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Ice-free Arctic summers likely by 2050, even with climate action: study – The Independent Barents Observer

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By Levon Sevunts 

The study, Arctic Sea Ice in CMIP6,  published in Geophysical Research Letters analyzed recent results from 40 different climate models.

Using these models, scientists from 21 research institutes from around the world assessed the evolution of Arctic sea-ice cover in a scenario with high CO2 emissions and little climate protection.

As expected, summer Arctic sea-ice disappeared quickly in these simulations.

However, some of these models also showed that the ice still disappeared even in some simulations where CO2 emissions were rapidly reduced.

“The key point is that we have now reached a point that whether we are very aggressive in cutting our emissions or whether we go business as usual, we will be seeing years without any ice in the Arctic Ocean in the summer,” said study co-author Bruno Tremblay, associate professor in the Department of Atmospheric and Oceanic Sciences at McGill University.

What will change between different scenarios is the frequency at which this phenomenon occurs, Tremblay added.

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“If we go business as usual, it will be a much more frequent occurrence, it will be pretty much always the case starting in 2030, 2035 or 2040,” Trembleay told Radio Canada International in an interview from Toulouse, France, where he is on sabbatical.

“If we do severe cuts to our CO2 emissions, it will be an occurrence that happens once in a while but it will still occur.”

An ice-free Arctic 

Photo: Thomas Nilsen

Each summer, the area of sea-ice coverage decreases and grows again in winter.

However, since researchers began keeping satellite records in 1979, summer Arctic ice has lost 40 per cent of its area and up to 70 per cent of its volume.

The entire Arctic Ocean, the smallest and the shallowest of world oceans, covers an area of about 14.06 million square kilometres.

Scientists define an ice-free Arctic as one in which the Arctic Ocean sea ice covers an area of about 1 million square kilometres or less, Tremblay said.

“When you have 1 million square kilometres of ice left, you have a thin, narrow band of ice left in the north of the Canadian Arctic Archipelago and some ice left within the archipelago but basically the entire Arctic Ocean is free of ice except for that very localized region,” Tremblay said.

The ice-free season is also expected to get substantially longer, he added.

“Ice always comes back in the winter but it will come back later and later, because as you have less and less ice, more solar light is absorbed in the surface ocean, it takes longer in the fall before you ventilate all this heat into the atmosphere,” Tremblay said.

“And so gradually October becomes ice-free as well, August as well, not just September, and then November-December becomes ice-free and June as well, so the ice-free season becomes wider and wider.”

Affecting Arctic ecosystems 

Walruses on the ice in the Hinlopen Strait between Spitsbergen and Nordaustlandet on Svalbard. Photo: Thomas Nilsen

This will substantially affect the Arctic ecosystem and climate, particularly ice-dependent species such as polar bears and seals, Tremblay said.

“This will mean for them a longer and longer period without ice, which basically means fasting,” Tremblay said.

“For polar bears it means staying on land and they will have to wait until the end of October, November and then finally December before they can return and hunt [on the ice],” Tremblay said.

Female polar bears give birth to cubs in January and February and then go on the ice in May to hunt seals and fatten up until the ice-free season comes and they have to fast, he said.

With the ice-free season coming earlier and lasting longer, this means polar bears will have to fast for much longer.

Research in the Western Hudson Bay in the southern part of the Canadian Arctic shows that the average fasting time for polar bears in the area has gone from 107 days in the 1980s to 130 days in the early 2000s.

As a result, the Western Hudson Bay polar bear population is estimated to have dropped by 30 per cent since the 1980s. Other polar bear populations further north in the Canadian Arctic are stable or even growing. However, that could change with the warming climate.

“We’re seeing in the Hudson Bay now is what we will be seeing the Arctic Ocean in a decade or two,” Tremblay said.

The models looking even further into the future into 2100 and 2200 predict an ice free Arctic even in the winter, Tremblay said.

However, as the Arctic sea-ice extent decreases during this transition to an ice-free Arctic, the year-to-year variability in extent is expected to greatly increase, Tremblay said.

The last time the Earth experienced conditions like these was about 6,000 years ago at the end of the last glacial period when the solar insulation was much higher than it is now, Tremblay said.

“And what we’re going to see at the end of the century, you’re going to have to go back even further back, like hundreds of thousands of years, millions of years back when you saw conditions that warm,” Tremblay said.


This story is posted on Independent Barents Observer as part of Eye on the Arctic, a collaborative partnership between public and private circumpolar media organizations.

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What to expect from the ECB today [Video] – FXStreet

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– Overview of market sentiment at the European open (00:00).

– Detailed look at what to expect from the ECB announcement today (2:22).

– Merkel over delivers on the latest German stimulus package (17:40).

– Oil volatility here to stay as OPEC+ meeting looms (19:17).

– UK hits out at China over HK security law as they look for 5G alternatives (26:18).

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The cleanest pocket of air on Earth? It's in the Southern Ocean, between Tasmania and Antarctica – National Post

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The cleanest air on Earth lies in a pocket of sky between Tasmania and Antarctica, scientists say. 

A team of researchers at Colorado State University conducted a bioaerosol study of the Southern Ocean from Tasmania to Antarctica — the first of its kind — and drew air samples at the marine boundary level, where the atmosphere meets the ocean surface. 

“We were able to use the bacteria in the air over the Southern Ocean (SO) as a diagnostic tool to infer key properties of the lower atmosphere,” microbian ecologist Thomas Hill, from Colorado State University, told Science Alert.

Via modelling and analysis, the team noted that the samples were free of aerosol particles — a sure indicator of human activity, like fossil fuel burning, agriculture and fertilizer production — blown in from other parts of the world. The samples were also split into latitudinal zones, so that the team could observe how the air changed as they moved further south. 


Kathryn Moore collects bioaerosol samples in the Southern Ocean.

Kendall Sherrin/CSU

Via wind patterns, airborne microorganisms can travel vast distances. However, the bacterial make-up of the samples suggested that the closer they were taken to Antarctica, the cleaner they became. This suggests that aerosols from distant land masses and human activities are not travelling south into Antarctic air.

Instead, the samples appear to be composed of microorganisms from the ocean and little else. 

“It suggests that the SO (Southern Ocean) is one of very few places on Earth that has been minimally affected by anthropogenic activities,” Hill said. 

The results counter similar studies that were carried out in oceans in the subtropics and the Northern Hemisphere, which concluded that most microbes came from upwind continents.

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The Strawberry Moon Eclipse May Be Visible Over Metro Vancouver This Week – 604 Now

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Metro Vancouver is in for a treat this week, as we’ll be able to see the Strawberry Moon eclipse shine over the city this Friday.

Named after the red summer fruit, this phenomenon is June’s full moon – or otherwise called the Hot Moon or Rose moon.

RELATED: Vancouver Shoots Down Motion To Allow Drinking in Public Areas

This particular moon, however, kicks off 2020’s “eclipse season,” and will be visible during the moonrise and moonset. 

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You’ll just have to be ready at either 5:30 am or 8 pm, Friday, to see the eclipse over Metro Vancouver. 

So, will you be checking it out this week? 

Friday, June 5th is also the day of the second George Floyd protest, happening downtown.

For more Vancouver stories, head to our News section.

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