Causes and impacts on middle latitudes, global and planetary change 2014, doi. Multimedia gallery ecological consequences of seaice. Implications of arctic sea ice decline for the earth system alaska. Record of recent seaice loss one of the most conspicuous consequences of recent anthropogenic warming has been declining annual minimum extent of arctic sea ice 7. In the antarctic the extent of the sea ice has been growing at a rate of 1. Arctic sea ice is melting 1991 2010 median 19792000. One problem in truly divining a trend was the lack of continuity there was a twoyear data gap in the 1970s between the esmr data and the successor smmr data, hindering. To assess whether demographic declines of arctic species at the southern limit of their range will be gradual or punctuated, we compared largescale environmental patterns including sea ice dynamics to ringed seal pusa hispida reproduction, body condition, recruitment, and stress in hudson bay from 2003 to 20. Nilas, pancake, and ice raft photographs courtesy don perovich, cold regions. Seaice loss emerges as an important driver of marine and terrestrial ecological dynamics, influencing productivity, species interactions, population mixing, gene flow, and pathogen and disease transmission. Empirical evidence for such effects is limited, however, particularly at the local population and community levels. Individual pieces pile up to form rafts and eventually solidify 3 rd image. Supplementary information blogs used for this study.
A new record for minimum area of arctic sea ice was set in 2012, and backto. In recent decades, sea ice in the arctic ocean has been melting faster than it refreezes in winter. And not only is the ice extent getting smaller, but the ice is also thinning at an alarming rate. Arctic seaice loss is already having a significant impact. The intergovernmental panel on climate change ipcc fourth assessment report states that greenhouse gas forcing is predominantly responsible for the decline in arctic sea ice extent. Seaice loss emerges as an important drive r of marine and terrestrial ecological dynamics. The science of climate change arctic vulnerabilities and. By that time, in 1989, people were talking about global warming and its possible consequences, including effects on sea ice and other variables, parkinson said. Sea ice begins as thin sheets of smooth nilas in calm water top or disks of pancake ice in choppy water 2 nd image. Impacts of changes in sea ice and other environmental parameters. By denying the impacts of agw on polar bears, bloggers aim to cast doubt on other established ecological consequences of agw, aggravating the consensus. Nasa arctic sea ice decline shakes up ocean ecosystems.
The changes in the arctic are manifested by the decline in the sea ice, permafrost, glaciers and the greenland ice sheet stroeve et al. The global impacts of rapidly disappearing arctic sea ice. Impacts of changing seaice conditions on arctic marine mammals. Water below sea ice has a higher concentration of salt and is denser than the surrounding ocean water, so it sinks and moves from the surface. Few people understand that the arctic sea ice death spiral represents more than just a major ecological upheaval in the worlds far north. Ecological effects of fishing the pew charitable trusts. In recent decades, rapid warming has contributed to a yearround decline in sea ice thickness and a 50% reduction in ice area during summer months. How disappearing sea ice has put arctic ecosystem under threat this article is more than 3 years old from algae to fish and polar bears, the loss of habitat caused by global warming is affecting. Arctic seaice loss has widespread effects on wildlife. A 2007 study found the decline to be faster than forecasted by model simulations.
Alfred wegener institute for polar and marine research. The major decline in sea ice that has taken place in the arctic since 2000 has become an iconic climate change signal. Effects of arctic sea ice decline on weather and climate. The contribution of declining arctic sea ice to warming in the region through arctic amplification suggests that sea ice decline has the potential to influence ecological dynamics in terrestrial arctic systems. One of the major potential consequences of rapid and pronounced arctic warming is the development of an icefree summer arctic ocean 9, which will have largescale environmental consequences that. Bob van oort at cicero center for climate and environmental. We show that much of the scientific evidence indicating that some polar bear subpopulations are declining due to climate changemediated sea ice. After successive years of melting, the consequences are likely to be felt further afield with scientists suggesting weather patterns in. In the arctic, sea ice is about 10 feet 3 meters thick on average, while ice at the south pole averages one mile 1. Demographic and traditional knowledge perspectives on the.
