Beijing is not the only Asian city with lethal air pollution

John Vidal in the Guardian (UK): Air pollution in Beijing has been described as "apocalyptic" this week with people choking their way through murky streets, short of breath and their eyes stinging from toxic air. But Beijing is just one of hundreds of cities, largely in Asia, where poisonous air is now the fastest growing cause of death in urban populations.

In the past few months there have been acute air pollution incidents reported in Bangladesh, Iran, Afghanistan, Nepal, and Pakistan. In Tehran, the desperate authorities had to close all public offices, schools, universities and banks twice in the last two months; In Nepal the army has had to give up its cars and in Kabul it has been reported that there are now more deaths as a result of air and water pollution than from conflict.

Statistics are unreliable, with few cities able to monitor accurately either the source or the level of the cocktail of pollutants emitted by traffic, ships, industry, brick kilns and domestic heating. But go to the hospitals and doctors will tell you that up to 80% of people admitted come with respiratory or other chronic diseases linked to air pollution. In Tehran, more than 4,500 people were said to have died last year because of air pollution – but because cancers can take years to develop the true figure may be far higher.

Perhaps because there are no drugs available to counter air pollution, it has never been taken as seriously by governments as other diseases like HIV/Aids or malaria, even though the World Health Organisation estimates more than 2 million people worldwide die every year from bad air and that it is now among the top 10 killers in the world. But governments may have to act as new research shows it to be rapidly worsening....

Smog over Shanghai, shot by Seader, Wikimedia Commons, under the Creative Commons CC0 1.0 Universal Public Domain Dedication

China pollution anger spills into state media

Terra Daily via AFP: Public anger in China at dangerous levels of air pollution, which blanketed Beijing in acrid smog, spread Monday as state media queried official transparency and the nation's breakneck development. The media joined Internet users in calling for a re-evaluation of China's modernisation process, which has seen rapid urbanisation and dramatic economic development at the expense of the environment.

Dense smog shrouded large swathes of northern China at the weekend, cutting visibility to 100 metres (yards) in some areas and forcing flight cancellations. Reports said dozens of building sites and a car factory in the capital halted work as an anti-pollution measure.

Doctors at two of the city's major hospitals said the number of patients with respiratory problems had increased sharply in the past few days, state media reported.

"Now it has been dark with pollution for three days, at least people are starting to realise how important the environment is," said one posting on China's Twitter-like Sina Weibo.

At the height of the smog Beijing authorities said readings for PM2.5 -- particles small enough deeply to penetrate the lungs -- hit 993 micrograms per cubic metre, almost 40 times the World Health Organisation's safe limit....

Smog in Beijing in 2006, shot by Berserkerus, Wikimedia Commons, under the Creative Commons Attribution-Share Alike 3.0 Unported license

NASA chases climate change clues into the stratosphere

Science Daily: Starting this month, NASA will send a remotely piloted research aircraft as high as 65,000 feet over the tropical Pacific Ocean to probe unexplored regions of the upper atmosphere for answers to how a warming climate is changing Earth.

The first flights of the Airborne Tropical Tropopause Experiment (ATTREX), a multi-year airborne science campaign with a heavily instrumented Global Hawk aircraft, will take off from and be operated by NASA's Dryden Flight Research Center at Edwards Air Force Base in California. The Global Hawk is able to make 30-hour flights.

Water vapor and ozone in the stratosphere can have a large impact on Earth's climate. The processes that drive the rise and fall of these compounds, especially water vapor, are not well understood. This limits scientists' ability to predict how these changes will influence global climate in the future. ATTREX will study moisture and chemical composition in the upper regions of the troposphere, the lowest layer of Earth's atmosphere. The tropopause layer between the troposphere and stratosphere, 8 miles to 11 miles above Earth's surface, is the point where water vapor, ozone and other gases enter the stratosphere.

