The high-resolution Weather Research and Forecasting (WRF) model is coupled to the Princeton Ocean Model (POM) to investigate
the effect of air-sea interaction during Typhoon Kaemi that formed in the Northwest Pacific at 0000 UTC 19 July 2006. The
coupled model can reasonably reproduce the major features of ocean response to the moving tropical cyclone (TC) forcing, including
the deepening of ocean mixed layer (ML), cooling of sea surface temperature (SST), and decaying of typhoon. 相似文献
Observational and bogus satellite data are directly assimilated into the Weather Research and Forecasting (WRF) model in simulations of Typhoon Kalmaegi (2008). The data assimilation is performed using the Radiative Transfer for TIROS-N Operational Vertical Sounder (RTTOV) model and the three-dimensional variational data assimilation (3DVAR) technique, with satellite observations taken from the National Oceanic and Atmospheric Administration-16 (NOAA-16) Advanced TIROS Vertical Sounder (ATOVS) system composed of the High-resolution Infrared Radiation Sounder (HIRS), the Advanced Microwave Sounding Unit-A (AMSU-A), and the Advanced Microwave Sounding Unit-B (AMSU-B). Data assimilation experiments are initialized at three different times. Improvements in the numerical simulation of the typhoon are discussed in the context of wind, temperature, pressure, and geopotential fields. The results indicate that assimilation of satellite data can improve both the representation of the initial conditions and the subsequent simulation of the typhoon. Different satellite data have different impacts on the typhoon track. In these simulations, data from AMSU-A play a greater role in improving the simulation of the typhoon than data from AMSU-B or HIRS. Assimilation of satellite data significantly affects the simulation of the subtropical high and the steering of the typhoon by the environmental flow. The subtropical high is enhanced and extends westward in the data assimilation experiments. The background flow therefore steers the typhoon more westward, improving the simulated typhoon track. Although direct assimilation of satellite brightness temperature improves the simulated environmental conditions, it does not significantly improve the simulated intensity of the typhoon. By contrast, initializing the typhoon simulation using bogus data in tandem with satellite data improves not only the environmental conditions but also the simulated inner-core structure of the typhoon. Assimilation of both types of data therefore improves the simulation of both the typhoon track and the typhoon intensity. The results of these experiments offer new insight into improving numerical simulations of typhoons. 相似文献
The breeding habitat selection by houbara bustards in Mori, Xinjiang, China during the breeding seasons from April to June 1998–2000 was studied. Most of habitats chosen for breeding were short sub-shrubby and open areas close to high bushy patches. The nesting females clearly prefer low covered areas and avoid densely covered and high vegetation sites. The number of herb species was significantly smaller at nest sites than at randomly selected sites. Only the distance to the closest fox den contributed the most to discrimination between successful and predated nests. The average distance to the closest fox den was significantly longer at successful nests than at depredated nests. Vegetative density, plant species richness, topography and distance to the closest fox den are possibly the most important factors that determined the nest sites selection of houbara bustard. The displaying males clearly prefer low covered areas and avoid densely covered and high vegetation sites. The vegetation density and number of plant species at display sites was significantly lower than that at randomly selected sites. The average distance to the closest bushy patch was significantly shorter at display sites than at random sites. Plant species richness, vegetative density, vegetative cover and distance to the bushy patches are possibly the most important factors for the display sites selection of houbara bustard
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