Science. 1990 Jan 12;247(4939):192-5. doi: 10.1126/science.247.4939.192.
Simulations from a global climate model with and without orography have been used to investigate the role of mountains in maintaining extensive arid climates in middle latitudes of the Northern Hemisphere. Dry climates similar to those observed were simulated over central Asia and western interior North America in the experiment with mountains, whereas relatively moist climates were simulated in these areas in the absence of orography. The experiments suggest that these interior regions are dry because general subsidence and relatively infrequent storm development occur upstream of orographically induced stationary wave troughs. Downstream of these troughs, precipitation-bearing storms develop frequently in association with strong jet streams. In contrast, both atmospheric circulation and precipitation were more zonally symmetric in the experiment without mountains. In addition, orography reduces the moisture transport into the continental interiors from nearby oceanic sources. The relative soil wetness of these regions in the experiment without mountains is consistent with paleoclimatic evidence of less aridity during the late Tertiary, before substantial uplift of the Rocky Mountains and Tibetan Plateau is believed to have occurred.
利用包含和不包含地形的全球气候模式进行了模拟，以研究山脉在维持北半球中纬度地区广泛干旱气候中的作用。在有地形的实验中，模拟出了与中亚和北美的内陆地区类似的干旱气候，而在没有地形的情况下，这些地区的模拟气候相对湿润。实验表明，这些内陆地区之所以干燥，是因为在地形引起的定常波槽上游，普遍存在下沉和相对较少的风暴发展。在这些槽的下游，与强急流相关的降水风暴频繁发展。相比之下，在没有山脉的实验中，大气环流和降水更为纬向对称。此外，地形减少了来自附近海洋源的水分向大陆内部的输送。在没有山脉的实验中，这些地区的相对土壤湿度与上新世后期（据信落基山脉和青藏高原的大规模抬升之前）相对湿润的古气候证据一致。
