Sentences with phrase «changes in sea ice cover»

Warm Greenland during the last interglacial: the role of regional changes in sea ice cover.
These new sea ice proxy records are needed (1) to fully prove the scenarios of a succession from an extended ice shelf to polynya / open - water conditions (cf., Fig. 6), (2) to reconstruct in more detail the changes in sea ice cover for early, middle and late LIG intervals characterized by very different external forcings and related internal feedback mechanisms, and (3) to allow a more fundamental proxy data / modeling comparison that results in model improvements and better reproduction of the LIG climatic evolution and prediction of future climatic scenarios20, 21,22,23, 64.
The majority of the winter warming is associated with changes in sea ice cover even though the sea ice declines at this time of the year are relatively small.
Furthermore, we must understand how changes in sea ice cover affect the feeding ecology of humpback whales and their competitors in the short - term and the dynamics of krill populations over the longer term, particularly given the increasing pressure from commercial krill harvests [36].
In other words, there has been virtually no change in sea ice cover over the last 12 years, despite the fact that atmospheric CO2 has now surpassed 410 parts per million, a considerable and steady increase over levels in 2006 which were about 380 ppm (see below, from the Scripps Oceanographic Laboratory, included in the Washington Post story 3 May 2018):

Not exact matches

Indeed, Arctic change in the last two decades has been profound — not just dwindling sea ice, but also noticeably increased precipitation, and thus snow cover, over Eurasia.
Researchers have previously suggested that extreme weather in the midlatitudes might be linked to climate change's impacts on the Arctic (SN Online: 12/2/11), particularly the dramatically decreased sea ice cover in the Arctic Ocean.
In late June, the U.S. Government Accountability Office released an assessment of how the consequences of climate change, from rising temperatures and sea levels to changes in precipitation patterns and sea ice cover, might impact the militarIn late June, the U.S. Government Accountability Office released an assessment of how the consequences of climate change, from rising temperatures and sea levels to changes in precipitation patterns and sea ice cover, might impact the militarin precipitation patterns and sea ice cover, might impact the military.
«Polar regions have been changing very rapidly, providing data for our projections on sea ice, snow cover, ice sheets and sea level rise,» says David Vaughan of the British Antarctic Survey in Cambridge, UK, the lead author of the cryosphere chapter.
But changes in sea level and ocean currents in the ice - covered regions of the Arctic and Antarctic in particular are very difficult to detect.
The outcomes of the study reveal the complexity of the processes shaping climate change in the Arctic and point to significant spatial and chronological variances in sea ice cover.
«Because these plants are photosynthetic, it's not surprising to find that as the amount of sea ice cover declined, the amount of [photosynthesis] increased,» says biological oceanographer Kevin Arrigo of Stanford University's School of Earth Sciences, who led an effort to use the MODIS (Moderate Resolution Imaging Spectroradiometer) devices on NASA's Terra and Aqua satellites to determine changes in phytoplankton growth.
Leaving aside the collapse of the Larsen - B ice shelf and other ice shelves in Antarctica, is it too simplistic to expect that dramatic changes should be anticipated first in the Arctic because it is sea covered by a few meters of sea ice and therefore more susceptible to change, in comparison to Antarctica (which is obviously land covered by glacial ice up to several kilometers thick in places)?
If proxy data can confirm that sea ice was indeed the major player in past abrupt climate - change events, it seems less likely that such dramatic abrupt changes will occur due to global warming, when extensive sea - ice cover will not be present.
Consistent with observed changes in surface temperature, there has been an almost worldwide reduction in glacier and small ice cap (not including Antarctica and Greenland) mass and extent in the 20th century; snow cover has decreased in many regions of the Northern Hemisphere; sea ice extents have decreased in the Arctic, particularly in spring and summer (Chapter 4); the oceans are warming; and sea level is rising (Chapter 5).
The findings suggest that while the response of Antarctic summer sea ice to human - caused climate change may be less dramatic than in the Arctic, sea ice cover may have declined by as much as 14 % over the last 100 years.
A number of recent studies linking changes in the North Atlantic ocean circulation to sea ice extent led Yeager to think that it would also be possible to make decadal predictions for Arctic winter sea ice cover using the NCAR - based Community Earth System Model...
Previously, Kelly was a Postdoctoral Fellow and Research Associate at the University of Washington and the University of Victoria in British Columbia, Canada where she studied the role of the changing Arctic sea ice cover on global circulation, weather, and climate using a hierarchy of numerical global climate models.
