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Engineers can build a low-carbon world if we let them

Engineers can build a low-carbon world if we let them – opinion – 26 September 2011 – New Scientist.

The engineering solutions to combat climate change already exist. Politicians must be brave enough to use them before it’s too late

One word sums up the attitude of engineers towards climate change: frustration. Political inertia following the high-profile failure of 2009’s Copenhagen climate conference has coupled with a chorus of criticism from a vocal minority of climate-change sceptics. Add the current economic challenges and the picture looks bleak. Our planet is warming and we are doing woefully little to prevent it getting worse.

Engineers know there is so much more that we could do. While the world’s politicians have been locked in predominantly fruitless talks, engineers have been developing the technologies we need to bring down emissions and help create a more stable future.

Wind, wave and solar power, zero-emissions transport, low-carbon buildings and energy-efficiency technologies have all been shown feasible. To be rolled out on a global scale, they are just waiting for the political will. Various models, such as the European Climate Foundation’s Roadmap 2050, show that implementing these existing technologies would bring about an 85 per cent drop in carbon emissions by 2050. The idea that we need silver-bullet technologies to be developed before the green technology revolution can happen is a myth. The revolution is waiting to begin.

Climate call

The barriers preventing the creation of a low-carbon society are not technological but political and financial. That’s why at a landmark London conference convened by the UK’s Institution of Mechanical Engineers, 11 national engineering institutions representing 1.2 million engineers from across the globe, under the banner of the Future Climate project, made a joint call for action at December’s COP17 climate change conference in Durban, South Africa.

The statement calls on governments to move from warm words to solid actions. They need to introduce legislation and financial support to get these technologies out of the workshop and into our homes and businesses and onto our roads. Targeted regulation and taxation will also drive innovation. This will require bold politics, and spending at a time when money is scarce. It is far from unaffordable, however. The UK’s Committee on Climate Change, which advises the British government, continues to support the view of the Stern reportMovie Camera – an assessment of the climate change challenge in the UK – that the move to a low-carbon society will cost no more than 1 per cent of GDP by 2050.

Resistance to wind turbines and the power lines they feed, nuclear power and electric cars, as well as the economic costs, all make public opinion a powerful brake on change. However the alternative seems certain to be worse. It is not only the challenges of a deteriorating climate: with inaction comes a great risk to our economy in the long term. The green technology revolution, just like the industrial revolution before it, will give jobs to those countries which have created the right conditions for it to flourish.

China in front

Which countries these will be is still an open question. India, Germany, Australia and the UK were among the nations signed up to the Future Climate statement, whereas the world’s largest greenhouse gas emitters – China and the US – were not. When it comes to investment in clean technology, however, that’s not the whole story.

Although China is continuing to build coal-fired electricity plants at an alarming rate to power its rapid economic growth, the UN Environment Programme confirmed last month that it is now by far the world’s biggest investor in renewable energy. Last year, China’s wind, solar and biomass power industries received $49 billion of new investment, a third of the global total, and it now has the largest installed wind capacity in the world. When predicting who the front runner in this next great technological revolution will be, it is difficult to see past the emerging superpower to the east.

The US is going in the opposite direction. A natural gas rush driven by the development of controversial “fracking” techniques over the past decade has echoes of the oil rush that transformed Texas a century ago. The Financial Times reports that just one company, BHP Billiton, is investing as much as $79 billion in US shale gas fields – over three times the amount invested in all US renewables in a year. This will secure cheap energy in the short term, but it is a finite resource and ultimately a dead end. In due course we could face the interesting prospect of the US turning to China to acquire its wind turbine technology.

Nuclear elephant

Investment in renewable energy is vital for a prosperous, low-carbon society. However, decision-makers cannot ignore the elephant in the room – nuclear power. The enormous cost of implementing 100 per cent renewable power is not realistic for most nations, so nuclear offers our best chance of making a low-carbon society achievable and affordable. Yet the incident at Fukushima earlier this year has reinforced some long-standing concerns.

Unlike road use or smoking, nuclear power stirs anxieties in many of us that are out of proportion with its true risks. This is not to be complacent about the potential danger of a nuclear plant, but it is striking that nuclear power has killed fewer than 5000 people in its entire history. Compare that with coal mining, which in just one year and in one country – China in 2006 – killed 4700.

