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A brief bout of bad air in Scotland

July 3, 2024 By EarthWise Leave a Comment

Scotland, and the UK in general, used to suffer from sulfur dioxide pollution. Industrial and domestic emissions, especially from burning coal, contributed heavily to urban air leading to the London smog of the 1950s and the acid rain of the 1980s. But national air pollution agreements and various international measures have been highly successful in reducing sulfur dioxide emissions. Desulfurization of coal-fired powerplants and the introduction of ultralow sulfur fuels among other measures have decreased sulfur dioxide emission by 98% since 1970.

As a result, it came as quite a surprise on May 31st when Edinburgh saw sulfur dioxide levels higher than had been observed in over 30 years. The levels greatly exceeded air quality objectives for 10 hours with concentrations even creeping towards workplace exposure limits.

What happened? For once, it was nothing that people did. Two days earlier, a volcanic fissure eruption took place in the Reykjanes Peninsula in Iceland, some 850 miles from Edinburgh. Because of an unusual meteorological configuration, the prevailing winds sent the plume of volcanic gases southward towards Scotland. Had the eruption taken place 60 miles further north or happened a few hours later, the plume of gases would have missed the UK entirely and would have traveled north to the Arctic region.

Icelandic volcanic eruptions have impacted air travel in Europe on a number of occasions. This non-explosive eruption had little impact outside of its local region, but it turned out to briefly wreak havoc in Scotland. Fortunately, this pollution event was short-lived.

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Atmospheric sulphur dioxide levels reach historic high in Scotland following Icelandic volcano eruption

Photo, posted November 17, 2021, courtesy of Catherine Poh Huay Tan via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Wildfires And Air Quality | Earth Wise

October 26, 2023 By EarthWise Leave a Comment

People in the Northeast have been dealing with unhealthy air quality in recent times because of smoke from hundreds of wildfires in Canada. Canada has experienced a much higher than average incidence of blazes this year with nearly 500 fires burning uncontrolled at times.

It turns out that states far away from Canada aren’t necessarily free from the impact of the fires. Early in October, smoke from a wildfire burning in Quebec made its way south all the way down to Florida and created unhealthy air quality and reduced visibility across much of the state. Smoke from the same fire had created hazy air in Boston, New York City, and parts of Connecticut before heading south.

It took a rather unusual set of atmospheric conditions to make this happen. The smoke drifted from Canada into the western Atlantic. From there, it got trapped behind a cold front and was then pushed south along the east coast until it finally moved inland across Florida.

Wildfires produce a variety of particles and gases from the burning of vegetation such as organic carbon, black carbon, nitrogen oxides, carbon monoxide and hazardous air pollutants. The mixture of particles and gases in wildfire smoke is associated with respiratory symptoms like shortness of breath and reduced lung function, as well as dangerous cardiovascular effects.

Smoke from increasingly frequent and increasingly large fires has started to undo decades of gains in air quality brought about by air pollution policies. According to researchers, wildfires in the United States in recent years have undone about 25% of past progress in cleaning up air pollution in states from coast to coast.

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Wildfire Smoke From Canada Creates Unhealthy Air Quality in Florida

Photo, posted June 8, 2023, courtesy of Anthony Quintano via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Clean Energy From North Africa | Earth Wise

April 7, 2023 By EarthWise Leave a Comment

Europe is hungry for clean energy. The war in Ukraine has amplified Europe’s desire to end its reliance on Russian natural gas. Increasingly, Europe is pushing to install giant solar energy farms in sunny North Africa and transport the energy through underwater cables.

Solar panels in sunny North Africa generate up to three times more energy than those in Europe. As a result, solar farms and wind farms as well are proliferating south of the Mediterranean Sea. Morocco’s Noor and Egypt’s Benban solar farms are among the largest in the world. Many of these farms were initially built to boost domestic power supplies and reduce dependence on coal. But now these farms are increasingly supplying green energy to industrial neighbors in Europe.

Morocco has signed deals with the European Union to expand power exports. Egypt is considering proposals for cables to link to Greece. Another planned cable would link new solar farms in Tunisia to Italy’s grid. These projects would certainly bring money and jobs to North African countries, but it isn’t all good news.

There are growing concerns about the environmental impacts of Europe outsourcing its energy needs. Desert ecosystems could be greatly compromised. And much of this development is likely to happen with only minimal community consultation or ecological assessment. Half of Africa’s population does not have access to reliable power grids. Electricity becoming a major export is not likely to improve this situation.

Europe has long obtained many resources from the developing world. Now it is tapping into the sunshine and wind in other lands. It remains to be seen if North Africa’s countries will achieve the large potential gains those resources can offer them.

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In Scramble for Clean Energy, Europe Is Turning to North Africa

Photo, posted October 17, 2019, courtesy of Richard Allaway via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

River Of Dust | Earth Wise

April 25, 2022 By EarthWise Leave a Comment

Every year, more than 100 million tons of dust blow out of North Africa. Strong seasonal winds lift the dust from the Sahara Desert northward. A few times a year, the winds from the south are strong and persistent enough to drive the dust all the way to Europe.