Studies have shown even small changes in stratospheric humidity may have significant climate impacts. Predictions of stratospheric humidity changes are uncertain because of gaps in the understanding of the physical processes occurring in the tropical tropopause layer. ATTREX will use the Global Hawk to carry instruments to sample this layer near the equator off the coast of Central America.

"The ATTREX payload will provide unprecedented measurements of the tropical tropopause," said Eric Jensen, ATTREX principal investigator at NASA's Ames Research Center in Moffett Field, Calif. "This is our first opportunity to sample the tropopause region during winter in the northern hemisphere when it is coldest and extremely dry air enters the stratosphere."...

NASA In its new white-and-blue NASA livery, an early development model of the Global Hawk unmanned aircraft rests on the ramp at the Dryden Flight Research Center, Edwards AFB, Calif. Photo Credit: NASA

New study documents the natural relationship between CO2 concentrations and sea level

AlphaGalileo via the National Oceanography Centre: By comparing reconstructions of atmospheric CO2 concentrations and sea level over the past 40 million years, researchers based at the National Oceanography Centre, Southampton have found that greenhouse gas concentrations similar to the present (almost 400 parts per million) were systematically associated with sea levels at least nine metres above current levels.

The study determined the ‘natural equilibrium’ sea level for CO2 concentrations ranging between ice-age values of 180 parts per million and ice-free values of more than 1,000 parts per million. It takes many centuries for such an equilibrium to be reached, therefore whilst the study does not predict any sea level value for the coming century, it does illustrate what sea level might be expected if climate were stabilized at a certain CO2 level for several centuries.

Lead author Dr Gavin Foster, from Ocean and Earth Science at the University of Southampton which is based at the centre, said, “A specific case of interest is one in which CO2 levels are kept at 400 to 450 parts per million, because that is the requirement for the often mentioned target of a maximum of two degrees global warming.”

The researchers compiled more than two thousand pairs of CO2 and sea level data points, spanning critical periods within the last 40 million years. Some of these had climates warmer than present, some similar, and some colder. They also included periods during which global temperatures were increasing, as well as periods during which temperatures were decreasing.

...The researchers found that the natural relationship displays a strong rise in sea level for CO2 increase from 180 to 400 parts per million, peaking at CO2 levels close to present-day values, with sea level at 24 +7/-15 metres above the present, at 68 per cent confidence limits.

“This strong relationship reflects the climatic sensitivity of the great ice sheets of the ice ages,” said Dr Foster. “It continues above the present level because of the apparently similar sensitivity of the Greenland and West Antarctic ice sheets, plus possibly some coastal parts of East Antarctica.”...

The Mertz Glacier in Antarctica, shot by Jacques.verron, Wikimedia Commons, under the Creative Commons Attribution-Share Alike 3.0 Unported license

Tropical trees are largest emitter of methane in their ecosystem

The Open University News: Researchers at The Open University have found that trees in Bornean rainforests emit more methane than any other element of the ecosystem, which provides a new understanding about sources of this powerful greenhouse gas from tropical ecosystems.

In a paper titled Trees are major conduits for methane egress from tropical forested wetlands by Dr Vincent Gauci and Sunitha Pangala, published in New Phytologist on 18 December, the researchers announced new findings which show that trees in tropical peat forests of Southeast Asia release more methane through their stems than is emitted from the soil surface.

Sunitha Pangala, final year PhD student at The Open University’s Centre for Earth, Planetary Space and Astronomical Research, and lead author on the paper said: "This is the first study to measure methane release from tree stems in tropical peat swamps and evaluate its importance at an ecosystem level. Our research establishes that trees in tropical peat swamps are the largest emission pathway of methane in that ecosystem."

Previously it was thought that methane was only emitted via diffusion and bubbles at the wetland surface. The team measured methane emissions from healthy tree stems in a tropical forested peatland in the upper Sebangau River catchment in Borneo. They found significant quantities of methane being released from the stems of seven of the eight tree species studied. They estimated up to 87% of the methane are released from tree stems, highlighting that the previous methane emission inventories of this ecosystem may have been severely underestimated.