Germany’s decision to phase out all nuclear power as a result of Fukushima will most likely have unintended consequences. The Association of German Engineers has estimated that it will cost €53 billion every year in Germany to close down its nuclear generation and switch to 100 per cent renewable energy. It will be interesting to see how public opinion, now so clearly against nuclear power, responds as the economic costs become apparent.

Any technological revolution requires two crucial ingredients – engineers to design, develop and manufacture the technology, and politicians to help create the legislative, behavioural and societal environment that allows change to happen. Today’s engineers have fulfilled their side of the bargain. It is time for our politicians to show their mettle.

Colin Brown is director of engineering at the UK’s Institution of Mechanical Engineers

Climate change set to increase ozone-related deaths over next 60 years, scientists warn

Climate change set to increase ozone-related deaths over next 60 years, scientists warn.

ScienceDaily (Sep. 27, 2011) — Scientists are warning that death rates linked to climate change will increase in several European countries over the next 60 yrs.

A new study, which is being presented at the European Respiratory Society’s Annual Congress in Amsterdam, predicts that Belgium, France, Spain and Portugal will see the biggest climate-induced increase in ozone-related deaths over the next 60 years.

The research is part of the Climate-TRAP project and its health impact assessment lead by Prof Bertil Forsberg from the Umea University in Sweden. The aim is to prepare the health sector for changing public health needs due to climate change.

According to the World Health Organization (WHO), climate change that has occurred since the 1970s caused over 140,000 excess deaths annually by the year 2004. In addition to its impact on clean air, drinking water and crop production, many deadly diseases such as malaria and those which cause diarrhea are particularly sensitive to climate change.

In this new research, the scientists used emission scenarios and models to assess the health impacts of a changing climate. They took projections from two greenhouse gas emission scenarios, A2 and A1B, and two global climate models, ECHAM4 and HADLEY, to simulate how the various future ozone levels are affected by climate change.

They compared four periods: baseline period (1961-1990); the current situation (1990-2009); nearer future (2012-2050); and further future (2041-2060).

The findings revealed that since 1961, Belgium, Ireland, The Netherlands and the UK have seen the biggest impact on ozone-related deaths due to climate change. The results predicted that the biggest increase over the next 50 yrs is likely to be seen in Belgium, France, Spain and Portugal, who could expect an increase of between 10 and 14%. However, Nordic and Baltic countries are predicted to see a decrease over the same period.

Dr Hans Orru, air pollution expert from the Umea University and University of Tartu in Estonia, explains: “Ozone is a highly oxidative pollutant, linked with hospitalisations and deaths due to problems with the respiratory system. Ground-level ozone formation is due to rise as temperatures increase with climate change. The results of our study have shown the potential effects that climate change can have on ozone levels and how this change will impact upon the health of Europeans.”

Professor Marc Decramer, President of the ERS, said: “Outdoor air pollution is the biggest environmental threat in Europe. If we do not act to reduce levels of ozone and other pollutants, we will see increased hospital admissions, extra medication and millions of lost working days. As part of the European Respiratory Roadmap, which was launched last month, the ERS is calling for a collaborative approach between health professionals and policy makers, to protect vulnerable populations from the damaging effects air pollutants can have.”

Story Source:

The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by European Lung Foundation, via EurekAlert!, a service of AAAS.


 

Huge Floods in Manila as Typhoon Hits Philippines

Huge Floods in Manila as Typhoon Hits Philippines – TIME.

(MANILA, Philippines) — Massive flooding hit the Philippine capital on Tuesday as typhoon winds and rains isolated the historic old city where residents waded in waist-deep waters, dodging tree branches and debris. At least seven people were killed.

Authorities ordered more than 100,000 people across the country to shelter from Typhoon Nesat’s rains and wind gusts of up to 106 miles (170 kilometers) per hour. Schools and offices were shuttered, and thousands were stranded by grounded flights and ferries kept in ports.(See photos of Typhoon Roke hitting Japan earlier this year.)

The typhoon made landfall before dawn over eastern mountainous provinces of Isabela and Aurora, which face the Pacific Ocean, then headed inland through farmlands north of Manila, the government weather bureau said. It was packing sustained winds of 87 mph (140 kph).

