Characterizing Anomalous Mid-tropospheric Ridges and Their Trends
Here we present some initial analyses to contribute to the characterization of these ridges. Using NCEP Reanalysis fields of 500 millibar geopotential height on timescales ranging from daily to seasonal to annual means, we show some of the salient features of the anomalous ridges, including intensity, duration, spatial patterns, and relationships with extreme temperature and precipitation events. We provide an analysis of trends and relative frequencies of occurrence, and compare these to the overall variability of the 500 mb geopotential height field. We also present some suggestions for potential forcing and feedback mechanisms that may help to better understand anomalous ridges.