Melting of Arctic Sea Ice Already Setting Records in 2016
A new and fuller summary of this year’s Arctic winter by the U.S. National Snow and Ice Data Centre (NSIDC) confirms the preliminary announcement last week that sea ice reached its annual maximum extent on March 24 this year.
Covering an area of 14.52m square kilometers, this year’s peak winter extent is a shade smaller than the previous record low set in 2015. But the new NSIDC report adds a lot more detail about what it calls a “highly unusual” and “most interesting” Arctic winter.
With abnormally warm conditions right across the Arctic, some regions experienced temperatures 4-8C higher than average. While this meant slower ice growth in some places, in others it caused a dramatic thinning by 30cm in one week, according to early model results.
Reaching a Peak
Arctic sea ice ebbs and flows with the seasons, reaching a maximum extent for the year in February or March and a minimum in September, at the end of the summer melt period.
This year, scientists were still waiting expectantly at the end of March, explains the NSIDC report:
“Very early in the month, extent declined, raising anticipation that an early maximum had been reached. However, after a period of little change, extent slowly rose again, reaching the seasonal maximum on March 24.”
As late as a week ago, scientists still hadn’t ruled out the possibility of a late season surge. But sea ice extent has dropped off quite a bit since then, suggesting the peak has been and gone.
You can see this year’s sea ice behavior in the graph below from NSIDC, which shows sea ice extent over the 2015/6 winter (blue line) up to April 3 compared to previous years.
Arctic sea ice’s indecisive behavior throughout March meant it finally reached its maximum extent quite late in the year, 12 days later than the 1981-2010 average.
This isn’t significant in itself, says NSIDC, since the timing of the winter maximum can vary quite a lot from year to year, occurring as early as February 24 in 1996 or as late as April 2 in 2010.
This year’s winter peak reached 14.52m square kilometers or 1.12m square kilometers below the 1981-2010 average (compare the blue line with the grey line in the graph above).
At 13,000 square kilometers under the previous record set in February 2015, this year bears the title of smallest winter maximum on record by only the slimmest of margins.
In fact, it’s within the margins of error that NSIDC uses to estimate sea ice extent, says Prof. Andrew Shepherd, professor of earth observation at the University of Leeds.
Technically-speaking, that means 2016 ties with 2015 for the lowest winter peak on record, he tells Carbon Brief.
But what about the winter as a whole?
This Winter in Context
A number of factors influence sea ice cover from year to year, so the value for any month, season or year isn’t necessarily smaller than the previous one.
That said, Arctic sea ice in January was lower in 2016 than in any previous year. The same was true for February. March 2016 saw the second lowest sea ice extent in the satellite record (which dates back to 1979), says NSIDC, with 40,000 square kilometers more ice than the previous record set in 2015.
You can see the annual ups and downs in March sea ice extent in the graph below (black line). The trend over time, however, is clearly downwards. The blue line shows the decline in March sea ice extent of 2.7 percent per decade since 1979.
What’s behind this winter’s low ice extent?
The Arctic is warming more than twice as fast as the global average, largely in response to rising greenhouse gases.
In March 2016, nearly all of the Arctic Ocean experienced exceptionally warm conditions, says the NSIDC report, with air temperatures about 3,000 feet above the surface typically 2 to 4C higher than the long term average.
“It has been a pretty unusual winter with a lot warmer temperatures than usual, especially over Greenland, Svalbard and the Canadian Arctic. We had a brief cold spell for a couple of weeks in February over Greenland, but, otherwise, temperatures have been well above average.”
Temperatures nearer the Pole reached as high as 4-8C warmer than usual, the NSIDC report explains:
“As an exclamation point on the unusual warmth, there was a brief weather event at the very end of December 2015 when air temperatures near the Pole nearly reached the melting point.”
The strange December weather event also caused high temperatures in the Kara and Barents Seas, the report notes. According to the PIOMAS model which estimates sea ice thickness, sea ice in this region thinned by up to 30cm in the week between Dec. 28, 2015 and Jan. 4 (blue shading in the map below).
As well as the ongoing human-induced warming trend in the Arctic, the report attributes some of the particularly low sea ice extent in the Kara and Barents Seas tothe influx of warm Atlantic waters to the region.