The first reported death was a 1 year old who drowned in the central island province of Cataduanes after falling into a river, the government disaster agency reported. As the typhoon moved into Manila, a mother and child were killed after their house was hit by a falling tree in the suburb of Caloocan, and four were reported killed by a collapsing wall in the suburb of Valenzuela.

Four fishermen were missing while more than 50 others were rescued along eastern shores after their boats overturned in choppy seas. Forecasters warned of 12-foot-high (4-meter-high) waves.

Along downtown Manila’s baywalk, cars and buses were stuck and residents waded through floodwaters as waves as high as palm trees washed over the seawall, turning a six-lane highway into a huge brown river.(See more on how hurricanes are named.)

Sidewalks and entrances to buildings were swamped and vehicles struggled to navigate the narrow streets.

Manila Hospital moved patients from its ground floor, where waters were neck-deep, spokeswoman Evangeline Morales said. Hospital generators were flooded and the building had no power since early Tuesday.

Visibility in the city was poor, with pounding rains obscuring the view. Emergency workers were evacuating river areas in the city that are notorious for flooding.

An Associated Press photographer said soldiers and police in trucks were moving thousands of residents, mostly women and children, from the Baseco shanty facing Manila port after many houses were washed away. Male family members were reluctant to leave saying they wanted to guard their property.

Residents in one neighborhood of Quezon City, a Manila suburb, were fleeing their homes due to rising water from the nearby San Mateo River, radio reported.

In the financial district of Makati, a billboard fell on two cars and a bus, causing injuries.

With its immense 400-mile (650-kilometer) cloud band, the typhoon threatened to foul weather across the entire main island of Luzon as it moves across the Philippines toward the South China Sea late Wednesday or early Thursday toward southern China.

Heavy downpours and winds prompted the closure of government offices, schools and universities in the capital, while scores of domestic flights were canceled and inter-island ferries grounded, stranding thousands. The Philippine Stock Exchange and U.S. Embassy were also closed Tuesday. Waters at the gates of the embassy compound, which is located along Manila Bay, reached chest-deep.

A tornado in Isabela’s Maconancon town ripped off the roofs of at least five houses, injuring two people, police said.

Power was cut in many parts of Luzon, including in Manila, where hospitals, hotels and emergency services used generators. Tree branches and torn tarpaulins littered the flooded streets. Traffic was light as most people stayed indoors.

About 112,000 people were ordered to leave their homes in five towns prone to flash floods and landslides in central Albay province. By Monday, more than 50,000 had moved to government-run evacuation centers and relatives’ homes, officials said.

“We can’t manage typhoons, but we can manage their effects,” Albay Gov. Joey Salceda said.

Authorities were monitoring farming communities at the base of Mayon volcano in Albay, about 212 miles (340 kilometers) southeast of Manila.

Tons of ash have been deposited on Mayon’s slopes by past eruptions, and mudslides caused by a typhoon in 2006 buried entire villages, leaving about 1,600 people dead and missing.

The typhoon bore down on the Philippines exactly two years after nearly 500 people died in the worst flooding in decades in Manila, a city of 12 million, when a tropical storm hit.

Residents commemorated the anniversary by offering prayers and planting trees Monday.

Nesat is the 16th cyclone to lash the Philippines this year. The geography of the archipelago makes it a welcome mat for about 20 storms and typhoons forming in the Pacific each year.

Associated Press writer Oliver Teves, photographer Bullit Marquez and videographer Joeal Calupitan contributed to this report.

Construction drives China's 'carbonizing dragon'

A ‘carbonizing dragon’: Construction drives China’s growing CO2 emissions.

ScienceDaily (Oct. 4, 2011) — Constructing buildings, power-plants and roads has driven a substantial increase in China’s carbon dioxide emission growth, according to a new study involving the University of East Anglia (UEA).

Fast growing capital investments in infrastructure projects led to the expansion of the construction industry and its energy and CO2 intensive supply chain, such as steel and cement production. As a result of this transformation of China’s economy, more and more CO2 was released per unit of gross domestic product — a reversion of a long-term trend.

Recently China became the world’s largest consumer of energy and emitter of CO2, overtaking the US. Previously the country’s greenhouse gas emissions growth was driven by rising consumption and exports. Today this growth is offset by emission savings from efficiency increases, but these savings are being hindered by the building of infrastructure — which is important as it dictates tomorrow’s emissions, the international team of researchers concludes.

