Abstract: In a previous study of the extratropical Northern Hemisphere wintertime circulation, significant variations were described in the occurrence of anomalies that persist beyond the durations associated with synoptic-scale ...

Abstract: We have conducted observational analysts to identify systematic aspects of the life cycles of persistent anomalies of the extratropical Northern Hemisphere wintertime circulation. In the present study, we focus on the ...

Abstract: Observational analyses are performed to examine the roles of remote and local forcing in the evolutions of the extreme U.S. summer heat wave-drought cases of 1980 and 1988. At early stages, both events are associated with ...

Abstract: Earlier studies of persistent large-scale flow anomalies have been extended, with the aim of identifying the primary mechanisms for persistent anomaly development. In this study the focus is on wintertime cases of persistent ...

Abstract: A simple two-layer quasigeostrophic model is employed to investigate the sensitivity of storm tracks to changes in an externally imposed, zonally varying large-scale flow. Zonally asymmetric temperature and horizontal ...

Abstract: The present study extends our previous work on the life cycles of persistent anomalies by providing more comprehensive analyses of the synoptic and dynamical characteristics associated with the developments of the anomalies. ...

Abstract: We have studied the geographical and regional persistence characteristics of wintertime Northern Hemisphere 500 mb height anomalies, focusing particular attention on the behavior of strong anomalies that persist beyond the ...

Abstract: For the population Of cyclones that formed over North America and the adjacent Atlantic Ocean during the Genesis of Atlantic Lows Experiment (GALE; 13 January-16 March 1986), a variety of interrelationships between various ...

Abstract: The relationship between the time-mean planetary-scale deformation field and the structure of midlatitude storm tracks is studied in wintertime simulations of the National Center for Atmospheric Research (NCAR) Community ...

Abstract: The origin of the Northern Hemisphere summer subtropical anticyclones is investigated using a linear quasigeostrophic model. It is found that the broad features in the model solutions forced by realistic heating fields ...