Zhang
Tao
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Tao
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ArticleNorth American climate in CMIP5 experiments. Part II: evaluation of historical simulations of intraseasonal to decadal variability(American Meteorological Society, 2013-12-01) Sheffield, Justin ; Camargo, Suzana J. ; Fu, Rong ; Hu, Qi ; Jiang, Xianan ; Johnson, Nathaniel ; Karnauskas, Kristopher B. ; Kim, Seon Tae ; Kinter, Jim ; Kumar, Sanjiv ; Langenbrunner, Baird ; Maloney, Eric ; Mariotti, Annarita ; Meyerson, Joyce E. ; Neelin, J. David ; Nigam, Sumant ; Pan, Zaitao ; Ruiz-Barradas, Alfredo ; Seager, Richard ; Serra, Yolande L. ; Sun, De-Zheng ; Wang, Chunzai ; Xie, Shang-Ping ; Yu, Jin-Yi ; Zhang, Tao ; Zhao, MingThis is the second part of a three-part paper on North American climate in phase 5 of the Coupled Model Intercomparison Project (CMIP5) that evaluates the twentieth-century simulations of intraseasonal to multidecadal variability and teleconnections with North American climate. Overall, the multimodel ensemble does reasonably well at reproducing observed variability in several aspects, but it does less well at capturing observed teleconnections, with implications for future projections examined in part three of this paper. In terms of intraseasonal variability, almost half of the models examined can reproduce observed variability in the eastern Pacific and most models capture the midsummer drought over Central America. The multimodel mean replicates the density of traveling tropical synoptic-scale disturbances but with large spread among the models. On the other hand, the coarse resolution of the models means that tropical cyclone frequencies are underpredicted in the Atlantic and eastern North Pacific. The frequency and mean amplitude of ENSO are generally well reproduced, although teleconnections with North American climate are widely varying among models and only a few models can reproduce the east and central Pacific types of ENSO and connections with U.S. winter temperatures. The models capture the spatial pattern of Pacific decadal oscillation (PDO) variability and its influence on continental temperature and West Coast precipitation but less well for the wintertime precipitation. The spatial representation of the Atlantic multidecadal oscillation (AMO) is reasonable, but the magnitude of SST anomalies and teleconnections are poorly reproduced. Multidecadal trends such as the warming hole over the central–southeastern United States and precipitation increases are not replicated by the models, suggesting that observed changes are linked to natural variability.
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ArticleOcean Sciences with the Spilhaus Projection: A Seamless Ocean Map for Spatial Data Recognition(Nature Research, 2023-06-24) Chen, Jie ; Zhang, Tao ; Tominaga, Masako ; Escartin , Javier ; Kang, RuixinThe ocean, as a vast interconnected body of water on Earth, plays an essential role in Earth’s planetary dynamics, climate change, and the evolution of human society and decision-making processes. An ocean-focused global map is necessary to visually capture numerous phenomena within the world’s ocean and seafloor. Here we present the power of the Spilhaus square projection with various geological and geophysical datasets, including bathymetry, teleseismicity, seafloor geography, and seafloor spreading parameters. The Spilhaus projection, compared to widely-used map projections (e.g., Mercator and Robinson), emphasizes the seamless connection of water masses surrounded by continents. This projection has recently garnered attention for presenting ocean-oriented data, although it is not extensively used and currently supported by the ArcGIS software. Maps presented here provide not only a novel geological perspective on the world ocean as a whole body, but also new insights/questions to be addressed regarding features and processes of the water body, the seafloor, and ocean-atmosphere dynamics, which can be used for research, education, media, and policy decisions, and promote similar approaches.