The study, entitled “A ‘Carbonizing Dragon’: China’s fast growing CO2 emissions revisited”, is published in the journal Environmental Science & Technology. It emphasizes that putting a low carbon infrastructure in place in China as well as other emerging and developing economies from the beginning is a key global challenge to avoid ‘carbon lock-in’ — where a country could be stuck on a path of high emissions — which would have a significant and persistent impact on future emissions.

“The carbon intensive nature of capital investment in heavy industry, large infrastructure building projects, and energy production, might be hard to avoid as China tries to instigate a virtuous cycle of high rates of investment and economic growth,” explained Giovanni Baiocchi, from Norwich Business School at UEA and the lead UK author of the study.

“The high levels of CO2 emissions from capital investment might only be temporary as, with economic development, investment moves into more high-tech and greener technologies,” added Dr Baiocchi, a senior lecturer in business and climate change. “However, it is crucial that China now invests in the right kind of infrastructure to limit the growth of CO2 emissions that causes global warming. The type of infrastructure put in place today will also largely determine future mitigation costs.”

The study’s lead author Jan Minx, from the Potsdam Institute for Climate Impact Research (PIK) and the Technical University of Berlin, said: “Up to 2002 there has been a race between consumption growth and efficiency gains. However, the recent rise in emissions is completely due to the massive structural change of China’s economy. Emissions grow faster and faster, because CO2 intensive sectors linked to the building of infrastructure have become more and more dominant. China has developed into a ‘carbonizing dragon’.”

The researchers conducted a ‘structural decomposition’ analysis of input-output data for 1992 to 2007 — the most recent official data available — which allowed them to assign changes in emission over time to a set of drivers such as consumption growth, efficiency gains or structural change.

They found that emissions almost tripled between 1992 and 2007, growing by about four billion tonnes, with 70% of this growth happening between 2002 and 2007. The average annual CO2 emission growth alone in this period was similar in size to the total CO2 emissions in the UK. While exports showed the fastest CO2 emission growth at one point, capital investments and the construction industry then overtook.

According to the study another important driver of emissions is urbanization — emissions from household consumption are more significant than the sheer growth of population or even the decreasing household size. When people move from the countryside to the city lifestyle changes take place. Urban dwellers, for example, tend to seek gas heating and electricity and also depend more upon a transport infrastructure to get to work, all of which implies a higher per capita carbon footprint.

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Arctic ozone loss at record level

BBC News – Arctic ozone loss at record level.

 

The Arctic ozone hole lay over over populated regions for parts of winter and spring

Ozone loss over the Arctic this year was so severe that for the first time it could be called an “ozone hole” like the Antarctic one, scientists report.

About 20km (13 miles) above the ground, 80% of the ozone was lost, they say.

The cause was an unusually long spell of cold weather at altitude. In cold conditions, the chlorine chemicals that destroy ozone are at their most active.

It is currently impossible to predict if such losses will occur again, the team writes in the journal Nature.

Early data on the scale of Arctic ozone destruction were released in April, but the Nature paper is the first that has fully analysed the data.

“Winter in the Arctic stratosphere is highly variable – some are warm, some are cold,” said Michelle Santee from Nasa’s Jet Propulsion Laboratory (JPL).

“But over the last few decades, the winters that are cold have been getting colder.

Start Quote

Why [all this] occurred will take years of detailed study”

Michelle Santee JPL

“So given that trend and the high variability, we’d anticipate that we’ll have other cold ones, and if that happens while chlorine levels are high, we’d anticipate that we’d have severe ozone loss.”

Ozone-destroying chemicals originate in substances such as chlorofluorocarbons (CFCs) that came into use late last century in appliances including refrigerators and fire extinguishers.

Their destructive effects were first documented in the Antarctic, which now sees severe ozone depletion in each of its winters.

Their use was progressively restricted and then eliminated by the 1987 Montreal Protocol and its successors.

The ozone layer blocks ultraviolet-B rays from the Sun, which can cause skin cancer and other medical conditions.

Longer, not colder

Winter temperatures in the Arctic stratosphere do not generally fall as low as at the southern end of the world.

