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Messages - azharul.esdm

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You may have heard about the hole in the ozone layer, which hovers over Antarctica. It has shrunk over time thanks to policies that curbed the use of ozone-depleting chemicals. In the nearly 40 years that NASA has kept track, it has never been smaller. That's the good news.

The bad news is that a separate hole in the ozone layer briefly opened up in the Arctic in March before closing in April, and climate change may be partly to blame.

This isn't the first such rift to develop in the Arctic, but it is the largest. Scientists say that in March, a stratospheric polar vortex — a band of strong, frigid winds circling the pole — corralled chlorine and bromine that chewed away at the ozone layer. Scientists said that climate change may have set the stage for a colder, and thus more powerful, polar vortex.

"In those years when a vortex can spin and set itself up and be undisturbed, it's getting colder and colder," said Ross Salawitch, a climate scientist at the University of Maryland. Cold air strengthens polar vortexes, allowing them to deal more damage to the ozone layer, he said.

This year's Arctic polar vortex was unusually strong and long-lived, helping to deplete the ozone layer. At the same time, currents that would normally deliver ozone from surrounding areas were stagnant. The bruising was far less severe than what is typically seen over the South Pole, though. At the South Pole, stratospheric polar vortexes are reliably strong thanks to the extreme cold, so the ozone layer regularly thins.

In a stratospheric polar vortex, high-altitude clouds form from trace gasses in the atmosphere. Pollutants containing chlorine and bromine are essentially benign until they run into one of these clouds. Then they transform into chemicals capable of terrorizing the ozone layer.

They still need sunlight to do their dirty work, however. That comes at the start of spring —around September in the Southern Hemisphere and around March in the Northern Hemisphere. As the days get longer, these chemicals react with sunlight to deplete stratospheric ozone.

Because Antarctica is so isolated from the rest of the world, a strong polar vortex can form undisturbed. That's not the case in the Arctic, where the mix of land and water surrounding the North Pole produces more dynamic weather that can weaken or disrupt a polar vortex.


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Geography & Environment / Arctic Sea Ice
« on: May 28, 2020, 09:19:03 PM »
Please click the link below:
http://nsidc.org/arcticseaicenews/

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Thanks to all for your valuable comment.

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Environmental Science and Disaster Management / Re: Sahara is growing
« on: April 26, 2018, 12:39:26 AM »
Interesting information.

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A major shift in western Arctic wind patterns occurred throughout the winter of 2017 and the resulting changes in sea ice movement are possible indicators of a changing climate, says Kent Moore, a professor of physics at the University of Toronto Mississauga.

Thanks to data collected by buoys dropped from aircraft onto the Arctic Ocean's sea ice, Moore and colleagues at the University of Washington, where he spent the year as the Fulbright Visiting Chair in Arctic Studies, were able to observe this marked, anomalous shift in Arctic wind patterns and sea ice movement during the winter of 2017.

Their study is published in Geophysical Research Letters.

Usually, the western Arctic has relatively stable weather during the winter; it is home to a quasi-stationary region of high pressure known as the Beaufort High, which promotes "anti-cyclonic" winds that travel in a clockwise direction and move sea ice along with it. By contrast, the eastern Arctic has a more dynamic climate where cyclones are a common winter phenomenon with storms moving from Greenland towards Norway and the Barents Sea.

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Dangerous levels of air pollution in towns and cities across the north of England are threatening the health of hundreds of thousands of people and stifling economic growth, according to a new report.

The analysis by the Institute for Public Policy Research (IPPR) North describes air pollution as “the tobacco of the 21st century” and says that while there has been a growing concern about the problem in London, many residents in regional towns and cities are unaware of the threat to their health.

Darren Baxter, researcher at IPPR North, said it was time the government took radical action.


Guardian Today: the headlines, the analysis, the debate - sent direct to you
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“Too often the attention focuses on unclean air in the capital, but the reality is that it’s poisoning thousands in our regional cities too,” said Baxter. “Michael Gove [the new environment secretary] must show that the government is not prepared to sit on its hands while up to 40,000 people are killed every year from dirty air. We need to see radical plans to ditch diesel, introduce incentives for electric cars and bring in clean air zones in our major cities.”

