排序方式： 共有4条查询结果，搜索用时 0 毫秒
1
1.
2.
Subregionalization of Low-Frequency Summer Drought Variability in the Southeastern United States 总被引：1，自引：0，他引：1
Jason T. Ortegren Ashley Weatherall Justin T. Maxwell 《The Professional geographer》2013,65(2):323-332
Freshwater resources are particularly limited in the Southeastern United States. In recent years, severe summer droughts have placed substantial strain on municipal and industrial water resources, emphasizing the need for further research on the causes of long-term moisture deficits. Previous research has identified a Southeast drought region and specific low-frequency ocean-atmosphere influences on drought. In this article, we identify three distinct subregions of low-frequency summer drought variability in the Southeastern United States using principal components analysis. Multidecadal drought variability is most pronounced in the Southeastern Atlantic Coastal States (SEACS) subregion. The SEACS drought variability is significantly associated with ocean-atmosphere variability in the Atlantic and Pacific basins. The significance of ocean-atmosphere influences on drought in the Southeast is spatially confined within only the SEACS subregion. The Eastern Gulf States (EGS) subregion exhibits a long-term increase in summer moisture that is significantly associated with Northern Hemisphere surface temperature increases during the last century. The peninsular Florida subregion is characterized by high-frequency drought variability that is not associated with any of the climate indexes included in this study. 相似文献
3.
基于监督分类分区域的特征因子提取 总被引：1，自引：0，他引：1
以南充市2000年8月的LandsatTM影像为信息源,利用监督分类方法对南充市的土地利用进行了分类,采用了分区域提取特征因子这一改进方法,有效地降低混合像元带来的影响,提高土地利用信息的精度。 相似文献
4.
1