Polar stratospheric clouds Ozone destruction takes place within polar stratospheric clouds, with chlorine the main culprit

No records for low temperature were set this year, but the air remained at its coldest for an unusually long period of time, and covered an unusually large area.

In addition, the polar vortex was stronger than usual. Here, winds circulate around the edge of the Arctic region, somewhat isolating it from the main world weather systems.

“Why [all this] occurred will take years of detailed study,” said Dr Santee.

“It was continuously cold from December through April, and that has never happened before in the Arctic in the instrumental record.”

The size and position of the ozone hole changed over time, as the vortex moved northwards or southwards over different regions.

Some monitoring stations in northern Europe and Russia recorded enhanced levels of ultraviolet-B penetration, though it is not clear that this posed any risk to human health.

While the Arctic was setting records, the Antarctic ozone hole is relatively stable from year to year.

This year has seen ozone-depleting conditions extending a little later into the southern hemisphere spring than usual – again, as a result of unusual weather conditions.

Chlorine compounds persist for decades in the upper atmosphere, meaning that it will probably be mid-century before the ozone layer is restored to its pre-industrial health.

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Mid-Latitude Cyclone over the United States

Mid-Latitude Cyclone over the United States : Natural Hazards.

Mid-Latitude Cyclone over the United States

acquired September 26, 2011 download large image (17 MB, JPEG)
acquired September 25 – 27, 2011 download web resolution GOES animation (7 MB, QuickTime)
acquired September 25 – 27, 2011 download high definition GOES animation (74 MB, QuickTime)

At 3:05 p.m. Eastern Daylight Time on September 26, 2011, the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite observed a mid-latitude cyclone over the midwestern United States. The center of the storm appeared immediately west of Lake Michigan.

The Capital Weather Gang at The Washington Post reported that the storm was at its most mature stage on September 26. Sporting a comma shape spanning hundreds of kilometers, the storm was comprised of a combination of warm, moist air (clouds) and cold, dry air (cloud-free areas).

Mid-latitude cyclones drive most of the stormy weather in the continental United States. Development of these cyclones often involves a warm front from the south meeting a cold front from the north. In the Northern Hemisphere, cyclones move in a counterclockwise direction. (In the Southern Hemisphere, cyclones are clockwise.) The bands of cold and warm air wrap around a center of low pressure, and air rising near the center spurs the development clouds and precipitation.

Justin Berk, a meteorologist based in Baltimore, explains that in this region, “cold air eventually wins out and wraps completely around a storm. This is called a ‘cold core’ storm and has cut itself off from the main flow of the jet stream.” This, says Berk, is why the September 26 storm appears stalled near Chicago.

An animation of the storm from the Geostationary Operational Environmental Satellites (GOES) shows the storm’s progress from September 25 to September 27.

  1. References

  2. Samenow, J. (2011, September 27). An immaculate mid-latitude cyclone and its decay. Capital Weather Gang. The Washington Post. Accessed September 27, 2011.
  3. University of Illinois at Urbana-Champaign. Midlatitude Cyclones. Accessed September 27, 2011.

NASA image courtesy Jeff Schmaltz, the MODIS Rapid Response Team at NASA GSFC. Animation from the NASA/NOAA GOES Project Science Team. Caption by Michon Scott.

Instrument: 
Aqua – MODIS

Typhoon Roke

Typhoon Roke : Natural Hazards.

Typhoon Roke

acquired September 20, 2011 download large image (6 MB, JPEG)
acquired September 20, 2011 download GeoTIFF file (60 MB, TIFF)
acquired September 20, 2011 download Google Earth file (KMZ)

Typhoon Roke promises to bring unwelcome rain to areas of Japan still recovering from Typhoon Talas, which triggered landslides and floods across the Kii Peninsula in early September 2011. The new typhoon has the potential to trigger additional landslides and floods, particularly as rainwater builds up behind mud dams formed by landslides during Typhoon Talas. Fearing floods from two rivers, officials in the city of Nagoya ordered the evacuation of 80,000 people and advised more than a million more to evacuate, said The Japan Times.

Typhoon Roke was on its way to becoming a very strong storm when the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite acquired this image at 1:45 p.m. local time (4:45 UTC) on September 20, 2011. The storm is large and well-formed, with a distinct eye. An hour after the image was taken, Roke had winds of 176 kilometers (109 miles) per hour per hour (95 knots), making it a Category 2 storm. Seven hours later, the storm intensified to Category 4, with winds reaching 213 kilometers (132 miles) per hour ( 115 knots).

