A recent research
published
in Oxford Open Climate Change suggests that lowering greenhouse gas
emissions won't be the only tactic mankind takes to combat climate change.
This is the result of a study conducted by researcher James Hansen using
climatic data.
Since the 1800s, scientists have been aware that both natural and man-made
increases in the concentration of greenhouse gases cause the Earth's surface
to warm. These gases absorb infrared light. One of the first scientists to
investigate global warming, Roger Revelle, claimed in 1965 that
industrialization entailed humans engaging in a "vast geophysical
experiment" since burning fossil fuels released carbon dioxide (CO2) into
the atmosphere. Currently, CO2 levels are higher than they have been in
millions of years.
Climate responsiveness
The amount that the global temperature will climb for a given increase in
CO2 is a long-standing question. According to a 1979 research published by
the US National Academy of Sciences, global warming of 1.5 to 4.5°C would
probably result from doubling atmospheric CO2 when ice sheets were frozen.
This was a wide range, and there was also doubt regarding the contribution
of Earth's enormous ocean to the warming delay.
Based on updated paleoclimate data, this new study reassesses climate
sensitivity and concludes that it is more sensitive than previously thought.
Their highest estimate of 4.8°C global warming with doubled CO2 is far
higher than the UN Intergovernmental Panel on Climate Change's best estimate
of 3°C.
Airborne Parts
The scientists also come to the conclusion that the cooling impact of
aerosols—fine airborne particles produced by humans—has largely countered
the predicted warming caused by greenhouse gases during the previous
century. Due to worldwide limitations on ship-related aerosol emissions and
decreased air pollution in China, the quantity of aerosols has decreased
since 2010. Since particle air pollution kills several million people
annually and negatively impacts the health of many more, the reduction of
aerosols is favorable for human health.
Aerosol cooling had concealed greenhouse gas warming, but aerosol decline
is now starting to reveal it. The authors have referred to the aerosol
cooling for a long time as a "Faustian bargain" since greater warming is the
price that must be paid until air pollution is finally reduced by
humans.
According to this new research, global warming will accelerate after 2010
and surpass natural climatic variability. In the decades that follow 2010,
it is expected that the 0.18°C per decade global warming pace from 1970 to
2010 would rise to at least 0.27°C per decade. Consequently, we will surpass
the 1.5°C global warming threshold this decade and the 2°C threshold in the
next two decades.
Regulation
Hansen summarizes his viewpoint—which is informed by decades of experience
attempting to influence government policies—in the concluding section.
First, he thinks that in order to accomplish a quick phasedown of CO2
emissions, contemporary nuclear power must be supported in addition to
renewable energy, and a growing domestic carbon charge with a border tariff
on items from countries without a carbon price.
Secondly, he contends that poor countries need assistance from the West,
which is mostly to blame for climate change, in order to attain energy
pathways that are compatible with a favorable environment for all.
Third, Hansen contends that despite these efforts, global warming will
still have harmful effects and that we should continue researching and
developing short-term, deliberate measures to correct the massive energy
imbalance that now exists on Earth.
Ten years ago, Hansen reported that there was a 0.6 W/m2 (watts per square
meter) energy imbalance on Earth. Incoming energy (solar radiation received)
exceeded outgoing energy (heat radiation to space) by a significant amount.
This surplus, the direct source of global warming, is the same as 400,000
Hiroshima atomic bombs detonated every day, with the majority of the energy
released into the ocean. Now, the imbalance has risen to around 1.2 W/m2,
primarily due to decreased aerosols.
Later this century, this massive imbalance is anticipated to shut down
overturning ocean circulations and create high, fast rising sea levels. It
is also the primary source of accelerated global warming and increasing
melting of polar ice.
The study makes the case that taking such action is necessary to prevent
the larger geotransformation that would result from doing nothing. Possible
interventions include spraying salty ocean water by unmanned sailboats in
areas vulnerable to cloud seeding, and injecting aerosols into the
stratosphere (for which volcanoes offer pertinent, although insufficient,
test cases).
In western democracies, particularly in the US, there is an underlying
issue that Hansen proposes young people concentrate on: "The ideal of one
person/one vote has been replaced by one dollar/one vote," he asserted.
"Political influence may be bought by certain financial interests, such as
the chemical, food, timber, and fossil fuel industries. It is understandable
why the climate is out of control, why environmental toxicity is eradicating
pollinators and other insects, why forests are being mishandled, and why
agriculture is being developed for profit rather than for human nourishment
and welfare."
"We live on a planet with a climate characterized by delayed response,
which is a recipe for intergenerational injustice," Hansen said. "Young
people need to understand this situation and the actions needed to assure a
bright future for themselves and their children."
Provided by
Oxford University Press