Thousands of studies conducted by researchers around the world have documented changes in surface, atmospheric, and oceanic temperatures; melting glaciers; diminishing snow cover; shrinking sea ice; rising sea levels; ocean acidification; and increasing atmospheric water vapor.
Since IPCC (2001) the cryosphere has undergone significant changes, such as the substantial retreat of arctic sea ice, especially in summer; the continued shrinking of mountain glaciers; the decrease in the extent of snow cover and seasonally frozen ground, particularly in spring; the earlier breakup of river and lake ice; and widespread thinning of antarctic ice shelves along the Amundsen Sea coast, indicating increased basal melting due to increased ocean heat fluxes in the cavities below the ice shelvsea ice, especially in summer; the continued shrinking of mountain glaciers; the decrease in the extent of snow cover and seasonally frozen ground, particularly in spring; the earlier breakup of river and lake ice; and widespread thinning of antarctic ice shelves along the Amundsen Sea coast, indicating increased basal melting due to increased ocean heat fluxes in the cavities below the ice shelvSea coast, indicating increased basal melting due to increased ocean heat fluxes in the cavities below the ice shelves.
The space agency is launching these missions at a time when decades of observations from the ground, air, and space have revealed signs of change in Earth's ice sheets, sea ice, glaciers, snow cover and permafrost.
While it is often occurring in remote regions, ongoing change with the cryosphere has impacts on people all around the world: sea level rise affects coastlines globally, billions of people rely on water from snowpack, and the diminishing sea ice that covers the Arctic Ocean plays a significant role in Earth's climate and weather patterns.
Items covered How the climate is changing with time laps charts showing the changes in Sea ice melting Ice sheet melting Carbon dioxide in the atmosphere Global temperature change Students will also explore a future technology on how to reduce the human impact on the environmeice melting Ice sheet melting Carbon dioxide in the atmosphere Global temperature change Students will also explore a future technology on how to reduce the human impact on the environmeIce sheet melting Carbon dioxide in the atmosphere Global temperature change Students will also explore a future technology on how to reduce the human impact on the environment.
If proxy data can confirm that sea ice was indeed the major player in past abrupt climate - change events, it seems less likely that such dramatic abrupt changes will occur due to global warming, when extensive sea - ice cover will not be present.
The first is to emphasize your point that degassing of CO2 from the oceans is not simply a matter of warmer water reducing CO2 solubility, and that important additional factors include changes in wind patterns, reduction in sea ice cover to reveal a larger surface for gas escape, and upwelling of CO2 from depths consequent to the changing climate patterns.
Leaving aside the collapse of the Larsen - B ice shelf and other ice shelves in Antarctica, is it too simplistic to expect that dramatic changes should be anticipated first in the Arctic because it is sea covered by a few meters of sea ice and therefore more susceptible to change, in comparison to Antarctica (which is obviously land covered by glacial ice up to several kilometers thick in places)?
We propose that past abrupt climate changes were probably a result of rapid and extensive variations in sea - ice cover.
About the only change in activity, I would expect, would involve a change in air breathing water borne sea life, that may be limited by the ice cover.
your evidence for Arctic ice concentration similar in extent or lower than current is 1) your personal experience 2) a 1952 ecyclopedia entry describing changing sea ice cover for one region of the Arctic.
All climate models tell us that it is the Arctic sea ice cover that declines first, and that Antarctic ice extent falls only later, and may even (as observed) temporarily increase in response to changing patterns of atmospheric circulation.
Re 9 wili — I know of a paper suggesting, as I recall, that enhanced «backradiation» (downward radiation reaching the surface emitted by the air / clouds) contributed more to Arctic amplification specifically in the cold part of the year (just to be clear, backradiation should generally increase with any warming (aside from greenhouse feedbacks) and more so with a warming due to an increase in the greenhouse effect (including feedbacks like water vapor and, if positive, clouds, though regional changes in water vapor and clouds can go against the global trend); otherwise it was always my understanding that the albedo feedback was key (while sea ice decreases so far have been more a summer phenomenon (when it would be warmer to begin with), the heat capacity of the sea prevents much temperature response, but there is a greater build up of heat from the albedo feedback, and this is released in the cold part of the year when ice forms later or would have formed or would have been thicker; the seasonal effect of reduced winter snow cover decreasing at those latitudes which still recieve sunlight in the winter would not be so delayed).
But in the context of what's happened in the last several years and throughout the satellite record, it's an indication that the Arctic sea ice cover is fundamentally changing.
As summer sea ice in the Arctic decreases, the snow / ice cover changes to open ocean, the amount of sunlight that is reflected drops from 80 - 90 % to about 20 %.
