Archives par mot-clé : Arctic

Arctic Sea Ice Extent

by DMI (Danish Meterological Institute), July 2017


The graphic shows the mean September sea ice extent on the northern hemisphere. The plotted values correspond approximately to the sea ice area that ‘survived’ the summer melt in the respective years

The graph illustrates a decreasing trend in sea ice extent since 1978, with annual variations of occationally more than 1 million square kilometres. The 2012 sea ice minimum extented set a new minimum record.

See also here

The Holocene context for Anthropogenic Global warming

by Ed Hoskins, June1, 2015


When considering the scale of temperature changes that alarmists anticipate because of Man-made Global Warming and their view of the disastrous effects of additional Man-made Carbon Dioxide emissions in this century, it is useful to look at climate change from a longer term, century by century and even on a millennial perspective.

(i) See also here

(ii) See also here

Contamination of the Arctic reflected in microbial metagenomes from the Greenland ice sheet

by A.L. Hauptmann et al., July 11, 2017


Globally emitted contaminants accumulate in the Arctic and are stored in the frozen environments of the cryosphere. The microbial potential to degrade anthropogenic contaminants, such as toxic and persistent polychlorinated biphenyls, was found to be spatially variable and not limited to regions close to human activities.

Skillful prediction of northern climate provided by the ocean

by M. Arthur et al., June 20, 2017, in Nature Communication


We show that variations in ocean temperature in the high latitude North Atlantic and Nordic Seas are reflected in the climate of northwestern Europe and in winter Arctic sea ice extent. Statistical regression models show that a significant part of northern climate variability thus can be skillfully predicted up to a decade in advance based on the state of the ocean. Particularly, we predict that Norwegian air temperature will decrease over the coming years, although staying above the long-term (1981–2010) average. Winter Arctic sea ice extent will remain low but with a general increase towards 2020.

Norway offers oil firms record number of Arctic blocks

by AFP/UKnews, June 21, 2017


Norway on Wednesday proposed to open up a record number of blocks in the Barents Sea to oil exploration despite protests from environmentalists and others fearing possible damage to the Arctic region.

The Norwegian oil and energy ministry offered oil companies 93 blocks in the Barents Sea and nine others in the Norwegian Sea, all located beyond the Arctic Circle.

Threshold in North Atlantic-Arctic Ocean circulation controlled by the subsidence of the Greenland-Scotland Ridge

by Michael Stars et al., June 5, 2017 in Nature Communication


High latitude ocean gateway changes are thought to play a key role in Cenozoic climate evolution. However, the underlying ocean dynamics are poorly understood. Here we use a fully coupled atmosphere-ocean model to investigate the effect of ocean gateway formation that is associated with the subsidence of the Greenland–Scotland Ridge. We find a threshold in sill depth (50 m) that is linked to the influence of wind mixing.

Early 20th-century Arctic warming intensified by Pacific and Atlantic multidecadal variability

by Hiroki Tokinaga et al., PNAS, May 1, 2017


Arctic amplification is a robust feature of climate response to global warming, with large impacts on ecosystems and societies. A long-standing mystery is that a pronounced Arctic warming occurred during the early 20th century when the rate of interdecadal change in radiative forcing was much weaker than at present. Here, using observations and model experiments, we show that the combined effect of internally generated Pacific and Atlantic interdecadal variabilities intensified the Arctic land warming in the early 20th century.

Are methane seeps in the Arctic slowing global warming?

by Randall Hayman, May 8, 2017, in Science


Good news about climate change is especially rare in the Arctic. But now comes news that increases in one greenhouse gas—methane—lead to the dramatic decline of another. Research off the coast of Norway’s Svalbard archipelago suggests that where methane gas bubbles up from seafloor seeps, surface waters directly above absorb twice as much carbon dioxide (CO2) as surrounding waters. The findings suggest that methane seeps in isolated spots in the Arctic could lessen the impact of climate change.

Taking The Economist to Task for Unfounded Climate Catastrophe Fearmongering

by   Dr. John D. Harper, FGSA,FGAC, PGeol., former director of the Geological Survey of Canada © May 2017


I have recently been asked to comment on three articles published in The Economist. My background for such a response is as a Professor of Petroleum Geology and Sedimentology (ret.), a former Director-Energy for the Geological Survey of Canada, a former researcher in industry, and as an academic researcher on sea level changes and climate documentation through geologic time, Natural Resources of the Future and a couple of decades of studies in the Arctic.

1) Skating on thin ice: The thawing Arctic threatens an environmental catastrophe. Apr 27, 2017

2) The Arctic as it is known today is almost certainly gone. April 29, 2017

3) Thaw point: As the Arctic melts the world’s weather suffers. April 29, 2017

Methane seeps in the Canadian high Arctic

by Geological Society of America, April 13, 2017

in ScienceDaily


Cretaceous climate warming led to a significant methane release from the seafloor, indicating potential for similar destabilization of gas hydrates under modern global warming. A field campaign on the remote Ellef Ringnes Island, Canadian High Arctic, discovered an astounding number of methane seep mounds in Cretaceous age sediments.

Influence of high-latitude atmospheric circulation changes on summertime Arctic sea ice

by Q. Ding et al., March 13, 2017, Nature Climate Change


The Arctic has seen rapid sea-ice decline in the past three decades, whilst warming at about twice the global average rate. Yet the relationship between Arctic warming and sea-ice loss is not well understood. Here, we present evidence that trends in summertime atmospheric circulation may have contributed as much as 60% to the September sea-ice extent decline since 1979.

Egalement : Recul de la banquise arctique: 30% à 50% lié à la variabilité naturelle de l’atmosphère