On March 15, a large plume of Saharan dust blew out of North Africa and crossed the Mediterranean into Western Europe. European cities were blanketed with the dust, degrading their air quality, and turning skies orange. Alpine ski slopes were stained with the dust.

These dust events are associated with so-called atmospheric rivers that arise from storms. Such rivers usually bring extreme moisture but can also carry dust. Over the past 40 years, nearly 80% of atmospheric rivers over northwestern Africa have led to extreme dust events over Europe. The March 15 event was associated with Storm Celia, a powerful system that brought strong winds, rain, sleet, hail, and snow to the Canary Islands.

Atmospheric dust plays a major role in climate and biological systems. The dust absorbs and reflects solar energy and also fertilizes ocean ecosystems with iron and other minerals.

The climate effects of dust are complicated. Dust can decrease the amount of sunlight reaching the surface, affect cloud formation, and decrease temperatures. But dust also darkens the snowpack, leading to more rapid snowmelt. A 2021 dust event resulted in a rapid melt of Alpine snow, reducing its depth by half in less than a month.

The effects of this year’s dust event are not yet known, but this atmospheric river associated with Storm Celia appeared to carry less water and more dust compared with the 2021 event.

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An Atmospheric River of Dust

Photo, posted December 2, 2019, courtesy of Catherine Poh Huay Tan via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Coastal Northeast Is A Hotspot | Earth Wise

November 16, 2021 By EarthWise Leave a Comment

Global warming is, obviously, a world-wide phenomenon. When the concept of a 2 degrees Celsius temperature rise is discussed, it refers to the average global temperature and the effects that would have on such things as sea level rise and weather patterns. But the effects of the changing climate are not homogeneous. Very different things can happen and are happening in different places.

One such place is the coastal northeastern United States, which is a global warming hotspot. The region is heating faster than most regions of North America and, indeed, 2 degrees of summer warming has already happened in the Northeast.

New research led by the University of Massachusetts Amherst has determined that this heating is linked to significant alterations in the ocean and atmospheric conditions over the North Atlantic.

Several studies have found that the Atlantic Meridional Circulation is slowing down. The AMOC conveys warm, salty water from the tropics north towards Greenland, where it cools and sinks. The cooled water than flows back south as deep-water currents. As the warming climate melts glaciers in Greenland, the circulation slows down, less cooled water arrives in the south, and there is more heating of the ocean off the Northeastern coast.

At the same time, the North Atlantic Oscillation, a weather phenomenon that governs the strength and position of the winds that blow from the U.S. over the Atlantic, has tended to settle into a pattern that enhances the influence of ocean air on the eastern seaboard climate. Warmer ocean air being blown over the region has led to rising temperatures in Boston, New York, and Providence, Rhode Island.

As the average temperature of the world rises, some places will warm more quickly and others more slowly.

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The Coastal Northeastern U.S. Is A Global Warming Hotspot

Photo, posted August 8, 2010, courtesy of Doug Kerr via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Expensive And Dangerous Storms | Earth Wise

August 7, 2020 By EarthWise Leave a Comment

Severe storms are getting more and more common. Early in July, the United States experienced its 10th billion-dollar weather disaster of the year – the earliest this has happened. It also marks 2020 as the sixth consecutive year with at least 10 such extreme weather events, which is also a record. With the country struggling with the effects of a global pandemic, extreme weather is pretty much the last thing we need.

This year’s 10 storms have primarily consisted of tornadoes, damaging winds, and hail. Seven out of the 10 storms were in the South or Southeast. An Easter Sunday outbreak in that region saw 190 tornadoes and 36 people were killed that day.

Since 1980, the US has averaged nearly 7 billion-dollar weather disasters per year. But the last five years have seen nearly 14 severe storms on average. The way things are going this year, there will probably be more than that number.

This year’s growing total does not include the looming hurricane season, which is widely predicted to be more active than usual. Because so many places in the South are still recovering from earlier disasters, they are particularly vulnerable to the effects of an active hurricane season.

Meanwhile, much of the country is suffering from drought conditions, making wildfires a major concern. Recent years have seen deadly and destructive wildfires in many places, notably in California two years ago. Between hurricanes and wildfires, the prospects are alarming for what could turn out to be a disastrous year for expensive and dangerous severe weather.

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US hits 10th billion-dollar weather disaster of the year — at a record pace

Photo, posted March 3, 2020, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

American Robins And Climate Change | Earth Wise

April 30, 2020 By EarthWise Leave a Comment

American robins are migratory songbirds that can be found throughout much of North America. Named after European robins because of their reddish-orange breast, American robins are often found hopping across lawns and nesting on porches. Their rich caroling is among the first pre-dawn bird songs heard in spring and summer.

While some overwinter in northern parts of the United States and southern Canada, most American robins migrate south to overwinter in places like Florida and the Gulf Coast, as well as central Mexico and the Pacific Coast. They typically head south by the end of August and return north sometime between February and March to their breeding grounds in Canada and Alaska. They spend their short time there trying to find a mate, build a nest, raise a family, and consume enough food to sustain themselves on their long return journey south.