But the scientists’ efforts to unravel the many different contributions to such unusual warmth across the Arctic are still ongoing, the report adds:
“The reasons for the persistent warmth over the entire Arctic this past winter are currently under investigation; a link with the strong El Niño pattern of this winter may be involved.”
While the unusual warmth across the Arctic “helped to keep ice extent especially low” over winter, according to the NSIDC report, it’s likely there were other factors at play, too. Prof. Julienne Stroeve, a senior research scientist at NSIDC, tells Carbon Brief:
“The slow ice growth is in part from warmer than normal air temperatures in the Arctic, but also winds that have helped to keep ice in the Barents Sea from expanding southwards.”
Sea Ice Thickness
Monitoring the health of sea ice in the Arctic means knowing about how ice thickness has fared this winter as well as extent—and the winter isn’t over yet on that front, says Shepherd. He tells Carbon Brief:
“Although NSIDC’s data show that the peak extent of Arctic sea ice this winter tied with the record low of 2015, we know that ocean water continues to freeze on to the ice base through April.”
The latest observations of sea ice thickness from the CryoSat satellite show that the ice was, on average, 1.8m thick in March, says Shepherd. This is about 10cm thinner than the same time last year, but about 10cm thicker than the record winter low in 2013.
Shepherd and his team will use measurements of thickness together with sea ice extent to estimate the volume of ice left at the end of winter. These results aren’t public yet, but Shepherd tells Carbon Brief it’s not looking hopeful:
“If things continue as in previous years, I suspect this year could see a tie with that record low for volume as well, but it’s too early to say for sure.”
Less Old Ice, More Young Ice
Monitoring sea ice thickness can tell us about the age of the ice that’s left in the Arctic, as well as how it’s changing over short timescales. The oldest ice—more than five years old—is now at record low levels, making up just 3 percent of the total ice cover, according to the NSIDC report.
Of the sea ice in the Arctic basin, 70 percent is first-year ice (which means it’s melting and refreezing each year) while only 30 percent is lasting through one summer without melting.
The map below shows the age of sea ice across the Arctic for a week at the start of March. Red is the very old (5+ years) ice in the western Beaufort Sea, while dark blue is first year ice.
The bottom graph shows how the amount of ice of different ages has changed over time for that same week in March. Very old ice (red) is showing no signs of recovery, says NSIDC, with little change since the end of a strong five-year decline in 2012. The report says:
“The bottom line is that ice no longer survives in the Arctic for very long. It is lasting three to four years tops before melting or advecting out through Fram Strait. This is a big change from the past when much of the ice cover would survive upwards of a decade.”
Outlook for 2016
Scientists are quick to point out that while this year’s winter peak is at the low end of the scale, it doesn’t necessarily mean 2016 as a whole will break records for low ice cover.
How high or low ice cover reaches at the end of summer will depend a lot on when the melt season gets underway, how long it lasts and how other weather conditions conspire to strengthen or weaken the ice. But the fact that the ice is thin after a warm winter suggest it is starting on a vulnerable footing, Stroeve tells Carbon Brief:
“The Arctic is warmer than it used to be, the melt season starts earlier and ends later and all this helps to keep the summer ice cover low.”
YOU MIGHT ALSO LIKE
By Dana M Bergstrom, Euan Ritchie, Lesley Hughes and Michael Depledge
In 1992, 1,700 scientists warned that human beings and the natural world were "on a collision course." Seventeen years later, scientists described planetary boundaries within which humans and other life could have a "safe space to operate." These are environmental thresholds, such as the amount of carbon dioxide in the atmosphere and changes in land use.