The government has suffered two legal defeats over its plans to improve air quality in the UK after judges ruled they were so poor as to be unlawful. The courts have given ministers until 31 July to publish a new plan.

Campaigners want Gove to introduce a range of measures including charging clean air zones in the worst hit areas and a diesel scrappage scheme to compensate drivers who bought diesel cars after being told they were better for the environment.

The government’s own figures show that although London has by far the highest level of nitrogen dioxide (NO2) pollution, many urban areas – including large swaths of the Midlands, the north-west, West Yorkshire and the northeast – suffer dangerous levels of pollution.

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Last year, the European Space Agency launched the Trace Gas Orbiter to Mars. It is designed to look for methane – a key tracer of life – to determine if Martian microbes are present on the red planet.

Now, ESA is preparing to launch another spacecraft to look at methane on another planet: our own.

The UK-built Sentinel-5P, a pollution monitoring satellite, is ready to begin its journey from Airbus Defence and Space, Stevenage, to the Plesetsk Cosmodrome, Russia, where it will lift off in late September/early October.

Sentinel-5P is part of the Copernicus global monitoring programme, a joint venture between the European Commission and the European Space Agency. This particular spacecraft is the first Copernicus satellite dedicated to monitoring atmospheric chemistry.

Missions like this are essential for making the connection between space and everyday life on Earth, according to Colin Paynter, Managing Director of Airbus Defence and Space, UK. He says, “Space is not just for geeks, it is part of our national and international infrastructure.”

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The Environmental Protection Agency’s new administrator, Scott Pruitt, has called for a “back-to-basics” or “originalist” approach to the agency. It is unclear what he means, but in a 22 May memo he said he would prioritize the EPA’s program that handles heavily contaminated waste areas, known as “Superfund sites”.

In the memo, Pruitt heralds that under his administration, “Superfund and the EPA’s land and water cleanup efforts will be restored to their rightful place at the center of the agency’s core mission”.


Trump's alarming environmental rollback: what's been scrapped so far
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For Pruitt, the primary role of the EPA is janitorial: using taxpayer money to clean up after polluting industries. But that is neither how the EPA was originally envisaged, nor how the Superfund program was conceived.

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You would think that ending a traffic restriction would improve journey times, but the sudden termination of Jakarta’s high-occupancy vehicle (HOV) lanes had the opposite effect. To use these lanes drivers required two passengers, but a trade in hiring people bought the lanes to an abrupt end last year. The traffic could spread across all lanes, but journey times and congestion increased. In fact, traffic worsened over the whole network almost immediately. Even on roads with no HOV lanes, at times when the lanes had not operated, delays increased by up to two minutes per km. The US embassy measures air quality from its roof in Jakarta. It is too early to see the changes, but we can be sure that it did not get better.

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US scientists have calculated the total amount of plastic ever made and put the number at 8.3 billion tonnes.
It is an astonishing mass of material that has essentially been created only in the last 65 years or so.
The 8.3 billion tonnes is as heavy as 25,000 Empire State Buildings in New York, or a billion elephants.
The great issue is that plastic items, like packaging, tend to be used for very short periods before being discarded.
More than 70% of the total production is now in waste streams, sent largely to landfill - although too much of it just litters the wider environment, including the oceans.
"We are rapidly heading towards 'Planet Plastic', and if we don't want to live on that kind of world then we may have to rethink how we use some materials, in particular plastic," Dr Roland Geyer told BBC News.

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In tea country around Sylhet, conditions for workers such as Bina – descendants of labourers imported by the British during the 19th century from what is now India – have long been as wretched as the landscape is enchanting.

The estates are the only world they know, run by managers overseeing business from hilltop, British-era bungalows in semi-feudal operations that have changed little since colonial days.


Bangladesh struggles to turn the tide on climate change as sea levels rise
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Isolated by geography, as well as by their Hindu culture in the predominantly Muslim country, Bangladesh’s tea pickers are among the most excluded and marginalised communities, earning 85 taka (barely $1) for a day of back-breaking work.
Look at the following link for further information.
https://www.theguardian.com/global-development/2017/mar/14/clean-water-finally-flows-to-transform-lives-tea-pickers-bangladesh-surma-valley

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