Date of Award

8-1-2021

Language

English

Document Type

Master's Thesis

Degree Name

Master of Science (MS)

College/School/Department

Department of Atmospheric and Environmental Sciences

Content Description

1 online resource (vi, 100 pages) : color illustrations, color maps.

Dissertation/Thesis Chair

Jeffrey Freedman

Committee Members

David Fitzjarrald

Keywords

Low-Level Jet, New York Bight, Sea Breeze, Sea breeze, Jet stream, Winds, Atmospheric circulation

Subject Categories

Atmospheric Sciences

Abstract

While the sea breeze has been studied for decades, in a complicated mid-latitude coastal region such as the New York Bight (NYB), the general thermodynamic structure and dynamics of the circulation is poorly characterized. The East Coast of the United States has become a critical area for offshore wind farm development, including a generally favorable wind resource, relatively shallow waters on an extensive continental shelf, frequent warm season sea breezes, and proximity to large populated areas. Thus the sea breeze will play a key role in the new energy economy, given the favorable wind speeds and capacity factors during periods of high power demand. The sea breeze circulation in the NYB is often amplified and complicated by other regional phenomena such as coastal morphology, a low-level jet (LLJ), and coastal upwelling. While typically considered a summertime phenomenon, there is evidence of the sea breeze circulation year-round. Long-term surface measurements in this region come from airports and offshore buoys. With the addition of wind profiling LiDAR systems both onshore (New York State Mesonet [NYSM]), and offshore (a temporary deployment by the New York State Energy Research and Development Authority [NYSERDA]), we can now continuously measure the sea breeze circulation in the vertical and better characterize the offshore wind energy environment. The NYSERDA offshore buoys, deployed at two sites in the NYB in the late summer of 2019, are the first publicly available long-term/continuous offshore wind measurements. Onshore, the profiler sites at the NYSM stations provide a better understanding of the wind environment, including profiles of wind speed and direction, within the rotor plane of an offshore wind turbine. In this study, we have created a methodology to objectively identify sea breeze days and their associated LLJs from 2010 to 2020. Along coastal Long Island, sea breeze days feature winds consistently veering to the south and strengthening at or just after 1800 UTC. Some of the filtering parameters include sky condition, sea level pressure (SLP) gradient, afternoon wind speed strength and direction tendencies, air temperature gradient, dewpoint depression, and diurnal changes in SLP. LLJs associated with the sea breeze circulation are identified using a coastal NYSM profiler site. Finally, given the complex coastal environment and distinct synoptic regimes related to the sea breeze circulation in the NYB region, sea breeze days are classified into two categories: Classic and Hybrid. A Classic sea breeze is driven primarily by both cross-shore pressure and temperature gradients, with light background winds; while a Hybrid sea breeze occurs in combination with other synoptic background activity.

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