The Good and Bad News<p><span>Ecosystems consist of living and non-living components, and their interactions. They work like a super-complex engine: when some components are removed or stop working, knock-on consequences can lead to system failure.</span></p><p>Our study is based on measured data and observations, not modeling or predictions for the future. Encouragingly, not all ecosystems we examined have collapsed across their entire range. We still have, for instance, some intact reefs on the Great Barrier Reef, especially in deeper waters. And northern Australia has some of the most intact and least-modified stretches of savanna woodlands on Earth.</p><p><span>Still, collapses are happening, including in regions critical for growing food. This includes the </span><a href="https://www.mdba.gov.au/importance-murray-darling-basin/where-basin" target="_blank" rel="noopener noreferrer">Murray-Darling Basin</a><span>, which covers around 14% of Australia's landmass. Its rivers and other freshwater systems support more than </span><a href="https://www.abs.gov.au/ausstats/[email protected]/latestproducts/94F2007584736094CA2574A50014B1B6?opendocument" target="_blank" rel="noopener noreferrer">30% of Australia's food</a><span> production.</span></p><p><span></span><span>The effects of floods, fires, heatwaves and storms do not stop at farm gates; they're felt equally in agricultural areas and natural ecosystems. We shouldn't forget how towns ran out of </span><a href="https://www.mdba.gov.au/issues-murray-darling-basin/drought#effects" target="_blank" rel="noopener noreferrer">drinking water</a><span> during the recent drought.</span></p><p><span></span><span>Drinking water is also at risk when ecosystems collapse in our water catchments. In Victoria, for example, the degradation of giant </span><a href="https://theconversation.com/logging-must-stop-in-melbournes-biggest-water-supply-catchment-106922" target="_blank" rel="noopener noreferrer">Mountain Ash forests</a><span> greatly reduces the amount of water flowing through the Thompson catchment, threatening nearly five million people's drinking water in Melbourne.</span></p><p>This is a dire <em data-redactor-tag="em">wake-up</em> call — not just a <em data-redactor-tag="em">warning</em>. Put bluntly, current changes across the continent, and their potential outcomes, pose an existential threat to our survival, and other life we share environments with.</p><p><span>In investigating patterns of collapse, we found most ecosystems experience multiple, concurrent pressures from both global climate change and regional human impacts (such as land clearing). Pressures are often </span><a href="https://besjournals.onlinelibrary.wiley.com/doi/abs/10.1111/1365-2664.13427" target="_blank" rel="noopener noreferrer">additive and extreme</a><span>.</span></p><p>Take the last 11 years in Western Australia as an example.</p><p>In the summer of 2010 and 2011, a <a href="https://theconversation.com/marine-heatwaves-are-getting-hotter-lasting-longer-and-doing-more-damage-95637" target="_blank" rel="noopener noreferrer">heatwave</a> spanning more than 300,000 square kilometers ravaged both marine and land ecosystems. The extreme heat devastated forests and woodlands, kelp forests, seagrass meadows and coral reefs. This catastrophe was followed by two cyclones.</p><p>A record-breaking, marine heatwave in late 2019 dealt a further blow. And another marine heatwave is predicted for <a href="https://www.theguardian.com/environment/2020/dec/24/wa-coastline-facing-marine-heatwave-in-early-2021-csiro-predicts" target="_blank" rel="noopener noreferrer">this April</a>.</p>
What to Do About It?<p><span>Our brains trust comprises 38 experts from 21 universities, CSIRO and the federal Department of Agriculture Water and Environment. Beyond quantifying and reporting more doom and gloom, we asked the question: what can be done?</span></p><p>We devised a simple but tractable scheme called the 3As:</p><ul><li>Awareness of what is important</li><li>Anticipation of what is coming down the line</li><li>Action to stop the pressures or deal with impacts.</li></ul><p>In our paper, we identify positive actions to help protect or restore ecosystems. Many are already happening. In some cases, ecosystems might be better left to recover by themselves, such as coral after a cyclone.