Roke was moving northeast toward the Japanese island of Honshu at 35 kilometers per hour (22 miles/hour) and was forecast to come ashore on September 21, according to the Japan Meteorological Agency. Roke could bring as much as 500 millimeters (20 inches) of rain to parts of Japan.

  1. References

  2. Japan Meteorological Agency. (2011, September 20). Tropical cyclone information. Accessed September 20, 2011.
  3. The Japan Times. (2011, September 20). Nagoya orders 80,000 out as typhoon nears. Accessed September 20, 2011.
  4. Unisys Weather. (2011, September 20). Typhoon Roke. Data from Joint Typhoon Warning Center. Accessed September 20, 2011.

NASA image courtesy Jeff Schmaltz, MODIS Rapid Response Team at NASA GSFC. Caption by Holli Riebeek.

Instrument: 
Aqua – MODIS

Hurricane Irene from space

Short Sharp Science: Irene from space: covers Atlantic coastline.

Caitlin Stier, contributor
irene.jpg
(Image: NASA)

Hurricane Irene is expected to strike North Carolina Saturday before heading up the coast – potentially hitting the New York metropolitan area and impacting a swath of 55 million people.

The category 2 storm has sustained winds topping off at 165 kilometres per hour. Storm trackers were worried Irene would strike as a category 3 hurricane, but the storm weakened overnight. The National Hurricane Center is not currently forecasting an increase in intensity before it makes landfall.

Several states have declared states of emergency and evacuations have been ordered for residents as far north as New Jersey. Previous rainfall combined with a new moon tide on Sunday could heighten the slow-moving storm’s impact.

Strong hurricane strikes in the northeast are rare but the impending storm raises questions about the readiness of New York City considering the torrential rains and storm surge possible with intense hurricanes. The city is preparing for a potential shutdown of the subway system if sustained winds reach 63 kilometres per hour.

This image from the International Space Station shows the giant storm over the Caribbean on Monday. NASA satellites show the diameter of the storm is about one-third of the entire Atlantic coastline.

Fleet of hybrid airships to conquer Arctic

One Per Cent: Fleet of hybrid airships to conquer Arctic.

Joel Shurkin, contributor

HAV2.jpg

(Image: HAV)

Travelling through the Arctic is notoriously difficult and climate change is making it even harder. But there is a way to rise above the problem: the latest generation of lighter-than-air vehicles. Canadian company Discovery Air has signed a contract with the UK’s Hybrid Air Vehicles (HAV) to buy around 45 new hybrid air vehicles. These aircraft will be used across Canada’s Northwest Territories.

Whether taking out lumber from the forests or helping people access remote villages, transportation in Arctic Canada can be extrememly daunting. Most transportation is either by air, which is expensive, by boat, or by ice road. Rising winter temperatures, due to climate change, are likely to make Canada’s ice roads less stable and reduce the amount of time in winter in which they can safely be used.

Gordon Taylor, marketing director for HAV, says the vessels are technically neither airships nor blimps. While they do make use of non-explosive helium for lift, they also get substantial lift from the aerodynamic design of the fuselage.

HAV already has a major contract for hybrid vehicles with the US Defence Department for long-endurance surveillance vessels.

The vessels Discovery Air has ordered are HAV’s model 366, which Taylor says can carry 50 tonnes if they take off horizontally like an airplane and around 30 tonnes if they take off vertically. Not even the largest helicopters in the world can match that, explains Taylor.

One hundred and ten metres long, the vessels can reach altitudes of almost 3000 metres and can take off and land almost anywhere. The cargo will fit in the fuselage for very long trips or can hang beneath the ship for shorter ones. Later models can also be flown remotely.

Mysteries of ozone depletion continue 25 years after the discovery of the Antarctic ozone hole

Mysteries of ozone depletion continue 25 years after the discovery of the Antarctic ozone hole.

ScienceDaily (Aug. 29, 2011) — Even after many decades of studying ozone and its loss from our atmosphere miles above Earth, plenty of mysteries and surprises remain, including an unexpected loss of ozone over the Arctic this past winter, an authority on the topic said in Denver Colorado on May 29. She also discussed chemistry and climate change, including some proposed ideas to “geoengineer” Earth’s climate to slow down or reverse global warming.

