Upper-ocean Response to Precipitation Forcing in an Ocean Model Hindcast of Hurricane GonzaloSource: Journal of Physical Oceanography:;2020:;volume( ):;issue: -::page 1Author:Steffen, John;Bourassa, Mark
DOI: 10.1175/JPO-D-19-0277.1Publisher: American Meteorological Society
Abstract: Pre-existing, oceanic barrier layers have been shown to limit turbulent mixing and suppress mixed layer cooling during the forced stage of a tropical cyclone (TC). Furthermore, an understanding of barrier layer evolution during TC passage is mostly unexplored. High precipitation rates within TCs provide a large freshwater flux to the surface that alters upper-ocean stratification and can act as a potential mechanism to strengthen the barrier layer. Ocean glider observations from the Bermuda Institute of Ocean Sciences (BIOS) indicate that a strong barrier layer developed during the approach and passage of Hurricane Gonzalo (2014), primarily as a result of freshening within the upper 30 m of the ocean. Therefore, an ocean model case study of Hurricane Gonzalo has been designed to investigate how precipitation affects upper-ocean stratification and sea surface temperature (SST) cooling during TC passage.Ocean model hindcasts of Hurricane Gonzalo characterize the upper-ocean response to TC precipitation forcing. Three different vertical mixing parameterizations are tested to determine their sensitivity to precipitation forcing. For all turbulent mixing schemes, TC precipitation produces near-surface freshening of about 0.3 psu, which is consistent with previous studies and in situ ocean observations. The influence of precipitation-induced changes to the SST response is more complicated, but generally modifies SSTs by ± 0.3 °C. Precipitation forcing creates a dynamical coupling between upper-ocean stratification and current shear that is largely responsible for the heterogeneous response in modeled SSTs.
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contributor author | Steffen, John;Bourassa, Mark | |
date accessioned | 2022-01-30T18:04:12Z | |
date available | 2022-01-30T18:04:12Z | |
date copyright | 9/17/2020 12:00:00 AM | |
date issued | 2020 | |
identifier issn | 0022-3670 | |
identifier other | jpod190277.pdf | |
identifier uri | http://yetl.yabesh.ir/yetl1/handle/yetl/4264438 | |
description abstract | Pre-existing, oceanic barrier layers have been shown to limit turbulent mixing and suppress mixed layer cooling during the forced stage of a tropical cyclone (TC). Furthermore, an understanding of barrier layer evolution during TC passage is mostly unexplored. High precipitation rates within TCs provide a large freshwater flux to the surface that alters upper-ocean stratification and can act as a potential mechanism to strengthen the barrier layer. Ocean glider observations from the Bermuda Institute of Ocean Sciences (BIOS) indicate that a strong barrier layer developed during the approach and passage of Hurricane Gonzalo (2014), primarily as a result of freshening within the upper 30 m of the ocean. Therefore, an ocean model case study of Hurricane Gonzalo has been designed to investigate how precipitation affects upper-ocean stratification and sea surface temperature (SST) cooling during TC passage.Ocean model hindcasts of Hurricane Gonzalo characterize the upper-ocean response to TC precipitation forcing. Three different vertical mixing parameterizations are tested to determine their sensitivity to precipitation forcing. For all turbulent mixing schemes, TC precipitation produces near-surface freshening of about 0.3 psu, which is consistent with previous studies and in situ ocean observations. The influence of precipitation-induced changes to the SST response is more complicated, but generally modifies SSTs by ± 0.3 °C. Precipitation forcing creates a dynamical coupling between upper-ocean stratification and current shear that is largely responsible for the heterogeneous response in modeled SSTs. | |
publisher | American Meteorological Society | |
title | Upper-ocean Response to Precipitation Forcing in an Ocean Model Hindcast of Hurricane Gonzalo | |
type | Journal Paper | |
journal title | Journal of Physical Oceanography | |
identifier doi | 10.1175/JPO-D-19-0277.1 | |
journal fristpage | 1 | |
journal lastpage | 50 | |
tree | Journal of Physical Oceanography:;2020:;volume( ):;issue: - | |
contenttype | Fulltext |