But climate change is making these seasonal rhythms less predictable. According to a new study recently published in the journal Environmental Research Letters, American robin migration is kicking off earlier by about five days each decade. The birds now migrate 12 days earlier than they did in 1994.

For 25 years, researchers at Canada’s Slave Lake have been recording the timing of American robin spring migration. They attached GPS devices to 55 robins, tracking their movements from April through June. The researchers linked the birds’ movement with weather data, including air temperature, snow depth, wind speed, and precipitation. The results showed that robins start migrating north earlier when winters are warm and dry.

Understanding the influence over the timing of migratory events is important because the timing of migration can influence reproductive success.

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A Migration Mystery

American robins now migrate 12 days earlier than in 1994

Photo, posted January 1, 2020, courtesy of Becky Matsubara via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Other Ways To Cut Vehicle Emissions

October 17, 2019 By EarthWise Leave a Comment

It is pretty clear that the way to drastically reduce vehicle greenhouse gas emissions is to switch as many vehicles as possible to electric power. As a result, more and more localities are putting in place policies that encourage electrification.

While there is no doubt that electrification is the long-term solution to vehicle emissions, a recent study by MIT and the Ford Motor Company found that, in the short term, there are some places in the US where electric cars are not the best way to reduce emissions.

The study looked at a variety of factors that affect the relative performance of vehicles. These include the role of low temperatures in reducing battery performance, regional differences in the average number of miles driven annually, and significant differences in the way electricity is generated in different parts of the US.

The results showed that electric vehicles definitely provide the greatest impact in reducing greenhouse gas emissions for most of the country – and particularly on both coasts and in the south – but that there are some places in the upper Midwest where the greatest reduction would be achieved by the use of lightweight gasoline-powered vehicles.

In places like parts of Wisconsin and Michigan, it is mostly rural, there are cold winters, and electricity is predominantly generated by coal-powered plants. In these places, if gas-powered lightweight cars were to be used, the overall benefit would be greater than that of electric cars. Unfortunately, there are no high-volume lightweight gasoline-powered mid-sized cars on the market in the US. Ironically, the only cars of that class using lightweight aluminum construction are Teslas.

While electric cars are truly the long-term solution, the study does demonstrate the benefits of reducing the weight of vehicles.

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What’s the best way to cut vehicle greenhouse-gas emissions?

Photo, posted February 9, 2018, courtesy of Dave Field via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Refugee Corals

August 30, 2019 By EarthWise Leave a Comment

As climate change warms the ocean, subtropical environments are becoming more favorable for corals than the equatorial waters where they traditionally thrived. As a result, drifting coral larvae are settling and growing in new regions.

According to new research in the journal Marine Ecology Progress Series, the number of young corals on tropical reefs has declined by 85% over the past 40 years. At the same time, the numbers on subtropical reefs has doubled.

Only certain types of coral can reach these new subtropical locations. That depends on how far the microscopic larvae can swim and drift on currents before they exhaust their limited fat stores. Thus, the reef ecosystems that develop have new blends of species that have previously never coexisted. It is not clear how long it will take for the new systems to reach equilibrium.

Coral reefs are complicated systems that depend on the interplay between species to enable their healthy functioning. Apart from the corals themselves, there are the coraline algae that symbiotically coexist with them. How all of this will play out in these evolving ecosystems is unknown.

In the meantime, the research has found that these refugee corals are settling at latitudes up to 35 degrees both north and south of the equator. It is no longer so clear what constitute native species in the reefs. It remains to be seen whether new reefs in subtropical oceans can support the incredible biodiversity seen in tropical reefs. But ultimately, these changing ecosystems could potentially bring new resources and opportunities, such as fishing and tourism, to places where they never existed before.

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Coral Reefs Shifting Away from Equatorial Waters

Photo, posted March 22, 2011, courtesy of Simone Lovati via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Climate Change And The Polar Vortex

February 20, 2019 By EarthWise Leave a Comment

This winter has seen some brutally-cold weather in many places, some of it record-breaking. Predictably, some climate-change deniers point to this as evidence that the climate is not warming at all. They are quite wrong.

For starters, it is essential to understand the difference between climate and weather. Climate is the average weather patterns in a region over extended periods of time. Weather is the short-term fluctuations in temperature, precipitation, barometric pressure, wind, and so forth. There can be extremes in weather of many types in a given climate region including very cold weather in a warming climate.

The recent cold weather events in the U.S. stem from the flow of Arctic air into southern regions. Such flows are impacted dramatically by the behavior of the jet stream. These high-altitude east-to-west winds are driven by temperature differences between cold arctic air and warm tropical air and play a huge role in our weather.

The Arctic has seen extremely unusual warming due to the changing climate, weakening and fracturing the polar vortex, which is a persistent low-pressure area near the pole. The changing air flow from the Arctic causes the jet stream to take wild swings. When it swings further south, it causes cold air to reach farther south. These swings tend to hang around for a while, leading to extended periods of cold weather in the winter and, actually, extended periods of warm weather or even droughts in the summer. Studies have predicted that extreme, deadly weather events could increase by as much as fifty percent by 2100.

As more Arctic air flows into southern regions, North America can expect to see harsher winters. The warming climate doesn’t always lead to warmer weather.

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