Influence of the North Atlantic Subtropical High on wet and dry sea-breeze events in North Carolina, United States

• Published in: Investigaciones Geográficas
• Main Authors: Luchetti, Nicholas T., Nieto Ferreira, Rosana, Rickenbach, Thomas M., Nissenbaum, Mark R., McAuliffe, Joel D.
• Other Authors: Climate and Large-Scale Dynamics and the Physical and Dynamic Meteorology programs of the National Science Foundation’s Division of Atmospheric and Geospatial Sciences, Award AGS-1118141.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Universidad de Alicante 2017
• Subjects: Sea breeze; precipitation; North Carolina; North Atlantic Subtropical High; wind direction; wind speed; Brisa marina; lluvia; Carolina del Norte; alta Subtropical del Atlántico Norte; vientos de escala sinóptica; Alta; Inglés; Nash; Sigla; Sudeste; North Atlantic
• Online Access: https://www.investigacionesgeograficas.com/article/view/2017-n68-influence-of-the-north-atlantic-subtropical-high-in-north-carolina; https://doi.org/10.14198/INGEO2017.68.01

The sea-breeze (SB) is an important source of summertime precipitation in North Carolina (NC, southeast United States). However, not all SB events produce precipitation. A climatology of wet and dry SB events in NC is used to investigate the conditions that are conducive to precipitation associated with the sea breeze.Radar imagery was used to detect 88 SB events that occurred along the NC coast between May-September of 2009-2012. The majority (85%) of SB events occurred during offshore flow (53%) or during flow that was parallel to the coast (22%). SB events were separated into dry (53%) and wet (47%) events and differences in the dynamic and thermodynamic parameters of the environment in which they formed were analyzed. Significant differences in dynamic and thermodynamic conditions were found. SB dry events occurred under stronger winds (6.00 ± 2.36 ms-1) than SB wet events (4.02 ± 2.16 ms-1). Moreover, during SB wet events larger values of convective available potential energy and lower values of convective inhibition were present, conditions that favor precipitation. Overall, the SB wet events accounted for 20-30% of the May-September precipitation along the NC coastal region. The position of the North Atlantic Subtropical High (NASH) controls both moisture availability and winds along the NC coast, thus providing a synoptic-scale control mechanism for SB precipitation. In particular, it was shown that when the NASH western ridge is located along the southeast coast of the United States, it causes a moist southwesterly flow along the NC coast that may favor the occurrence of SB wet events. La brisa marina (BM) es una importante fuente de precipitación de verano en Carolina del Norte (NC en su sigla en inglés), sudeste de Estados Unidos. Sin embargo, no todos los eventos de BM producen precipitación. En este trabajo se utiliza una climatología de eventos de BM lluviosos y secos en NC para investigar las condiciones que conducen a la precipitación.Se utilizaron imágenes de radar para detectar 88 eventos de ...