Antarctic Peninsula Climate Variability: Historical and Paleoenvironmental Perspectives

10.1029/ar079 ◽  
2003 ◽  
2021 ◽  
Author(s):  
Ibeth Celia Rojas Macedo ◽  
Wilson Alfredo Suarez Alayza ◽  
Edwin Anibal Loarte Cadenas ◽  
Katy Damacia Medina Marcos

<p>This research aims to explain the influence of climatic variables (temperature and precipitation) in King George Island (KGI) glacier shrinkage on the Antarctic Peninsula. It employed Landsat satellite images from 1989 to 2020, climatic data and ONI index from 1980 to 2019.</p><p>King George Island glaciers have lost 10% of their coverage in the last 31 years. Greater glacier shrinkage was shown until the first mid-period assessed, while the retreat rate slowed down for the second half of the studied period. Furthermore, of 73 KGI glaciers, 37% were marine- and land-terminating, 42% were land-terminating and 21% were sea-terminating. Nonetheless, the decreases in the ice-coverage of marine-contact glaciers (35% of glacier coverage reduced) were higher than land-terminating glaciers (17% of glacier coverage reduced).</p><p>There was a perceivable fluctuation in annual average air temperature for the 1980-2006 period. Nevertheless, from around 2007 to 2015/2016 there was a slight continuous cooling period and precipitation was somewhat above the average. Therefore, these patterns could explain the recent KGI glacier-retreat deceleration.</p><p>Unlike the 1982/1983 and 1997/1998 El Niño events, the 2015/2016 El Niño was colder with precipitation reduction from the sustained annual amount (since roughly 2007 to 2015/2016) to values below the average. Moreover, during the 2015/2016 El Niño, KGI glacier coverage reduction was the lowest for the 31 year-long evaluated. However, it was revealed that the glacier's height could increase by accumulation in El Niño years, but glacier mass balance could be more negative due to basal melting. Additionally, land-terminating glaciers have lost more glacier coverage than sea-terminating glaciers throughout this ENSO event.</p><p>Hence, climate variability might play a significant role in KGI glacier shrinkage, but calving process, glacier features and so on, further a combination of them should be assessed to reach a better understanding of KGI glacier retreat.</p>


1998 ◽  
Vol 27 ◽  
pp. 623-627 ◽  
Author(s):  
Christoph Schneider

The glaciers of the Antarctic Peninsula are believed to react rapidly to climatic fluctuations. Thus it is of great interest to find methods for monitoring regional climate variability in this region, Two small glaciers on the Antarctic Peninsula were chosen to monitor the accumulation and ablation pattern of the snow cover in respect to climate variations. During two summer seasons, synthetic aperture radar pulse-repetition interval images from the European ERS-1 active microwave satellite instrument were collected. Simultaneously, micro-meteorological measurements with simple automatic weather stations were carried out at three locations on the glaciers. Energy available for snowmelt was computed using the bulk transfer equations. Incorporating a digital terrain model and a model for shortwave irradiance, estimates of the energy available for melt were then calculated for the entire glaciers. The resulting time series of spatially distributed information on available energy can be used to separate periods and areas with snow-melt from periods and areas with completely frozen snow cover. The same separation can be achieved from the ERS-1 imagery. Integrating both the remote-sensing technique and the ground observations, it may be possible to establish a combined method to monitor the effects of weather patterns on a seasonal basis.


2016 ◽  
Vol 31 (1) ◽  
pp. 131-147 ◽  
Author(s):  
Loïc Barbara ◽  
Xavier Crosta ◽  
Amy Leventer ◽  
Sabine Schmidt ◽  
Johan Etourneau ◽  
...  

2021 ◽  
Vol 13 (6) ◽  
pp. 1122
Author(s):  
Eduardo Santamaría-del-Ángel ◽  
Mary-Luz Cañon-Páez ◽  
Maria-Teresa Sebastiá-Frasquet ◽  
Adriana González-Silveira ◽  
Angelica-L. Gutierrez ◽  
...  

This study aimed to describe the interannual climate variability in the West Antarctic Peninsula (WAP) under austral summer conditions. Time series of January sea-surface temperature (SST) at 1 km spatial resolution from satellite-based multi-sensor data from Moderate Resolution Imaging Spectrometer (MODIS) Terra, MODIS Aqua, and Visible Infrared Imager Radiometer Suite (VIIRS) were compiled between 2001 and 2020 at localities near the Gerlache Strait and the Carlini, Palmer, and Rothera research stations. The results revealed a well-marked spatial-temporal variability in SST at the WAP, with a one-year warm episode followed by a five-year cold episode. Warm waters (SST > 0 °C) reach the coast during warm episodes but remain far from the shore during cold episodes. This behavior of warm waters may be related to the regional variability of the Antarctic Circumpolar Current, particularly when the South Polar Front (carrying warm waters) reaches the WAP coast. The WAP can be divided into two zones representing two distinct ecoregions: the northern zone (including the Carlini and Gerlache stations) corresponds to the South Shetland Islands ecoregion, and the southern zone (including the Palmer and Rothera stations) corresponds to the Antarctic Peninsula ecoregion. The Gerlache Strait is likely situated on the border between the two ecoregions but under a greater influence of the northern zone. Our data showed that the Southern Annular Mode (SAM) is the primary driver of SST variability, while the El Niño Southern Oscillation (ENSO) plays a secondary role. However, further studies are needed to better understand regional climate variability in the WAP and its relation with SAM and ENSO; such studies should use an index that adequately describes the ENSO in these latitudes and addresses the limitations of the databases used for this purpose. Multi-sensor data are useful in describing the complex climate variability resulting from the combination of local and regional processes that elicit different responses across the WAP. It is also essential to continue improving SST approximations at high latitudes.


2016 ◽  
Vol 29 (17) ◽  
pp. 6109-6125 ◽  
Author(s):  
Damien Irving ◽  
Ian Simmonds

Abstract The Pacific–South American (PSA) pattern is an important mode of climate variability in the mid-to-high southern latitudes. It is widely recognized as the primary mechanism by which El Niño–Southern Oscillation (ENSO) influences the southeast Pacific and southwest Atlantic and in recent years has also been suggested as a mechanism by which longer-term tropical sea surface temperature trends can influence the Antarctic climate. This study presents a novel methodology for objectively identifying the PSA pattern. By rotating the global coordinate system such that the equator (a great circle) traces the approximate path of the pattern, the identification algorithm utilizes Fourier analysis as opposed to a traditional empirical orthogonal function approach. The climatology arising from the application of this method to ERA-Interim reanalysis data reveals that the PSA pattern has a strong influence on temperature and precipitation variability over West Antarctica and the Antarctic Peninsula and on sea ice variability in the adjacent Amundsen, Bellingshausen, and Weddell Seas. Identified seasonal trends toward the negative phase of the PSA pattern are consistent with warming observed over the Antarctic Peninsula during autumn, but are inconsistent with observed winter warming over West Antarctica. Only a weak relationship is identified between the PSA pattern and ENSO, which suggests that the pattern might be better conceptualized as a preferred regional atmospheric response to various external (and internal) forcings.


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