Sea ice extent has continued to decline during september, reaching below four million square kilometers early in the month. Sea ice still declining, despite antarcticas gains. Sea ice affects both landbased and oceanbased ecosystems. Sea ice floats, so when it melts, it does not raise sea levels. Over time, large sheets of ice collide, forming thick pressure ridges along the margins 4 th image. The arctic is warming at roughly twice the global rate and has seen a dramatic decline of summer sea ice as a result. Consistency and discrepancy in the atmospheric response to arctic.
This finding is contrary to the deleterious effects that declining sea ice is having on habitats of icedependent animals, such as polar bear and walrus. Arctic sea ice decline shakes up ocean ecosystems 11. But warmer temperatures in the arctic are causing another type of ice to disappear as well. While sea ice is perhaps the most defining feature of the habitat. Evidence of the age of arctic sea ice suggests that fewer patches of ice are persisting for multiple years i. Many scientists suspect that the deterioration results from a combination of global warming and other climate cycles. Pdf after a decade with nine of the lowest arctic seaice minima on record, including the historically low minimum in 2012, we synthesize recent. After a decade with nine of the lowest arctic seaice minima on record, including the historically low minimum in 2012, we synthesize recent developments in the study of ecological responses to seaice decline.
Ice algae algae that live in and under the sea ice also serve as a nutritional basis for animals living at great depths algae that live in and under the sea ice play a much greater role for the arctic food web than previously assumed. The proportion of sea ice five years or older has declined dramatically over the recorded time period, from more than 30 percent of september ice in the. Diminished sea ice has reduced food availability for some populations of polar bears7 and walruses8. In fact, some computer models project we are on track to see an icefree summer within 20 years. Ecological impacts 19 damage to coral reefs 19 shifting species ranges and yearly cycles 20 declining arctic animal populations 20. Declines in the arctic sea ice are arguably the most dramatic evidence of the effects of current climate warming on ocean systems. Some of the most important climate news this winter has been around the alarming lack of sea ice in the arctic, which has been in decline due to the steady rise in earths average air and ocean temperatures. Synthesis of socialecological changes related to arctic oil and gas development. Ecological implications of changes in the arctic cryosphere. Snow, land ice and sea ice shrinking snowpack vanishing glaciers polar ice disintegration 16 melting permafrost and damage to infrastructure 17 part iv.
Because pack ice is dynamic, pieces can collide and form much thicker ice. Some sea ice holds fast to a coastline or the sea floor fast icewhile pack ice drifts with winds and currents. In this way, sea ice contributes to the circulation of the global ocean conveyor belt. She used satellite records of the extent of sea ice at both poles and combined them to get the global trend, which mirrors the decline of the arctic. Generating an epub file may take a long time, please be patient. Ecological consequences of fishing 7 challenges to recovery of overfished species 11 iii. What are the consequences of arctic sea ice decline.
Future sea ice conditions in western hudson bay and consequences for polar bears in the 21st century. Records show that arctic sea ice is at its lowest point in 1,500 years and continues to melt at an accelerated rate. Seaice loss emerges as an important driver of marine and terrestrial ecological dynamics, influencing productivity, species interactions, population. The global impacts of arctic sea ice loss the student. Impacts of climate warming, declining sea ice on arctic. Advancing plant phenology and reduced herbivore production.
Arctic sea ice decline and continental cold anomalies. Can be estimated using various modelling and ecological approaches. Here, focusing on arctic sea ice and polar bears, we show that blogs that deny or downplay agw disregard the overwhelming scientific evidence of arctic seaice loss and polar bear vulnerability. Five reasons why sea ice decline should be front page news. Impact of declining arctic sea ice on winter snowfall. Introduction the recent dramatic decline in summer sea ice extent in the arctic ocean has underlined the variability and the potential impact of sea ice variability on climate and weather in northern europe and the arctic itself. The oceans around antarctica are changing rapidly, with average rates of warming and freshening that greatly exceed the global.
