What is the goal of the conference?
The main goal of the 21st Conference of
Parties is to try to limit the global temperature
increase over pre-industrial levels to
2 degrees Celsius (3.6 degrees Fahrenheit).
If temperatures rise above that threshold,
climatologists say, the damage will be
severe. A rise in sea level of at least several
feet will inundate many coastal cities,
while huge swaths of the world will be
subjected to record heat waves, drought,
floods, and famine. To avoid this fate,
countries would have to collectively slash
carbon dioxide emissions to below 40 billion
tons a year by 2030; currently the
world is on track to emit roughly 59 billion
tons a year by 2030. But with the
effects of 1-degree global warming already
evident—including altered weather patterns
and melting glaciers and sea ice—even reluctant nations like
China appear ready to enter into a binding international agreement
that would set emissions limits for each country. “We’re not
in a world of business as usual anymore,” says U.N. climate chief
Christiana Figueres. “We’re in a world of business as urgent.”
Why didn’t nations act earlier?
Cutting emissions required accepting a lot of immediate economic
pain for abstract future gain, which human beings resist. In Kyoto
in 1997, delegates secured a legally binding pact to address climate
change. But the U.S. Congress refused to ratify the agreement, so it
was not binding. A total of 37 industrialized countries did pledge
to cut emissions by an average of 5 percent against 1990 levels by
2012, but 16 of the nations failed to hit their targets. There was
a greater sense of urgency at Copenhagen in 2009, but the global
financial crisis left countries reluctant to commit to reductions that
could dampen economic growth. In
the end, delegates were able to come
up with only a weak, nonbinding
commitment to “take note” of the
2-degree ceiling. The run-up to Paris
has been very different.
How so?
This time around, each of the 195
countries and the EU have been asked
to submit a specific, individual reduction
in emissions they intend to make
by 2030. Almost 150 countries have
thus far submitted targets with sizable
reductions. President Obama has
committed the U.S. to a reduction
of between 26 and 28 percent from
2005 levels by 2025. The cuts will
be made not by reducing Americans’
overall energy use, but by burning
far less coal, doubling the amount of
electricity generated by solar and wind
power, and imposing stricter fuel efficiency
and greenhouse gas standards
on medium- and heavy-duty vehicles.
China, which is currently dealing with
uncontrollable smog levels in its cities,
has pledged that its carbon emissions
will peak by 2030, and that renewable
energy will account for 20 percent of
electricity consumption by that year.
Who could ruin the deal?
Poorer, less developed countries that
face serious consequences from climate
change have threatened to walk out
of the conference. They are demanding
a pledge from richer, industrialized
nations to provide $100 billion a year
to help them adapt to rising seas and
hotter temperatures. An argument is
also brewing between France and the
Obama administration, which doesn’t
want the pact to be legally binding.
For a binding treaty, the White House
would need ratification from the Republican-led Congress, which
it almost certainly would not get. Even if delegates did manage
to overcome these disputes and secure a universal agreement, the
current pledges submitted would still result in warming of between
2.7 and 3.5 degrees C. At best, says Tim Gore of the global charity
Oxfam, the conference is seeking an agreement that would “only
take us from a 4-degree catastrophe to a 3-degree disaster.”
Is 2 degrees a lost cause?
Many scientists believe we’ve already emitted enough greenhouse
gases to lock in a 2-degree Celsius rise, since those gases will
continue to have a warming effect for up to a century. And total
emissions are likely to continue to rise, with India insisting it has
to double its coal production by 2020 to help lift its massive and
rapidly growing population of 1.3 billion out of poverty. “Barring
some technological miracle, we’ll probably blow right past it,”
says climate scientist Ray Pierrehumbert.
What then?
Some scientists and technologists,
including Bill Gates, argue
that innovation is our best hope.
Researchers could focus on developing
an alternative form of energy
production that produces no greenhouse
gases. Another possibility
is carbon capture and storage—a
still-unproven technology in which
power plants pump their carbon
emissions into the ocean or underground
reservoirs, where the gases
can’t trap the sun’s heat. A much
riskier enterprise is geo-engineering.
(See box.) But given the uncertainty
of innovation, the Paris climate
summit will still be a critical test
of the world’s seriousness about
responding to climate change.
“The key for Paris,” says President
Obama, “is just to make sure that
everybody is locked in, saying,
‘We’re going to do this.’”
Hacking our planet’s atmosphere
As climatologists resign themselves to the inevitability
of major warming, some are turning their
attention to “geo-engineering”—using technology
to artificially cool the climate to compensate for the
greenhouse effect. One team has proposed erecting
a giant mirror in outer space to reflect the sun’s rays
away from the Earth; another has suggested covering
Greenland’s ice sheets in a shiny blanket that
would reflect solar radiation. Perhaps the most feasible
proposal is to use aircraft or powerful missiles to
spray out large quantities of sulfur dioxide particles
at high altitude, creating a sulfur cloud that reflects
solar radiation. But geo-engineering is highly controversial.
Some scientists warn that disrupting the
enormously complex system we call climate would
have unpredictable and potentially catastrophic
results: It might get cooler over one continent, but
hotter elsewhere, while storm and rainfall patterns
could change dramatically. Matt Watson, a member
of a British team researching geo-engineering,
admits that it’s impossible to predict how intervening
in the climate could affect the planet. “Personally, I
find this stuff terrifying,” Watson said.
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