Sea Breeze Sensitivity to Coastal Upwelling and Synoptic Flow Using Lagrangian Methods

Abstract

Sea breezes occur nearly daily in the U.S. Mid‐Atlantic summer during high electricity demand periods, and thus have important implications for the burgeoning U.S. offshore wind energy industry. The sea breeze's offshore component is poorly understood and ill defined relative to its onshore counterpart. Here a new Lagrangian method not yet readily used to study the sea breeze, relative dispersion, was validated and applied to a validated Weather Research and Forecasting model in the U.S. Mid‐Atlantic. This Lagrangian method is used to characterize the onshore convergent and offshore divergent sea breeze extents and intensities, and test their sensitivities to both atmospheric synoptic flow and oceanic coastal upwelling, another common summer season regional phenomenon. It was found that offshore‐directed synoptic flow impacted the sea breeze onshore extent more than offshore extent, and that coastal upwelling did not significantly impact sea breeze onshore or offshore extent for these carefully selected case studies. Upwelling, however, produced an earlier sea breeze onset (~5 hr), and a shallower, sharper, and more intense offshore/onshore sea breeze during strong offshore synoptic flow, consistent with past studies. The offshore side of the sea breeze cell—with stronger intensity during upwelling—crossed the New Jersey Wind Energy Area at ~1900 UTC, regardless of synoptic wind or upwelling conditions. Results overall are consistent with dynamic linear sea breeze theory. Uncertain projected trends in coastal upwelling/sea breezes in a warming world highlight the importance of continued study of coastal air‐sea interactions for improved offshore wind energy assessment and prediction.

Validation of RU-WRF, the Custom Atmospheric Mesoscale Model of the Rutgers Center for Ocean Observing Leadership

“…the surface from the persistent well-studied subsurface cold-water feature known as the Mid-Atlantic Cold Pool. This upwelling affects local and regional horizontal temperature gradients and influences the offshore wind resource, particularly sea breezes (Seroka et al 2018). The coldest-pixel product uses satellite observations from the Advanced Very High Resolution Radiometer (AVHRR), as do most SST products.…”

Dynamics of the Land–Sea Breeze System and the Surface Current Response in South-West Australia

“…As the land-ocean temperature difference drives the LSB system, processes that affect the ocean temperatures, such as coastal upwelling have an influence on the LSB system [14]. Coastal upwelling also produced an earlier sea breeze onset, and a shallower, sharper, and more intense offshore/onshore sea breeze [14].…”

Analyzing the Synoptic‐, Meso‐ and Local‐ Scale Involved in Sea Breeze Formation and Frontal Characteristics

“…In this way, we are able to evaluate how the synoptic, mesoscale, and local forcings that lead to SB formation are represented in the model. There are plenty of investigations that evaluate the relevant influence of for instance the synoptic flow on SB characteristics (Mestayer et al, ; Seroka et al, ; Steele et al, ), but as a result of using fixed thresholds, we infer the existence of systematic biases or patterns giving rise to discrepancy in the model. More adequate representations of these forcings are fundamental to achieve precise forecasts of SB phenomena and their implications in the ABL at coastal regions.…”

“…The evolution of the atmospheric boundary layer (ABL) in coastal areas is influenced by the sea breeze (SB) circulation, which is dominant during the warmest months of the year when the synoptic forcing is quiescent and the insolation important. In particular, the SB has been widely investigated due to its influence on the diffusion of pollutants (Borge et al, 2008;Clappier et al, 2000;Papanastasiou, Melas & Lissaridis 2010), the generation of wind energy offshore (Archer et al, 2014;Seroka et al, 2018;Steele et al, 2013), convection and precipitation (Azorín-Molina et al, 2014;Comin et al, 2015), the transport and recirculation of relevant gases (Ahmadov et al, 2007;Gangoiti et al, 2001;Hernádez-Ceballos et al, 2015;Zahorowski et al, 2008), and the forecasting of maximum temperatures in coastal regions during hot spells (Meir et al, 2013;Papanastasiou, Melas, Bartzanas et al, 2010). Around 40% of the population lives within 100 km of the coast (SEDAC, 2019); therefore, the understanding and adequate representation of the SB in mesoscale numerical models are highly relevant.…”