Computational modeling is playing an increasingly vital role in the study of atmospheric–oceanic systems. Given the complexity of the models a fundamental question to ask is, How well does the output of one model agree with the evolution of another model or with the true system that is represented by observational data? Since observational data contain measurement noise, the question is placed ...

The capability of the Climate extension of the Weather Research and Forecasting (CWRF) model in simulating the 1991 and 1998 summer floods in China is evaluated with 4-month continuous integrations as driven by the NCEP/NCAR observational reanalysis. It is shown that CWRF has a pronounced downscaling skill, capturing the key characteristics in the spatial patterns and temporal evolutions of pre...

A realistic description of how temperatures vary with elevation is crucial for ecosystem studies and for models of basin-scale snowmelt and spring streamflow. This paper explores surface temperature variability using temperature data from an array of 37 sensors, called the Yosemite Network, which traverses both slopes of the Sierra Nevada in the vicinity of Yosemite National Park, California. T...

This paper reports diagnostic and dynamical analyses about two aspects of winter storm tracks in Northern Hemisphere. It is first established with NCEP/NCAR reanalysis data that the Atlantic storm track is distinctly more intense than the Pacific storm track in 30 out of 40 winters even though the Atlantic jet is considerably weaker and that the intensity of the two storm tracks are positively ...

Water-vapor feedback is one of the important factors that determine the response of the atmosphere to surface warming. To take into account the compensating drying e ects in downdraft regions, averaging over the whole tropics is necessary. However, this operation drastically reduces the number of degrees of freedom and raises question concerning the statistical signi cance of any correlative re...

Global simulations of precipitation from climate models lack sufficient resolution and contain large biases that make them unsuitable for regional studies, such as forcing hydrologic simulations. In this study, the effectiveness of several methods to downscale large-scale precipitation is examined. To facilitate comparisons with observations and to remove uncertainties in other fields, large-sc...

Previous studies of extratropical stationary waves in the winter Northern Hemisphere (NH) often focused on effects of orography and land–ocean thermal contrast on the formation, structure, and maintenance of these waves. In contrast, research attention to tropical stationary waves was attracted by the summer monsoon circulations and the ENSO-related climate variability. Consequently, the struct...

The National Centers for Environmental Prediction–National Center for Atmospheric Research (NCEP–NCAR) reanalysis is used to estimate time trends of, and analyze the relationships among, six indices of cyclone activity or forcing for the winters of 1949–99, over the region 208–708N. The indices are Eady growth rate and temperature variance, both at 500 hPa; surface meridional temperature gradie...