Earth's delicate climate balance is affected by greenhouse
gases released into the atmosphere.
#4: A hydrogen-based economy could have an unforeseen impact
on the Earth's climate.
may be rancorous political debate about global warming, but
little scientific debate remains. The planet's overall temperature
rose about 1 degree Fahrenheit during the last century. The
phenomenon is well known as the greenhouse effect and it is
the direct result of burning fossil fuels. One degree may
not sound like a lot, but researchers have already documented
significant impacts on agriculture, wildlife, diseases and
weather patterns. And as long as we keep releasing greenhouse
gases into the atmosphere, the warming trend will continue.
reason transitioning to hydrogen fuel is so attractive is
that pure water is its only waste product. What could be more
harmless than pure water? As it turns out, water vapor is
known to have an impact on regional temperatures. As Scientific
American Frontiers has previously
reported, "As soon as officials recognized that terrorists
had hijacked at least four planes on the morning of September
11, 2001, all commercial air traffic was grounded in the U.S.
for three days. The situation provided atmospheric scientists
with the unique opportunity to study how the exhaust from
all those airplanes affects the weather."
Airplane contrails are made of
water vapor -- and can affect local temperatures.
looking at the average daily temperature range for September
11- 13, 2001, and comparing that to the average daily temperature
range for the same days in September over the last 30 years,
climatologists found that the temperature range was about
2 degrees Fahrenheit greater while the planes were grounded.
The scientists hypothesized that the jet exhaust or contrails
act like artificial clouds, simultaneously blocking incoming
solar energy and trapping the heat radiating off the planet's
surface. In this way, jet contrails keep the Earth cooler
during the day and warmer during the nights. Although the
jet contrails' effect was regional and not global, this study
shows how small changes can make measurable differences in
of water vapor help determine the amount of solar
radiation reaching earth. How would wide use of hydrogen
fuel affect this system?
Credit: Warren Gretz
of the complexity involved in climate modeling, no one can
say exactly how transitioning to hydrogen would affect the
planet. While that topic certainly merits further study, we
do know that our continued dependence on carbon-emitting fuels
will continue the warming trend so thoroughly documented over
the last century.
poorly designed hydrogen transition could cause environmental
problems," Lovins concedes in "Twenty Hydrogen Myths." "But
a well-designed one can resolve most of the environmental
problems...without making new ones."
his State of the Union address in 2003, President George Bush
not exactly a darling of the environmental lobby announced
his Hydrogen Fuel Initiative, funding that could ensure that
"the first car driven by a child born today could be powered
by hydrogen, and pollution-free."
Bush talks on a fuel cell-powered cell phone.
Credit: Paul Morse
2004, the Department of Energy awarded $75 million in research
grants for hydrogen research projects. Yet Lovins says some
of the myths he works to dispel are still propagated on the
DOE's own Web site. Lovins maintains that economics above
all else makes the transition to the hydrogen economy an inevitability.
The sooner these myths are dispelled, the sooner we can all
realize our hydrogen hopes.
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