The talk happened at the 242nd National Meeting & Exposition of the American Chemical Society (ACS), being held this week.

In a Kavli Foundation Innovations in Chemistry Lecture, Susan Solomon, Ph.D., of the University of Colorado, Boulder, said that the combined efforts of scientists, the public, industry and policy makers to stop ozone depletion is one of science’s greatest success stories, but unanswered questions remain. And ozone is still disappearing.

“We’re no longer producing the primary chemicals — chlorofluorocarbons (CFCs) — that caused the problem, but CFCs have very long lifetimes in our atmosphere, and so we’ll have ozone depletion for several more decades,” said Solomon. “There are still some remarkable mysteries regarding exactly how these chlorine compounds behave in Antarctica — and it’s amazing that we still have much to learn, even after studying ozone for so long.”

The ozone layer is crucial to life on Earth, forming a protective shield high in the atmosphere that blocks potentially harmful ultraviolet rays in sunlight. Scientists have known since 1930 that ozone forms and decomposes through chemical processes. The first hints that human activity threatened the ozone layer emerged in the 1970s, and included one warning from Paul Crutzen, Ph.D., that agricultural fertilizers might reduce ozone levels. Another hint was from F. Sherwood Rowland, Ph.D., and Mario Molina, Ph.D., who described how CFCs in aerosol spray cans and other products could destroy the ozone layer. The three shared a 1995 Nobel Prize in Chemistry for that research. In 1985, British scientists discovered a “hole,” a completely unexpected area of intense ozone depletion over Antarctica. Solomon’s 1986 expedition to Antarctica provided some of the clinching evidence that underpinned a global ban on CFCs and certain other ozone-depleting gases.

Evidence suggests that the ozone depletion has stopped getting worse. “Ozone can be thought of as a patient in remission, but it’s too early to declare recovery,” said Solomon. And surprises, such as last winter’s loss of 40% of the ozone over the Arctic still occur due to the extremely long lifetimes of ozone-destroying substances released years ago before the ban.

Solomon also took listeners on a tour of gases and aerosols that affect climate change and described how these substances can contribute to global warming.

“On the thousand-year timescale, carbon dioxide is by far the most important greenhouse gas produced by humans, but there are some other interesting — though much less abundant — gases such as perfluorinated compounds that also last thousands of years and similarly affect our climate for millennia,” said Solomon.

Increases in atmospheric “greenhouse gases” such as carbon dioxide trap heat in the atmosphere, causing Earth’s temperature to creep upward. Global warming is causing ocean levels to rise and could lead some regions to become dry “dust bowls.”

Dealing with global warming has prompted a lot of interesting research on how to reduce greenhouse gas emissions, how to adapt to a changing climate and on the possibility of ‘geoengineering’ to cool the climate.

“Recent studies on ‘geoengineering’ the Earth’s climate involve stratospheric particles of different sorts,” she said. “Most of these schemes involve sulfate particles, but other types have been proposed.”

The talk took place on Monday, August 29 in the Wells Fargo Theater at the Colorado Convention Center.

Sponsored by The Kavli Foundation, a philanthropic organization that supports basic scientific research, the lectures are designed to address the urgent need for vigorous, “outside the box” thinking by scientists as they tackle the world’s mounting challenges, including climate change, emerging diseases, and water and energy shortages.

“We are dedicated to advancing science for the benefit of humanity, promoting public understanding of scientific research, and supporting scientists and their work,” said Kavli Foundation President Robert W. Conn in a statement. “The Kavli Foundation Innovations in Chemistry Lecture program at the ACS national meetings fits perfectly with our commitment to support groundbreaking discovery and promote public understanding.”

The Kavli lectures debuted at the Anaheim meeting in March during this International Year of Chemistry and will continue through 2013. They will address the urgent need for vigorous, new, “outside-the-box”- thinking, as scientists tackle many of the world’s mounting challenges like climate change, emerging diseases, and water and energy shortages. The Kavli Foundation, an internationally recognized philanthropic organization known for its support of basic scientific innovation, agreed to sponsor the lectures in conjunction with ACS in 2010.