Page 533 - Environment: The Science Behind the Stories

carbon offsets could become an important means of mitigat-
ing climate change. Place space
mirrors in orbit
Corporations are going carbon-neutral

Carbon offsets are a major route toward carbon-neutrality Inject sulfate
among businesses and corporations seeking to make their aerosols into
practices more sustainable (pp. 173–174), but corporations stratosphere
also can find ways to reduce their carbon footprints directly.
An excellent example is Pearson Education, the publisher of Capture carbon Restore
your textbook! with artificial trees forests Seed clouds with
seawater mist
In 2009 Pearson achieved carbon-neutrality after a con-
certed two-year effort (p. 173). Pearson reduced its energy
consumption and carbon footprint directly by 12% by upgrad- Erect land-based
ing buildings for energy efficiency, designing more efficient mirrors
computer servers, reducing the number of vehicles in its Store carbon
underground
fleets, increasing the proportion of hybrid vehicles, and cut-
ting back on employee business travel while enhancing the
use of video conferencing. Pearson eliminated a further 47% Fertilize ocean with iron
of its emissions by purchasing clean renewable energy instead to spur plankton blooms
of fossil fuel energy and by installing large solar panel arrays
at two of its sites in New Jersey and a wind turbine at a Min-
nesota site. To offset the remaining 41% of its emissions, the Figure 18.32 Geoengineering proposals seek to cool the
company is funding a number of programs to preserve forest climate by removing carbon dioxide from the air or reflecting
and replant trees in various areas of the world, from England sunlight away from Earth. However, most geoengineering ideas
to Costa Rica. are untested, would take years to develop, may not work well, or
might cause undesirable side effects. Thus, they are not a substi-
tute for reducing emissions.
Should we engineer the climate?

What if all our efforts to reduce emissions are not adequate
to rein in climate change? As severe climate change begins back-up plan. Respected researchers and scientific institutions
looking more and more likely, some scientists and engineers are beginning to assess the risks and benefits of geoengineer-
are reluctantly considering drastic, assertive steps to alter ing options, so that we can be ready to take well-informed
Earth’s climate in a last-ditch attempt to reverse global warm- action if climate change becomes severe enough to justify it.
ing—an approach called geoengineering (Figure 18.32).
One geoengineering approach would be to suck carbon You can address climate change
dioxide out of the air. For example, we might enhance photo-
synthesis in natural systems by planting trees or by fertilizing National policies, international treaties, emissions trad-
ocean phytoplankton with nutrients like iron. A more high- ing programs, corporate actions, and technological inno-
tech method would be to design “artificial trees,” structures vations—and perhaps even geoengineering—will all play
that chemically filter CO from the air. roles in mitigating climate change. But in the end, the most
2
A second geoengineering approach would be to block influential factor may be the collective decisions of mil-
sunlight before it reaches Earth, thus cooling the planet. We lions of regular people. Just as we each have an ecologi-
might deflect sunlight by injecting sulfates or other fine dust cal footprint (pp. 22–23), we each have a carbon footprint
particles into the stratosphere, by seeding clouds with seawa- that expresses the amount of carbon we are responsible for
ter, or by deploying fleets of reflecting mirrors on land, at sea, emitting. To help reduce emissions, each of us can take
or in orbit in space. steps in our everyday lives—from turning off lights and
Scientists have long been reluctant even to discuss the choosing energy-efficient appliances, to eating a less meat-
notion of geoengineering. The potential methods are techni- oriented diet, to deciding where to live and how to get to
cally daunting and would take years or decades to develop, and work.
some could pose unforeseen environmental risks. Moreover, College students are vital to driving the personal and soci-
blocking sunlight does not reduce greenhouse gas concen- etal changes needed to reduce carbon footprints and address
trations, so ocean acidification would continue. In addition, climate change—both through everyday lifestyle choices
many experts are wary of promulgating hope for easy techno- and through lobbying and activism. Today a groundswell of
logical fixes, lest politicians lose incentive to develop policy interest is sweeping across campuses, and many students are
to reduce emissions. pressing their administrations to seek carbon-neutrality or to
However, as climate change intensifies, more scientists divest from fossil fuel investments and promote renewable
are becoming willing to contemplate geoengineering as a energy (pp. 34–36, 673–683). Campus action on climate
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