The Danish Meteorological Institute (DMI) also performs daily simulations of how much ice or water the Ice Sheet loses or accumulates. Based on these simulations, an overall assessment of how the surface mass balance develops across the entire Ice Sheet is obtained (Fig. 4).
At the end of the 2018 season (31 August 2018), the net surface mass balance was 517 Gt, which means that 517 Gt more snow fell than the quantity of snow and ice that melted and ran out into the sea. This number only contains the balance at the surface, and thus not the total balance, which also includes melting of glaciers and calving of icebergs.
Although the total SMB (Surface Mass Budget) for the 2016-2017 and 2017-2018 seasons are similar, development during the two seasons has been very different. Last year, the season began by gaining a lot of mass during the winter, whilst the development in SMB from the summer onwards reflected the long-term average. During the 2017-2018 season, SMB remained in line with the average from 1981-2010 until the summer, after which the development in SMB was higher than average.
The first International Polar Year, held over 1882–1883, was an important event for science. The year was the brainchild of Austrian explorer Karl Weyprecht who, after a few years on different research missions, realised that scientists were missing the big picture by not sharing information with each other.
In 1875, at the annual meeting of German Scientists and Physicians in Graz, Austria, he proposed the setting up of an observational network of research stations to monitor the Arctic climate. It was the beginning of collaborative research in the region. Today, data collected 134 years ago on temperature, air pressure, or wind speed is still freely available.
There have been two more International Polar Year events since that inaugural one, most recently in 2007–2008, along with numerous other collaborative expeditions and research missions aimed at understanding aspects of Arctic biology, ecology, climate or geology.
Winter has arrived much earlier than normal this year, particularly across North America, where cold records have been shattered.
This Thanksgiving is in fact going down as one of the coldest ever on record across the Northeast. The Washington Post here, for example, reports that Thanksgiving and Black Friday 2018 will be remembered for a record-shattering cold snap across the Northeast United States.”
Arctic sea ice, snow and ice cover rebound
Arctic sea ice volume has rebounded and is near normal levels. The sea ice trend has remained stable over the past decade and thus defy all the climate alarmist predictions of an Arctic meltdown.
As an indicator of the impacts of climate change, Arctic sea ice is hard to beat. Scientists have observed the frozen polar ocean advance and retreat at this most sensitive region of the Earth over decades for insight on the potential ripple effects on assorted natural systems: global ocean circulation, surrounding habitats and ecosystems, food sources, sea levels and more.
“We’re mostly interested in the period from the early 2000s to the present day, where we see such strong melting,” said graduate student Ian Baxter, who also works with Ding. It’s known, he added, that the effects of changes in the Arctic are no longer confined to the region and in fact spread to the mid-latitudes — often in the form of cold weather outbreaks. The group is interested in how effects in the tropics could spread beyond that region and affect the Arctic.
by Bob Weber, November 12, 2018, updated, in HuffingtonPost
There are too many polar bears in parts of Nunavut and climate change hasn’t yet affected any of them, says a draft management plan from the territorial government that contradicts much of conventional scientific thinking.
The proposed plan — which is to go to public hearings in Iqaluit on Tuesday — says that growing bear numbers are increasingly jeopardizing public safety and it’s time Inuit knowledge drove management policy.
“Inuit believe there are now so many bears that public safety has become a major concern,” says the document, the result of four years of study and public consultation.
THE CANADIAN PRESS
A draft plan from the Nunavut government says growing bear numbers are increasingly jeopardizing public safety.
The end of August traditionally marks the end of the melt season for the Greenland ice sheet as it shifts from mostly melting to mostly gaining snow.
As usual, this is the time when the scientists at DMI and our partners in the Polar Portal assess the state of the ice sheet after a year of snowfall and ice melt. Using daily output from a weather forecasting model combined with a model that calculates melt of snow and ice, we calculate the “surface mass budget” (SMB) of the ice sheet.
This budget takes into account the balance between snow that is added to the ice sheet and melting snow and glacier ice that runs off into the ocean. The ice sheet also loses ice by the breaking off, or “calving”, of icebergs from its edge, but that is not included in this type of budget. As a result, the SMB will always be positive – that is, the ice sheet gains more snow than the ice it loses.
