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Over recent decades, analyses of the structure and impact of atmospheric teleconnections have substantially increased our understanding of the climate system and the role of climate variability. Moving beyond simple correlations between teleconnection indices and temperature and precipitation anomalies, synoptic climatology has been able to provide insight on the spatiotemporal manifestation of teleconnection anomalies, as well as further understanding in terms of teleconnection-related anomalies in circulation pattern frequencies that can lead to extreme events over individual areas. In this progress report, we focus on a number of recent papers that, broadly defined, assess two realms of teleconnections: the North Atlantic circulation, largely focusing on the North Atlantic Oscillation; and the north and tropical Pacific circulation, as manifest in El Niño–Southern Oscillation, the Pacific North American pattern, and the Pacific Decadal Oscillation. In each of these two regions, we highlight the major goals and results of recent synoptic research. [ABSTRACT FROM PUBLISHER]

The semi-arid US Intermountain West is characterized by complex hydroclimatic variability, influenced both by topography and by atmosphere and ocean processes operating over a large range of time and space scales. Understanding climate–hydrology interactions has become increasingly important as demands on water resources grow from both within and beyond the region, particularly in light of projected climate changes. This paper reviews key atmospheric and oceanic controls that impact the Intermountain West’s water supply, how those controls vary over multiple timescales, the tree-ring record of hydroclimatic variability in the region, projected climate change impacts, and research needs for the future. Water availability in the Intermountain West is largely influenced by interrelated atmospheric features that include the strength and position of the Pacific subtropical high, the intensity and geographic location of the Aleutian low, the latitude of the westerly storm track, and teleconnections such as the Pacific North American pattern and the El Niño−Southern Oscillation system. The tree-ring record of pre-instrumental conditions in the Intermountain West indicates that there have been droughts in the past that were more severe than those experienced in the historical record. Climate model projections of future moisture-related changes, including decreased snowpack and changing seasonality of precipitation, may exacerbate strain on the region’s water supply. Advances in climate modeling and in our understanding of climate variability over multiple time and space scales would improve capacity for water resource management in the Intermountain West. [ABSTRACT FROM PUBLISHER]