[LINK] A link between air travel and deaths on the ground

[Tom Koltai]

http://web.mit.edu/newsoffice/2010/airplane-emissions-0928.html

Study suggests pollution from airplanes flying at ‘cruise’ altitudes
contributes to 8,000 deaths per year globally.
The atmosphere is full of natural and man-made chemicals, including
emissions from fuel combustion and byproducts of living organisms. Many
of these chemicals combine in the atmosphere to form tiny solid and
liquid particles known as “fine particulate matter” that are 2.5
micrometers or smaller (the average human hair is about 70 micrometers
in diameter, by comparison). While it’s not clear whether all of these
particles may be harmful, some are; the danger to humans comes when they
are inhaled and trapped in the lungs, where they can then enter the
bloodstream.

In 2004, the World Health Organization estimated that about one million
deaths per year are caused by air pollution, and several epidemiological
studies have linked air pollution to the development of cardiovascular
and respiratory illnesses, including lung cancer. Those studies tracked
thousands of adults over many years to measure their exposure to air
pollution while monitoring their health. Once the data were
statistically analyzed to correct for other risk factors like smoking,
the results indicated that increased exposure to fine particulate matter
caused by air pollution is linked to health problems like chronic
bronchitis and decreased lung function, as well as premature death. 

Aviation emissions contribute to this health problem, according to a new
study that suggests that airplanes flying at a cruise altitude of around
35,000 feet emit pollutants that contribute to about 8,000 deaths per
year globally. The research, reported online this month
<http://pubs.acs.org/doi/full/10.1021/es101325r>  in the journal
Environmental Science and Technology, provides the first estimate of
premature deaths attributable to aircraft emissions at cruise altitudes.
Aircraft emit nitrogen oxides (NOx) and sulfur oxides (SOx), which react
with gases already existing in the atmosphere to form harmful fine
particulate matter. 

Tracking emissions

Current worldwide regulations target aircraft emissions only up to 3,000
feet. That’s because regulators have assumed that anything emitted above
3,000 feet would be deposited into a part of the atmosphere that has
significantly smoother air, meaning pollutants wouldn’t be affected by
turbulent air that could mix them toward the ground. Thus, even though
90 percent of aircraft fuel is burned at cruise altitudes, only those
pollutants that are emitted during takeoff and landing are regulated by
measuring emissions during tests of newly manufactured engines in
simulated takeoff and landing conditions. 

“Anything above that [altitude] really hasn’t been regulated, and the
goal of this research was to determine whether that was really
justified,” says lead author Steven Barrett, the Charles Stark Draper
Assistant Professor of Aeronautics and Astronautics in MIT’s Department
of Aeronautics and Astronautics.  

To study the effects of cruise emissions, Barrett used a computer model
that combined data about plane trajectories, the amount of fuel burned
during flights and the estimated emissions from those flights. He
combined that with a global atmospheric model that accounts for
air-circulation patterns in different parts of the globe and the effect
of emissions to determine where aviation emissions might cause an
increase in fine particulate matter. He then used data related to
population density and risk of disease in different parts of the world
to determine how the change in particulate matter over certain regions
might affect people on the ground — specifically, whether the air
pollutants would lead to an increased risk of death. 

Analysis of these data revealed that aircraft pollution above North
America and Europe — where air travel is heaviest — adversely impacts
air quality in India and China. That is, even though the amount of fuel
burned by aircraft over India and China accounts for only 10 percent of
the estimated total amount of fuel burned by aircraft across the globe,
the two countries incur nearly half — about 3,500 — of the annual deaths
related to aircraft cruise emissions. The analysis also revealed that
although every country in the Northern Hemisphere experienced some
number of fatalities related to these emissions, almost none of the
countries in the Southern Hemisphere had fatalities.

That’s because the majority of air traffic occurs in the Northern
Hemisphere, where planes emit pollutants at altitudes where high-speed
winds flowing eastward, such as the jet stream, spread emissions to
other continents, according to the study. Part of the reason for the
high percentage of premature deaths in India and China is that these
regions are densely populated and also have high concentrations of
ammonia in their atmosphere as a result of farming. This ammonia reacts
with oxidized NOx and SOx to create fine particulate matter that people
inhale on the ground. Although agriculture is abundant in Europe and
North America, the ammonia levels aren’t as elevated above those
regions. 

Industry reaction

Funded by the UK Research Councils with help from the U.S. Department of
Transportation, the study recommends that cruise emissions be
“explicitly considered” by international policymakers who regulate
aviation engines and fuels. Steve Lott, a spokesman for the
International Air Transport Association, a trade group that represents
230 airlines, says that aviation is “a small part of a big problem,”
particularly when compared to other transportation sources of emissions,
such as those caused by shipping, which a 2007 study linked to 60,000
premature deaths per year.

Lourdes Maurice, the chief scientific and technical adviser for
environment at the Federal Aviation Administration, says that if the
agency can confirm Barrett’s findings through additional research, then
it will work with the Environmental Protection Agency and the
International Civil Aviation Organization to consider appropriate
regulatory action. The FAA will continue to fund research to address
uncertainties highlighted by Barrett’s work, she adds.

Barrett concedes that there are many uncertainties, including how
accurately the model reflects how air travels vertically from high
altitudes to low altitudes. To address this, he is collaborating with
researchers at Harvard to study an isotope of the element beryllium that
is produced naturally at high altitudes and attaches to atmospheric
particles that eventually reach the ground through air or rain.
Researchers have a general idea of how much beryllium is concentrated in
the atmosphere, and Barrett and his colleagues are currently analyzing
ground measurements of the element to quantify the extent to which his
model “gets vertical transport right.”

Barrett is a member of the Partnership for AiR Transportation Noise and
Emissions Reduction (PARTNER), a cooperative research organization that
completed the study. Sponsored by the FAA, NASA and Transport Canada,
PARTNER has its operational headquarters at MIT. 

/Quote

I would like to add that in New South Wales and Victoria we have the
added benefit of Coal Fired Power stations adding to that lung
poisoning.

A few months ago I blogged about the increase in particulate matter
(dust) that I noticed,dramatically increasing as a result of the M7
opening. 

In Germany, all Trucks are forbidden (off the motorways) during daylight
hours.
We can't do much about the carbon soot from the power stations, (apart
from installing additional scrubbing in the stacks) but the trucks, we
could get the trucks off the road.

As for aeroplane carbon, we could just reroute all flights over water
..
(err that was a joke for those that dont grok Koltai humour).


Tom.