A Study of Topographically Forced Mesoscale Circulations

该项目的主要目标是增进对北美西部对流层低层的几个重要中尺度特征的基本了解，这些特征是由该区域的复杂地形产生的。将更加重视被沿海地形所困的低层现象，例如从加利福尼亚州巴哈到不列颠哥伦比亚省海岸几百公里范围内观察到的沿海南风和沿岸涌浪。与沿海偏南气流密切相关的是中尺度沿海涡流，例如在加利福尼亚州附近观测到的那些涡流(如卡塔琳娜涡流)。第二个项目将是研究美国地面气压的日变化和半日变化，以创造一个有价值的诊断工具，并更好地了解日气压变化的中尺度变化和物理机制。拟议研究的最后一个组成部分将是对中尺度低谷的检查。这种低谷与普吉特湾会聚带有关，并促成了1979年胡德运河大桥的破坏。

The primary objective of this project is to increase basic understanding of several important mesoscale features of the lower troposphere of western North America that are produced by the complex terrain of the region. The greater emphasis will be given to low-level phenomena that are trapped by the coastal topography such as the coastal southerlies and along shore surges that are observed within a few hundred kilometers of the coast from Baja, California to British Columbia. Closely connected with the coastal southerly currents re mesoscale coastal eddies, such as those observed off California (e.g. the Catalina eddy). A second project will be to examine the diurnal and semi diurnal surface pressure variations over the United States both to create a valuable diagnostic tool and to better understand the mesoscale variations and physical mechanisms of diurnal pressure change. The final component of the proposed research will be the examination of the mesoscale troughing. Such troughing is associated with the Puget Sound convergence zone and contributed to the destruction of the Hood Canal Bridge in 1979.