Lastly, there is significant independent evidence for warming in the oceans, snow cover and sea ice extent changes.
The end of the first half of the Holocene — between about 5 and 4 ka — was punctuated by rapid events at various latitudes, such as an abrupt increase in NH sea ice cover (Jennings et al., 2001); a decrease in Greenland deuterium excess, reflecting a change in the hydrological cycle (Masson - Delmotte et al., 2005b); abrupt cooling events in European climate (Seppa and Birks, 2001; Lauritzen, 2003); widespread North American drought for centuries (Booth et al., 2005); and changes in South American climate (Marchant and Hooghiemstra, 2004).
However, even a smaller figure (I had calculated about 0.17 W / m ^ 2 based on your inflated figure for total planetary albedo, but you can check it out) is still significant when compared with the total flux imbalance, which I think is a more informative comparison than an arbitrarily selected change in cloud cover, because it compares the sea ice reduction with the effects of all climate variations that have been operating in recent years..
Walt Meier, from the National Snow and Ice Data Center that collaborates in the measurements, said: «In the context of what's happened in the last several years and throughout the satellite record, it's an indication that the Arctic sea ice cover is fundamentally changing.&raqIce Data Center that collaborates in the measurements, said: «In the context of what's happened in the last several years and throughout the satellite record, it's an indication that the Arctic sea ice cover is fundamentally changing.&raquin the measurements, said: «In the context of what's happened in the last several years and throughout the satellite record, it's an indication that the Arctic sea ice cover is fundamentally changing.&raquIn the context of what's happened in the last several years and throughout the satellite record, it's an indication that the Arctic sea ice cover is fundamentally changing.&raquin the last several years and throughout the satellite record, it's an indication that the Arctic sea ice cover is fundamentally changing.&raqice cover is fundamentally changing
«The changes are happening so fast in the Arctic — with sea - ice loss, with increased time of no snow cover — that that's really the driving feature.
Overview of changes in Arctic sea ice cover.
A central topic will be teleconnections in the climate system, i.e. how a change in climate in one part of the globe (e.g. temperatures in the Atlantic or shrinking sea ice cover in the Arctic) can influence climate on other parts of the globe (e.g. Eurasian winter temperatures), and how we can use this information to improve regional climate prediction and therefore regional climate service.
From the figures I took an average value of 0.45 — but, hey, if you prefer to assume 0.35, that's OK, because it will not change the conclusion that the observed Arctic sea ice melt has not appreciably changed our planet's total albedo, and that a very small change in cloud cover would have a far greater effect.
UK Guardian Claim: «In another marker of climate change, Arctic sea ice cover was the third smallest since record - keeping began in 1979.&raquIn another marker of climate change, Arctic sea ice cover was the third smallest since record - keeping began in 1979.&raquin 1979.»
NSIDC scientists have observed fundamental changes in the Arctic's sea ice cover.
Solar partitioning in a changing Arctic sea - ice cover.
With impacts on Arctic coastal communities and increases in maritime activities, both observations of changes underway and predictions at the scale of less than a week to several months out are of importance to the research community and those living and operating in ice - covered seas.
The aim of the C - SIDE working group is to reconstruct changes in sea - ice extent in the Southern Ocean for the past 130,000 years, reconstruct how sea - ice cover responded to global cooling as the Earth entered a glacial cycle, and to better understand how sea - ice cover may have influenced nutrient cycling, ocean productivity, air - sea gas exchange, and circulation dynamics.
The Arctic sea - ice cover is in the midst of a major transformation, with the Pacific Arctic sector and Alaska experiencing some of the most profound changes in ice cover anywhere in the Arctic.
Evidence suggests that the negative phase of the Arctic Oscillation was driven in part by warm air (air warmed by the dramatic seasonal loss of Arctic sea ice) 9 as well as by changes in snow cover over Eurasia driven by climate change.10 This event is part of an emerging trend in which a warming climate may paradoxically bring colder, snowier winters to northern Europe and the eastern United States.11
And remember, the satellite data are one small part of a vast amount of data that overwhelmingly show our planet is warming up: retreating glaciers, huge amounts of ice melting at both poles, the «death spiral» of arctic ice every year at the summer minimum over time, earlier annual starts of warm weather and later starts of cold weather, warming oceans, rising sea levels, ocean acidification, more extreme weather, changing weather patterns overall, earlier snow melts, and lower snow cover in the spring...
They explain how, overall, Antarctic sea ice cover (frozen sea surface), for separate reasons involving wind changing in relation to the location of certain warming sea water currents, shows a slight upward trend, though it also shows significant melting in some areas.
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