Publications

The Subseasonal North Atlantic Oscillation is a Quasi-Semiannual, Propagating Disturbance

Published: 2025

The North Atlantic Oscillation (NAO) is a well-studied mode of regional climate variability, associated with fluctuations in sea-level pressure (SLP), storm tracks, and the North Atlantic jet. These fluctuations have been perceived as a seesawing between two climatic phases, one corresponding to a more poleward jet and the other to a more equatorward. However, recent work has shown that zonal wind anomalies also propagate poleward at interseasonal timescales. Using reanalysis data, this work demonstrates for the first time that the…

Recommended citation: Smith, S., P. Staten, and J. Lu, 2025: The Subseasonal North Atlantic Oscillation is a Quasi-Semiannual, Propagating Disturbance. Submitted. doi: 10.31223/X5S432.1.

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Diabatic Eddy Forcing Increases Persistence and Opposes Propagation of the Southern Annular Mode in MERRA2

Published in Journal of Atmospheric Science, 2024

As a dominant mode of jet variability on sub-seasonal timescales, the Southern Annular Mode (SAM) provides a window into how the atmosphere can produce internal oscillations on longer-than-synoptic timescales. While SAM’s existence can be explained by dry, purely barotropic theories, the timescale for its persistence and propagation is set by a lagged interaction between barotropic and baroclinic mechanisms, making the exact physical mechanisms challenging to identify and to simulate, even in latest generation models. By partitioning the eddy momentum flux…

Recommended citation: Smith, S., J. Lu, and P. Staten, 2024: Diabatic Eddy Forcing Increases Persistence and Opposes Propagation of the Southern Annular Mode in MERRA2. Journal of Atmospheric Science. doi: 10.1175/JAS-D-23-0019.1.

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How Moist and Dry Intrusions Control the Local Hydrologic Cycle in Present and Future Climates

Published in Journal of Climate, 2021

Models disagree on how much the hydrologic cycle could intensify under climate change. These changes are expected to scale with the Clausius–Clapeyron relation but may locally diverge due in part to the uncertain response of the general circulation, causing the hydrologic cycle to inherit this uncertainty. To identify how the circulation contributes, we link circulation changes to changes in the higher moments of the hydrologic cycle using the novel dynamical framework of the local hydrologic cycle, the portion of the…

Recommended citation: Smith, S., P. Staten, and J. Lu, 2021: How Moist and Dry Intrusions Control the Local Hydrologic Cycle in Present and Future Climates. Journal of Climate. doi: 10.1175/JCLI-D-20-0780.1

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