John E. Kutzbach

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The climates of Asia are affected significantly by the extent and height of the Himalayan mountains and the Tibetan plateau. Uplift of this region began about 50 Myr ago, and further significant increases in altitude of the Tibetan plateau are thought to have occurred about 10-8 Myr ago, or more recently. However, the climatic consequences of this uplift(More)
Key risks associated with projected climate trends for the 21st century include the prospects of future climate states with no current analog and the disappearance of some extant climates. Because climate is a primary control on species distributions and ecosystem processes, novel 21st-century climates may promote formation of novel species associations and(More)
The Community Climate System Model (CCSM) has been created to represent the principal components of the climate system and their interactions. Development and applications of the model are carried out by the U.S. climate research community, thus taking advantage of both wide intellectual participation and computing capabilities beyond those available to(More)
Values for the precession and obliquity of the earth 9000 years ago indicate that the global average solar radiation for July 9000 years ago was 7 percent greater than at present. When the estimated solar radiation values are used in a low-resulation climate model, the model simulates an intensified continent-scale monsoon circulation. This result agrees(More)
Evolution of global monsoons in the Holocene is simulated in a coupled climate model—the Fast Ocean Atmosphere Model—and is also compared with the simulations in another coupled climate model—the NCAR Climate System Model. Holocene climates are simulated under the insolation forcing at 3000, 6000, 8000, and 11 000 years before present. The evolution of six(More)
We conducted the first synchronously coupled atmosphere-ocean general circulation model simulation from the Last Glacial Maximum to the Bølling-Allerød (BA) warming. Our model reproduces several major features of the deglacial climate evolution, suggesting a good agreement in climate sensitivity between the model and observations. In particular, our model(More)
We present the first synchronously coupled transient simulation of the evolution of the northern Africa climate-ecosystem for the last 6500 years in a global general circulation ocean–atmosphere–terrestrial ecosystem model. The model simulated the major abrupt vegetation collapse in the southern Sahara at about 5 ka, consistent with the proxy records. Local(More)
[1] Simulations from eight climate models and two greenhouse gas emission scenarios are used to investigate changes in the hydrologic budget of the Great Lakes region of North America and the links to large-scale hemispheric/ global changes. The ensemble average simulations indicate that increased net moisture (increased P-E) for the Great Lakes area is(More)
According to the Milankovitch theory, changes in summer insolation in the high-latitude Northern Hemisphere caused glacial cycles through their impact on ice-sheet mass balance. Statistical analyses of long climate records supported this theory, but they also posed a substantial challenge by showing that changes in Southern Hemisphere climate were in phase(More)