Archives par mot-clé : Antarctic

Estimating the extent of Antarctic summer sea ice during the Heroic Age of Antarctic Exploration

by T. Edimburgh and J. Day, November 21, 2017, in TheCryopshere

In stark contrast to the sharp decline in Arctic sea ice, there has been a steady increase in ice extent around Antarctica during the last three decades, especially in the Weddell and Ross seas. In general, climate models do not to capture this trend and a lack of information about sea ice coverage in the pre-satellite period limits our ability to quantify the sensitivity of sea ice to climate change and robustly validate climate models

Surprise: Defying Models, Antarctic Sea Ice Extent 100 Years Ago Similar To Today

by P. Gosselin, October 17, 2017 in NoTricksZone

from Dr. L. Lüning and Prof. F. Vahrenbolt

Satellite measurements of Antarctic sea ice do not go back even 40 years. That’s not very much, especially when we consider that many natural climate cycles have periods of 60 years and more.

Luckily we have the field of climate reconstruction. Using historical documents and sediment cores, the development of ice cover can be estimated. In November, 2016, Tom Edinburg and Jonathan Day examined shipping log books from the time of Antarctic explorers and published on ice extent in The Cryosphere (…)

Antarctique: des milliers de bébés manchots meurent de faim en terre Adélie

by l’express, 13 october 2017

La découverte a été effectuée par des scientifiques français du CNRS, dans ce groupe qui vivait sur l’île de Petrels, en terre Adélie. Hormis les deux bébés manchots survivants, ils n’ont retrouvé que des corps d’animaux affamés et des oeufs non-éclos. Ces chercheurs, soutenus par le Fonds mondial pour la nature (WWF), observaient depuis 2010 cette colonie. Selon eux, l’étendue inhabituelle de la banquise a contraint les parents à aller plus loin chercher leur nourriture. Leur progéniture ont succombé à la faim.

News From Vostok Ice Cores

by Richard Taylor, October 6, 2017 in WUWT

A Russian team, however, has been active establishing a chronology of deuterium from snow-cores and -pits near the Vostok station (A.A. Ekaykin, et al., 2014). A summary ( with digital data became available in May, 2017. The data include annual measurements from 1654 to 2010, providing an overlap with the ice-core record that enables an assessment of present conditions from the perspective of ice-core record.

Sea Ice Extent Sinks to Record Lows at Both Poles

by Maria-José Vinas, August 4, 2017 in

“It is tempting to say that the record low we are seeing this year is global warming finally catching up with Antarctica,” Meier said. “However, this might just be an extreme case of pushing the envelope of year-to-year variability. We’ll need to have several more years of data to be able to say there has been a significant change in the trend.”

Evidence for Little Ice Age in Antarctica

by UC Santa Cruz Newscenter, August 31, 2017 in WUWT

Changes in the sources of nitrogen and the composition of the phytoplankton community are more likely to account for the differences seen in the isotope data, Huckstadt said. “It looks more like a shift at the base of the food web, probably related to the transition from the Little Ice Age to current conditions, causing changes in the phytoplankton community,” he said.

See also: “Here we present new data from the Ross Sea, Antarctica, that indicates surface temperatures were ~ 2 °C colder during the LIA, with colder sea surface temperatures in the Southern Ocean and/or increased sea-ice extent, stronger katabatic winds, and decreased snow accumulation.”

Discovery of Additional West Antarctic Volcanoes Furthers Natural over Man-Made Warming

by James E Kamis, August 23, in ClimateChangeDispatch

The now three-year-old Plate Climatology Theory is on the brink of total confirmation. This is the result of two just-released and very telling Antarctic research studies. Combining the results of these two studies with the massive amounts of pre-existing data it is possible to show with very high certainty that melting of West Antarctic glaciers is directly related to bedrock heat flow and chemically charged heated fluid flow from the 5,000-mile-long West Antarctic Rift System (see Figure 1).

Study validates East Antarctic ice sheet to remain stable even if western ice sheet melts

by Indiana University, August 17, 2017 in ScienceDaily

“There are models that predict that the interior of the East Antarctic ice sheet wouldn’t change very much, even if the West Antarctic ice sheet was taken away,” Licht said. According to these models, even if the ice sheet’s perimeter retreats, its core remains stable.

See also here and here

Record-shattering 2.7-million-year-old ice core reveals start of the ice ages

by Paul Voosen, August 15, 2017

Scientists announced today that a core drilled in Antarctica has yielded 2.7-million-year-old ice, an astonishing find 1.7 million years older than the previous record-holder


If the new result holds up, says Yige Zhang, a paleoclimatologist at Texas A&M University in College Station, the proxies will need to be recalibrated. “We have some work to do.”

Scientists discover 91 volcanoes below Antarctic ice sheet

by Robin McKie, August 12, 2017 The Guardian

The Edinburgh volcano survey, reported in the Geological Society’s special publications series, involved studying the underside of the west Antarctica ice sheet for hidden peaks of basalt rock similar to those produced by the region’s other volcanoes. Their tips actually lie above the ice and have been spotted by polar explorers over the past century.

See also here and here

Des scientifiques découvrent 91 nouveaux volcans sous les glaciers de l’Antarctique