"This work challenges our previous understanding of how these ecosystems exchange methane with the atmosphere and adds another piece to the tropical methane emission puzzle,” said Dr Vincent Gauci, Senior Lecturer, Earth Systems, and the project’s leader. "It further shows that for wet tropical forested ecosystems, the like of which span south America, Africa and southeast Asia, researchers may have been missing most of the methane emitted from these ecosystems if they neglected to measure tree stem emissions.”...

A 1859 rendering of Borneo

Declining air pollution levels continue to improve life expectancy in US

A press release from the Harvard School of Public Health: A new study led by researchers at Harvard School of Public Health (HSPH) has found an association between reductions in fine particulate matter and improved life expectancy in 545 counties in the U.S. from 2000 to 2007. It is the largest study to date to find beneficial effects to public health of continuing to reduce air pollution levels in the U.S.  The study appears in the December 3, 2012 online edition of the journal Epidemiology.

“Despite the fact that the U.S. population as a whole is exposed to much lower levels of air pollution than 30 years ago—because of great strides made to reduce people’s exposure—it appears that further reductions in air pollution levels would continue to benefit public health,” said lead author Andrew Correia, a PhD candidate in the Department of Biostatistics at HSPH.

The study looked at the effects on health of fine particulate matter, small particles of 2.5 micrometers or less in diameter—referred to as PM2.5. Numerous studies have shown associations between acute and chronic exposure to fine particle air pollution and cardiopulmonary disease and mortality. Studies have also shown that reductions in air pollution are associated with reductions in adverse health effects and improved life expectancy. Air pollution has been declining steadily in the U.S. since 1980, but the rate has slowed in the years since 2000. The HSPH researchers wanted to know whether the relatively smaller decreases in PM2.5 levels since 2000 are still improving life expectancy.

Controlling for socioeconomic status, smoking prevalence, and demographic characteristics, the results showed that a decrease of 10 micrograms per cubic meter (10 μg/m3 ) in the concentration of  PM2.5 during the period 2000 to 2007 was associated with an average increase in life expectancy of 0.35 years in 545 U.S. counties.

The research expanded on a 2009 study published in the New England Journal of Medicine by some of the same authors (Pope, Ezzati, and Dockery) that found that reduced air pollution was associated with increased life expectancy in 211 urban counties. This new study looked at more recent data, more than two-and-a-half times as many counties, and included both rural and urban areas. The findings showed that there’s a stronger association between declining air pollution and increased life expectancy in more urban, densely populated areas than in rural areas. The results also suggested that reduced levels of air pollution may be more beneficial to women than to men….

A double air inversion over Los Angeles, from the EPA

Canopy structure more important to climate than leaf nitrogen levels

Terra Daily via SPX: Claims that forest leaves rich in nitrogen may aid in reflecting infrared radiation - helping cool the atmosphere - have been challenged by new research that shows that the structure of tree canopies is a more important factor in infrared reflection. Recent studies have noticed a strong positive correlation between the concentration of nitrogen in forests and infrared reflectance measured from aircraft and satellites.

Some scientists have suggested this demonstrates a previously overlooked role for nitrogen in regulating the earth's climate system.

However, a new paper in Proceedings of the National Academy of Sciences, shows that the apparent relationship between leaves' nitrogen levels and infrared reflection is spurious and it is in fact the structure of forest canopies (the spatial arrangement of the leaves) that determines their ability to reflect infrared light.

The authors, including Professor Philip Lewis and Dr Mathias Disney (UCL Geography), show that the richer in nitrogen individual leaves are the worse at reflecting infrared radiation they become.

However, the complex arrangements of trees with radically different arrangements of leaves within a forest can act to mask this effect, making it appear as if higher levels of leaf nitrogen are leading to increased infrared reflection....

