(Table 2) Foehn characteristics of station in the McMurdo Dry Valleys, Antarctica


Autoria(s): Speirs, Johanna C; Steinhoff, Daniel F; McGowan, Hamish A; Bromwich, David H; Monaghan, Andrew J
Cobertura

MEDIAN LATITUDE: -77.623000 * MEDIAN LONGITUDE: 162.503618 * SOUTH-BOUND LATITUDE: -77.828000 * WEST-BOUND LONGITUDE: 160.656800 * NORTH-BOUND LATITUDE: -77.378000 * EAST-BOUND LONGITUDE: 163.418000 * DATE/TIME START: 2007-05-21T03:15:00 * DATE/TIME END: 2007-05-22T17:00:00 * MINIMUM ELEVATION: 20.0 m * MAXIMUM ELEVATION: 1176.0 m

Data(s)

27/10/2010

Resumo

Foehn winds resulting from topographic modification of airflow in the lee of mountain barriers are frequently experienced in the McMurdo Dry Valleys (MDVs) of Antarctica. Strong foehn winds in the MDVs cause dramatic warming at onset and have significant effects on landscape forming processes; however, no detailed scientific investigation of foehn in the MDVs has been conducted. As a result, they are often misinterpreted as adiabatically warmed katabatic winds draining from the polar plateau. Herein observations from surface weather stations and numerical model output from the Antarctic Mesoscale Prediction System (AMPS) during foehn events in the MDVs are presented. Results show that foehn winds in the MDVs are caused by topographic modification of south-southwesterly airflow, which is channeled into the valleys from higher levels. Modeling of a winter foehn event identifies mountain wave activity similar to that associated with midlatitude foehn winds. These events are found to be caused by strong pressure gradients over the mountain ranges of the MDVs related to synoptic-scale cyclones positioned off the coast of Marie Byrd Land. Analysis of meteorological records for 2006 and 2007 finds an increase of 10% in the frequency of foehn events in 2007 compared to 2006, which corresponds to stronger pressure gradients in the Ross Sea region. It is postulated that the intra- and interannual frequency and intensity of foehn events in the MDVs may therefore vary in response to the position and frequency of cyclones in the Ross Sea region.

Formato

text/tab-separated-values, 82 data points

Identificador

https://doi.pangaea.de/10.1594/PANGAEA.837426

doi:10.1594/PANGAEA.837426

Idioma(s)

en

Publicador

PANGAEA

Direitos

CC-BY: Creative Commons Attribution 3.0 Unported

Access constraints: unrestricted

Fonte

Supplement to: Speirs, Johanna C; Steinhoff, Daniel F; McGowan, Hamish A; Bromwich, David H; Monaghan, Andrew J (2010): Foehn Winds in the McMurdo Dry Valleys, Antarctica: The Origin of Extreme Warming Events. Journal of Climate, 23(13), 3577-3598, doi:10.1175/2010JCLI3382.1

Palavras-Chave #Beacon_Valley2; Canada_Gl; Comment; Commonw_Gl; DATE/TIME; Date/time end; Event label; Explorers_Cove2; Howard_Gl; Humidity, relative, minimum; International Polar Year (2007-2008); IPY; Lake_Bonney; Lake_Fryxell2; Lake_Hoare2; Lake_Vanda2; Lake_Vida; McMurdo Dry Valleys, southern Victorica Land, Antarctica; Station; Taylor_Gl; Taylor Valley, East Antarctica; Temperature, air, maximum; Temperature, air, minimum; Unmanned weather station/meteorological observation; UWST; Victoria Valley, East Antarctica; Wind direction; Wind speed, gust; Wright Valley, East Antarctica
Tipo

Dataset