Multidimensional structure of stream flow regime in a hierarchy of landscapes within the U.S. Great Lakes basin

Abstract

AbstractStream flow data were used to evaluate a landscape hierarchy ranging from the Ontonagon River watershed (OW) to the upper peninsula of Michigan (MUP) to the entire Great Lakes basin (GLB). Flow records (1926-1988) were obtained for 45 USGS gauging stations within the GLB with drainage areas of 100-1450 sq. mi. Data were arranged in five initial matrixes with number of time series from 14 to 45. Factor analysis of average annual flow revealed from three to six patterns of stream runoff within distinct regions of the GLB. A typical watershed was selected to represent each of the five distinct regions identified for the period 1956-88, and its data were used to analyze monthly average flow values. This analysis identified two to five groupings of months with similar flow characteristics. For each annual time series of the typical five stream flow patterns of GLB regression equations were obtained from fore main indices of global atmospheric circulation. A similar analysis was completed for MUP and OW. Multilevel and multidimensional time spatial structure was discovered with factor as axis within landscape units as a homogeneous field. This kind of structure allows direct and more precise research for similar structures in atmosphere circulation and atmosphere-hydrosphere connections and regimes for entire GLB and its parts.