Upstream and downstream effects of greenland blocking xiaodan chen1,2 and dehai luo1 1cas key laboratory of regional climateenvironment for temperate east asia, institute of atmospheric physics, chinese academy of science, beijing, china, 2college of earth sciences, university of chinese academy of sciences. Time series orthoimagery showing coastal erosion from 1948 to 2010 at the smith river on the arctic coastal plain of. A framework for assessing the economic impacts of arctic change. The influence of declining sea ice on shipping activity in. Fulton,5 mark hebblewhite,6 jeffrey kerby,1 susan j. The decline of arctic sea ice in recent decades has occurred at a more rapid rate than predicted by most climate change models. Walruses that used to rest and nurse their young on sea ice in summer are now forced to come ashore in large aggregations how is diminishing arctic sea ice in. Bycatch 16 causes of bycatch and effects on marine species 16 seabirds 18 marine mammals 19 sea turtles 19 bycatch trends and magnitude in. Pdf ecological consequences of seaice decline researchgate. Ecological consequences of seaice decline eric post,1 uma s. In the past decade, multiyear sea ice was reduced at three. Despite the growth in knowledge about the effects of a warming arctic on its coldadapted species, the mechanisms by which these changes affect animal populations remain poorly understood.
The decline of arctic sea ice also has profound global climatic effects, or feedbacks, that are already intensifying global warming and have the potential to destabilize the climate system. Changes in sea ice have begun to affect hunting and traditional overice transport routes, which. How the arctic wildlife and humans will be affected by the continued melting of arctic sea. Pdf sea ice in the arctic is one of the most rapidly changing. Demographic, ecological, and physiological responses of. For most of the year, sea ice is typically covered by snow. Synthesis of socialecological information related to oil and gas development. Sea ice in the arctic has declined in terms of overall extent, thickness, proportion of myi and seasonal duration.
The ecological consequences of changes in arctic sea ice are outlined in a recent paper in science here. Impacts of changing seaice conditions on arctic marine. Walker9 after a decade with nine of the lowest arctic seaice minima on record, including the historically low. Internet blogs, polar bears, and climatechange denial by. For the period of the available satellite data record since the late 1970s, arctic sea ice extent has been decreasing in all months, with the most pronounced loss in september.
Our message is not simple or conventional or consistent with the dire warnings present in much of the polar bear literature since 2006 schliebe et al. Potential ecosystem impacts of the decline of seasonal sea ice in the arctic created date. Reduced sea ice is also almost certain to lead to increased shipping, tourism and exploration for oil, gas and mineral resources details in hovelsrud et al. Walker9 after a decade with nine of the lowest arctic sea ice minima on record, including the historically low. Most biologically productive sector of the arctic marine system is the bering and chukchi seas. Since satellite records began in 1978, summer and autumn sea ice extent has decreased approximately 50 percent, an amount roughly equal to half the area of the continental united states. The sea ice extent at the end of the melt season is on a decline. Sea ice determines the interaction between marine and terrestrial species, influences ocean.
Potential ecosystem impacts of the decline of seasonal sea. Heres what vanishing sea ice in the arctic means for you. Ecological consequences of sea ice decline eric post,1 uma s. Arctic seaice loss has widespread effects on wildlife date. March and september monthly average arctic sea ice extent, 19792016. Arctic sea ice now starts melting 11 days earlier and it starts refreezing 26 days later than it used to, on average see figure 3. The ocean is salty and when sea ice forms, much of the salt is pushed into the ocean water below the ice, although some salt may become trapped in small pockets between ice crystals. This figure shows arctic sea ice extent for the months of september and march of each year from 1979 through 2016. The rapid decline in arctic sea ice asi extent, area and volume during. Leadsnarrow, linear openings ranging in size from meters to kilometerscontinually form and disappear. A synthesis of remotesensing studies, ground observations. Ecological consequences of seaice decline eric post et al. Ecological consequences of seaice decline image 2 a caribou, photographed in early may.
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