorable. As the resolution of the climate models increases, the modeled storm characteristics become more realistic (e.g., Zhao et al. 2009 ). Analysis of CMIP3 models showed that the tropical cyclone-like storms produced still had many biases common of low-resolution models ( Walsh et al. 2010 ). Therefore, various dynamical and statistical techniques for downscaling tropical cyclone activity using only the CMIP3 large-scale variables have been employed ( Emanuel

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Eric D. Maloney, Suzana J. Camargo, Edmund Chang, Brian Colle, Rong Fu, Kerrie L. Geil, Qi Hu, Xianan Jiang, Nathaniel Johnson, Kristopher B. Karnauskas, James Kinter, Benjamin Kirtman, Sanjiv Kumar, Baird Langenbrunner, Kelly Lombardo, Lindsey N. Long, Annarita Mariotti, Joyce E. Meyerson, Kingtse C. Mo, J. David Neelin, Zaitao Pan, Richard Seager, Yolande Serra, Anji Seth, Justin Sheffield, Julienne Stroeve, Jeanne Thibeault, Shang-Ping Xie, Chunzai Wang, Bruce Wyman, and Ming Zhao

.5 scenario was used rather than RCP8.5. In these cases, while the results are still enlightening, we have placed the details of these analyses into the supplementary material. These include analyses of moisture transport and diurnal temperature range changes, as well as an analysis of tropical cyclone activity change using a downscaling technique with a high-resolution model. We also occasionally include a more expansive set than the core models in an individual analysis, although we comment on how

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