a Center for Natural and Technological Hazards and Department of Geography, University of Utah, Salt Lake City, UT 84112, USA b United States Geological Survey, Southwest Biological Science Center, Sonoran Desert Research Station, BioSciences East Building, Tucson, AZ 85721, USA c Department of Biology, University of Utah, Salt Lake City, UT 84112, USA d Department of Soil, Water and Environmen...

Complex sociopolitical, economic, and geographical realities cause the 20 million residents of Mexico City to suffer from some of the worst air pollution conditions in the world. Greenhouse gas emissions from the city are also substantial, and opportunities for joint local-global air pollution control are being sought. Although a plethora of measures to improve local air quality and reduce gree...

In this paper, three-dimensional ultrasonic anemometer and multi-channel have been used to monitor the flow field of a subway station in Beijing. Based on releasing sulfur hexafluoride (SF6) hall, gas transmission diffusion range studied. The results show that under natural ventilation, would be controlled by regular mainstream field. Because obvious subsidence heavy tends accumulate ground. ai...