A tree canopy in Sri Lanka's Sinharaja Forest Reserve, shot by Chamal N, Wikimedia Commons, under the Creative Commons Attribution-Share Alike 3.0 Unported license

Broecker talks future of climate change research

Shayna Owens in the Columbia Spectator: Thirty-seven years after Wallace Broecker, CC ’53, coined the terms “climate change” and “global warming” in his research, he still thinks that his predictions were “smack on.”

At a discussion on Tuesday sponsored by the Institute for Religion, Culture, and Public Life, Broecker and New York Times reporter John M. Broder, who covers energy and the environment, considered future solutions to global warming and how scientists can best implement them. Broder said that—especially in light of Hurricane Sandy, which ripped through New York City two weeks ago, causing mass flooding and power outages across the five boroughs—the topic of climate change needs to be addressed.

....“We’re spending incredibly large amounts of money on our military,” he said. “Why? That’s a small problem compared to CO2, but we’re spending nothing on CO2.”

Broder said that in Washington, there is an “issue of messaging,” noting that government officials may not be implementing the best strategies to stress the importance of addressing climate change. “Al Gore is probably the best example of this planetary emergency,” Broder said. “These are fear-based messages, and I don’t think they work very well.”

...Broecker, who called himself a “very optimistic person,” said he still harbors doubts about whether enough action will be taken. Somehow we have to get together and say, let’s not fight, let’s come up with some plan and get going,” he said....

Caspar David Friedrich's "Wanderer above the Sea of Fog," from 1818

Future warming likely to be on high side of climate projections, analysis finds

NCAR-UCAR Atmos News: Climate model projections showing a greater rise in global temperature are likely to prove more accurate than those showing a lesser rise, according to a new analysis by scientists at the National Center for Atmospheric Research (NCAR). The findings, published in this week’s issue of Science, could provide a breakthrough in the longstanding quest to narrow the range of global warming expected in coming decades and beyond.

NCAR scientists John Fasullo and Kevin Trenberth, who co-authored the study, reached their conclusions by analyzing how well sophisticated climate models reproduce observed relative humidity in the tropics and subtropics. The climate models that most accurately captured these complex moisture processes and associated clouds, which have a major influence on global climate, were also the ones that showed the greatest amounts of warming as society emits more greenhouse gas into the atmosphere.

“There is a striking relationship between how well climate models simulate relative humidity in key areas and how much warming they show in response to increasing carbon dioxide,” Fasullo says. “Given how fundamental these processes are to clouds and the overall global climate, our findings indicate that warming is likely to be on the high side of current projections.”

...The most common benchmark for comparing model projections is equilibrium climate sensitivity (ECS), or the amount of warming that eventually occurs in a model when carbon dioxide is doubled over preindustrial values. At current rates of global emission, that doubling will occur well before 2100.

For more than 30 years, ECS in the leading models has averaged around 5 degrees Fahrenheit (3 degrees Celsius).  This provides the best estimate of global temperature increase expected by the late 21st century compared to late 19th century values, assuming that society continues to emit significant amounts of carbon dioxide. However, the ECS within individual models is as low as 3 degrees F and as high as 8 degrees F, leaving a wide range of uncertainty that has proven difficult to narrow over the past three decades....

Computer models that more accurately depict dry conditions in a key part of the subtropical atmosphere are also more likely to predict greater climate warming from increased greenhouse gases. In this graphic, each star indicates one of 16 leading global climate models. The left axis ("warming") corresponds to equilibrium climate sensitivity (ECS) in degrees C, which is the amount of warming produced by each model when carbon dioxide concentrations in the atmosphere are doubled over preindustrial values. The bottom axis shows May-to-August relative humidity for a portion of the upper atmosphere between about 20,000 to 30,000 feet in height and between about 10° and 25° latitude south in the southern subtropics. (©UCAR. Image by Carlye Calvin, based on Fasullo and Trenberth, Science, 2012.)