</p><p>In other cases, active human intervention will be required – for example, placing artificial nesting boxes for Carnaby's black cockatoos in areas where old trees have been <a href="https://www.environment.gov.au/biodiversity/threatened/publications/factsheet-carnabys-black-cockatoo-calyptorhynchus-latirostris" target="_blank" rel="noopener noreferrer">removed</a>.</p><p><span>"Future-ready" actions are also vital. This includes reinstating </span><a href="https://www.abc.net.au/gardening/factsheets/a-burning-question-fire/12395700" target="_blank" rel="noopener noreferrer">cultural burning practices</a><span>, which have </span><a href="https://theconversation.com/australia-you-have-unfinished-business-its-time-to-let-our-fire-people-care-for-this-land-135196" target="_blank" rel="noopener noreferrer">multiple values and benefits for Aboriginal communities</a><span> and can help minimize the risk and strength of bushfires.</span></p><p>It might also include replanting banks along the Murray River with species better suited to <a href="https://www.abc.net.au/gardening/factsheets/my-garden-path---matt-hansen/12322978" target="_blank" rel="noopener noreferrer">warmer conditions</a>.</p><p>Some actions may be small and localized, but have substantial positive benefits.</p><p>For example, billions of migrating Bogong moths, the main summer food for critically endangered mountain pygmy possums, have not arrived in their typical numbers in Australian alpine regions in recent years. This was further exacerbated by the <a href="https://theconversation.com/six-million-hectares-of-threatened-species-habitat-up-in-smoke-129438" target="_blank" rel="noopener noreferrer">2019-20</a> fires. Brilliantly, <a href="https://www.zoo.org.au/" target="_blank" rel="noopener noreferrer">Zoos Victoria</a> anticipated this pressure and developed supplementary food — <a href="https://theconversation.com/looks-like-an-anzac-biscuit-tastes-like-a-protein-bar-bogong-bikkies-help-mountain-pygmy-possums-after-fire-131045" target="_blank" rel="noopener noreferrer">Bogong bikkies</a>.</p><p><span>Other more challenging, global or large-scale actions must address the </span><a href="https://www.youtube.com/watch?v=iICpI9H0GkU&t=34s" target="_blank" rel="noopener noreferrer">root cause of environmental threats</a><span>, such as </span><a href="https://www.nature.com/articles/s41559-018-0504-8" target="_blank" rel="noopener noreferrer">human population growth and per-capita consumption</a><span> of environmental resources.</span><br></p><p>We must rapidly reduce greenhouse gas emissions to net-zero, remove or suppress invasive species such as <a href="https://onlinelibrary.wiley.com/doi/abs/10.1111/mam.12080" target="_blank" rel="noopener noreferrer">feral cats</a> and <a href="https://theconversation.com/the-buffel-kerfuffle-how-one-species-quietly-destroys-native-wildlife-and-cultural-sites-in-arid-australia-149456" target="_blank" rel="noopener noreferrer">buffel grass</a>, and stop widespread <a href="https://theconversation.com/to-reduce-fire-risk-and-meet-climate-targets-over-300-scientists-call-for-stronger-land-clearing-laws-113172" target="_blank" rel="noopener noreferrer">land clearing</a> and other forms of habitat destruction.</p>
Our Lives Depend On It<p>The multiple ecosystem collapses we have documented in Australia are a harbinger for <a href="https://www.iucn.org/news/protected-areas/202102/natures-future-our-future-world-speaks" target="_blank">environments globally</a>.</p><p>The simplicity of the 3As is to show people <em>can</em> do something positive, either at the local level of a landcare group, or at the level of government departments and conservation agencies.</p><p>Our lives and those of our <a href="https://theconversation.com/children-are-our-future-and-the-planets-heres-how-you-can-teach-them-to-take-care-of-it-113759" target="_blank">children</a>, as well as our <a href="https://theconversation.com/taking-care-of-business-the-private-sector-is-waking-up-to-natures-value-153786" target="_blank" rel="noopener noreferrer">economies</a>, societies and <a href="https://theconversation.com/to-address-the-ecological-crisis-aboriginal-peoples-must-be-restored-as-custodians-of-country-108594" target="_blank" rel="noopener noreferrer">cultures</a>, depend on it.</p><p>We simply cannot afford any further delay.