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Cooler Planet Scientists are cooking up solutions based on
current technology that they say they could dramatically turn down the heat of
global warming over the next 50 years. Innovations such as
cheaper wind power, gas-electric hybrid and gas cards that generate funds for
climate-change projects already are available. Introducing them across the
nation could put a dent in the growth of greenhouse gases that are warming the
planet, scientists say. The concentration of carbon dioxide--a
potent greenhouse gas--is likely to double before the end of the century, the
United States says. Scientists say further warming is inevitable as greenhouse
gas emissions climb but that the worse effects can still be avoided.
"The question now is not ’whether to adapt’ but ’how to adapt’" says a
2004 U.N. report on climate change. The solutions, says experts,
must come from action by politicians, business people, scientists and
individuals. Over the next century, power could be derived from sources that
release less carbon dioxide into the atmosphere such as nuclear fusion, hydrogen
fuel cells and more efficient combustion engines(内燃机). Scientists:
Technology already exists Technology is a crucial component
to meeting the challenge of global warming, say climate researchers and policy
experts. "You need technology;" says Elliot Diringer,
international strategies director with the Pew Center on Global Climate Change.
"There’s no question about that. The question is, ’What is the most efficient
way to not only generate the technology but get it deployed.’"
The intergovernmental Panel on Climate Change, a U.N. body issuing regular
assessments on the climate, says innovation has advanced faster than expected.
It estimates technological improvements could reduce greenhouse gas emissions
below 2,000 levels within 20 years and avert even more risky levels of such
concentrations. The IPCC has estimated that technological
improvements could sometime between 2010 and 2020 reduce greenhouse gas
emissions to levels below those in the year 2000. "We need to
move as fast as we can," Diringer says. "The longer we wait to take
concerted action, the greater the impact will be... the more it will cost to
achieve the reduction." Technology with the greatest potential
to reduce greenhouse gas emissions already exists, says Princeton University
scientists Stephen Pacala and Robert Socolow in a 2004 study published in the
journal Science. Improving efficiency and conservations could
reduce billions of tons in atmospheric emissions of greenhouse gases each year.
Improvements such as efficient engineering, better gas mileage(英里里程) and new
fuel sources for vehicle and power plants have the potential to halt growth of
emissions by around 2050, according to the study. "It is
important not to become diverted by the possibility of revolutionary
technology," the Princeton authors write in Science. "Humanity can solve
the carbon and climate problem in the first half of this century simply by
increasing we already know how to do." The scientists picked
seven actions that they say could make the climate stable by 2054. They focused
on technology already in place that simply needs to be expanded-- a
lot. Cars are an easy target. Each gallon (加仑) of gas burned
gives off about 20 pounds of carbon dioxide into the atmosphere, according to
the Environmental Protection Agency. That’s a lot of carbon for the 2 billion
cars that may be on the road in 2054, nearly four times the number today, the
authors report. The Science article suggests that doubling the
average fuel efficiency of cars from 30 miles per gallon today to 60, switching
to wind-generated hydrogen fuels or halving the annual number of miles traveled
per car to 5,000 could reduce carbon dioxide emissions. The savings would
provide one-seventh of the total cuts needed to make U.S. emissions stable, the
article states. In addition, scientists are watching plenty of
other technologies being developed to make emissions stable. Carbon
storage Burying carbon dioxide allows fossil fuel companies
to continue pumping oil while reducing greenhouse emissions. The United Nations
estimates by 2050 it should be possible to store half of the increasing global
emissions in underground reservoirs (水库) at reasonable prices.
The U.S. government already has started a test project at a West Virginia
coal power plant. The energy company BP sends 1 million tons of carbon dioxide
each year beneath the sands of Sahara desert at one of its facilities in
Algeria. These carbon-reducing projects send millions of tons of
carbon dioxide gas into underground geologic formations such as gas beds now
filled with water, natural gas or oil. The risks of such
techniques include leakage of carbon dioxide from underground reservoirs that
may endanger human life and environment. Scientists are studying techniques to
find which rock formations permanently store gases such as carbon
dioxide. Renewable energy Renewable power is a major
facet of reducing global warming emissions, according to the United
Nations. Because most renewable energy sources--wind, ocean
tides, solar, biomass fuel--emit less carbon dioxide into the atmosphere than
they absorb, they do not add to climate change. The share of renewable in the
world energy supply accounts for at least 14 percent of the total, the United
Nations estimates. The price of these renewable fuels and
technology is plummeting as demand grows and hardware improves. "Green" tariffs,
already introduced in some European countries, guarantee premium prices for
energy derived from renewable sources. States such as New York
and California also require utilities to generate a fraction of their energy
supply from renewable. Trading carbon Carbon emissions
trading is designed to make global warming prevention affordable, according to
the U.N. Convention on Climate Change. Under the Kyoto
Agreement, participating countries agree to emit a certain amount of carbon. If
a country cannot afford to meet its carbon emissions limit, it can buy "credits"
from a country that has produced less than its allotted amount.
Although critics say there are significant problems under the Kyoto
system, the United Nations says emissions trading allows countries gradually to
eliminate carbon dioxide while preventing some economic hardships of reducing
emissions growth. Corporate action Companies also an:
devising ways for business and individuals to offset greenhouse emissions.
Oregon-based Climate Neutral Network says it soon will offer air travelers
access to "Cool Class" air travel in which a portion of airline fares,
negotiated through contracts with different companies, are invested in ways to
reduce greenhouse emissions. We are not able to prevent the bad effects of the global warming.