For this year, we calculated a total SMB of 517bn tonnes, which is almost 150bn tonnes above the average for 1981-2010, ranking just behind the 2016-17 season as sixth highest on record.
By contrast, the lowest SMB in the record was 2011-2012 with just 38bn tonnes, which shows how variable SMB can be from one year to another.
Maps show the difference between the annual SMB in 2017 (left) and 2018 (right) compared with the 1981-2010 period (in mm of ice melt). Blue shows more ice gain than average and red shows more ice loss than average. (Credit: DMI Polar Portal)
What’s a good analogy for sea ice as essential polar bear habitat? Biologist Andrew Derocher claims that the soil in a forest is appropriate because without the soil you can’t have the forest ecosystem.
However, that’s a specious comparison because the amount of soil in a forest does not change markedly with the seasons the way that Arctic sea ice does.
A much better analogy is a big pond that dries up a bit every summer. The amount of habitat available to sustain aquatic plants, amphibians and insects is reduced in the dry season but many species have special adaptations for surviving reduced water availability.
Ten years ago, polar bears were classified as an endangered species due to model-based assumptions that said the recession of Arctic sea ice would hamper the bears’ seal-hunting capabilities and ultimately lead to starvation and extinction.
The Inuit, who have observed these bears catch seals in open water for generations, disagree. At least this is what scientists have found upon investigation.
“There is no evidence that the fast reduction of sea-ice habitat in the area has yet led to a reduction in population size.” (Aars et al., 2017 )
Inuit observations: “… back in early 80s, and mid 90s, there were hardly any bears … there’s too many polar bears now. Bears can catch seals even—even if the—if the ice is really thin … they’re great hunters those bears … they’re really smart … they know how to survive.” (Wong et al., 2017)
Comme mentionné dans un article précédent, le DMI (Danish Meteorological Institute) publie régulièrement l’évolution temporelle, mois par mois, de l’étendue de la glace de l’Arctique en millions de km2. Le dernier graphique publié (Fig. 1) nous montre l’étendue de la glace au mois de septembre entre 1979 et 2018 (c’est au mois de septembre que l’étendue de glace arctique est la plus faible, moins de 10 millions de km2). Une droite, dont la pente est négative, est tracée parmi les points : tous les 10 ans, la surface semble diminuer de 11,4%. Si l’on extrapole la droite ont peut calculer qu’il n’y aura plus de glace en Arctique dans 60 ans. Cependant, ne remarquez-vous rien d’étrange sur ce graphique?
It is often claimed that modern day sea ice changes are “unprecedented”, alarming, and well outside the range of natural variability. Yet scientists are increasingly finding that biomarker proxies used to reconstruct both Arctic and Antarctic sea ice conditions since the Early Holocene reveal that today’s sea ice changes are not only not unusual, there is more extensive Arctic and Antarctic sea ice during recent decades than there has been for nearly all of the last 10,000 years.
Le 14 octobre dernier, durant une interview sur la chaine de télévision CBS, le président américain a exprimé à juste titre son scepticisme concernant le rôle de l’homme sur le changement climatique.
Contrairement à l’affirmation d’Al Gore daté du 12 octobre selon laquelle seuls « quelques rares marginaux » dans la communauté scientifique ne partageraient pas l’avis du GIEC, de nombreux chercheurs sont en désaccord avec les conclusions faites par l’agence internationale.
En effet, c’était un euphémisme pour le président américain de déclarer durant l’interview « qu’il y a des scientifiques qui réfutent cela », en parlant d’un lien entre la fonte de glace au Groenlandet du changement climatique anthropique.
Le 8 octobre dernier, durant sa conférence devant la Global Warming Policy Foundation (GWPF) située à Londres, le professeur Richard Lindzen a mentionné « la découverte faite conjointement par la NOAA (la National Oceanic and Atmospheric Administration) et l’Institut Météorologique Danois, à savoir que la masse de glace du Groenland a effectivement augmenté ».