</p><p><em><a rel="noopener noreferrer" href="https://theconversation.com/profiles/dana-m-bergstrom-1008495" target="_blank" style="">Dana M Bergstrom</a> is a principal research scientist at the University of Wollongong. <a rel="noopener noreferrer" href="https://theconversation.com/profiles/euan-ritchie-735" target="_blank" style="">Euan Ritchie</a> is a professor in Wildlife Ecology and Conservation, Centre for Integrative Ecology, School of Life & Environmental Sciences at Deakin University. <a rel="noopener noreferrer" href="https://theconversation.com/profiles/lesley-hughes-5823" target="_blank">Lesley Hughes</a> is a professor at the Department of Biological Sciences at Macquarie University. <a rel="noopener noreferrer" href="https://theconversation.com/profiles/michael-depledge-114659" target="_blank">Michael Depledge</a> is a professor and chair, Environment and Human Health, at the University of Exeter. </em></p><p><em>Disclosure statements: Dana Bergstrom works for the Australian Antarctic Division and is a Visiting Fellow at the University of Wollongong. Her research including fieldwork on Macquarie Island and in Antarctica was supported by the Australian Antarctic Division.</em></p><p><em>Euan Ritchie receives funding from the Australian Research Council, The Australia and Pacific Science Foundation, Australian Geographic, Parks Victoria, Department of Environment, Land, Water and Planning, and the Bushfire and Natural Hazards CRC. Euan Ritchie is a Director (Media Working Group) of the Ecological Society of Australia, and a member of the Australian Mammal Society.</em></p><p><em>Lesley Hughes receives funding from the Australian Research Council. She is a Councillor with the Climate Council of Australia, a member of the Wentworth Group of Concerned Scientists and a Director of WWF-Australia.</em></p><p><em>Michael Depledge does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</em></p><p><em>Reposted with permission from <a href="https://theconversation.com/existential-threat-to-our-survival-see-the-19-australian-ecosystems-already-collapsing-154077" target="_blank" style="">The Conversation</a>. </em></p>
- Coral Reef Tipping Point: 'Near-Annual' Bleaching May Occur ... ›
- Scientists Warn Humanity in Denial of Looming 'Collapse of ... ›
EcoWatch Daily Newsletter
To save the planet, we must save the Amazon rainforest. To save the rainforest, we must save its indigenous peoples. And to do that, we must demarcate their land.
A new EarthxTV film special calls for the protection of the Amazon rainforest and the indigenous people that call it home. EarthxTV.org
- Meet the 'Women Warriors' Protecting the Amazon Forest - EcoWatch ›
- Indigenous Tribes Are Using Drones to Protect the Amazon ... ›
- Amazon Rainforest Will Collapse by 2064, New Study Predicts ... ›
- Deforestation in Amazon Skyrockets to 12-Year High Under Bolsonaro ›
- Amazon Rainforest on the Brink of Turning Into a Net Carbon Emitter ... ›
By Anke Rasper
"Today's interim report from the UNFCCC is a red alert for our planet," said UN Secretary General Antonio Guterres.
The report, released Friday, looks at the national climate efforts of 75 states that have already submitted their updated "nationally determined contributions," or NDCs. The countries included in the report are responsible for about 30% of the world's global greenhouse gas emissions.
- World Leaders Fall Short of Meeting Paris Agreement Goal - EcoWatch ›
- UN Climate Change Conference COP26 Delayed to November ... ›
- 5 Years After Paris: How Countries' Climate Policies Match up to ... ›
- Biden Win Puts World 'Within Striking Distance' of 1.5 C Paris Goal ... ›
- Biden Reaffirms Commitment to Rejoining Paris Agreement ... ›
India's New Delhi has been called the "world air pollution capital" for its high concentrations of particulate matter that make it harder for its residents to breathe and see. But one thing has puzzled scientists, according to The Guardian. Why does New Delhi see more blinding smogs than other polluted Asian cities, such as Beijing?
- This Indian Startup Turns Polluted Air Into Climate-Friendly Tiles ... ›
- How to Win the Fight Against Plastic - EcoWatch ›
In a historic move, the Delaware River Basin Commission (DRBC) voted Thursday to ban hydraulic fracking in the region. The ban was supported by all four basin states — New Jersey, Delaware, Pennsylvania and New York — putting a permanent end to hydraulic fracking for natural gas along the 13,539-square-mile basin, The Philadelphia Inquirer reported.
- Appalachian Fracking Boom Was a Jobs Bust, Finds New Report ... ›
- Long-Awaited EPA Study Says Fracking Pollutes Drinking Water ... ›
- Pennsylvania Fracking Water Contamination Much Higher Than ... ›