CO2 Rising Ever Faster

Tuesday, May 29th, 2007--

The rate of carbon dioxide (CO2) emissions is accelerating all over the world, according to a paper in the journal Proceedings of the National Academy of Sciences. In fact, CO2 emissions are growing faster than the most extreme forecasts by the Intergovernmental Panel on Climate Change (IPCC).

From 1990-1999, the amount of carbon dioxide released into the atmosphere increased by 1.1 percent; from 2000-2004, the emissions growth rate tripled to three percent each year.

Most of the CO2 in the atmosphere is released when coal, oil and natural gas is burnt for energy. But other contributors exist—cement-production, for example, which involves burning calcium carbonate to expel carbon, accounts for about three percent of the total emissions.

Chris Field, director of the Carnegie Institution’s department of global ecology at Stanford in CA, and colleagues, including Gregg Marland, a researcher in the environmental sciences division at the Oak Ridge National Laboratory in Oak Ridge, TN developed an equation that helps explain what is causing the acceleration in emissions.

The researchers looked at four factors: population, individual wealth (gross domestic product—GDP—per person), energy efficiency of the economy (energy per unit of GDP) and how much C02 is produced per unit of energy. Coal, for example, produces more carbon dioxide per unit of energy than any other major energy source, says Marland.

“The conclusion is that CO2 is going up faster than anyone expected,” Marland says. The IPCC predicted a slower growth rate, but the assumption was based on the idea that we would move towards energy sources that are more efficient—sources that produce less CO2 per unit of energy, Marland says. The other assumption was that our economies would become more efficient, requiring less energy for the same amount of product.

Historical data backed up these assumptions: “The trend had been downward for the last twenty years or more, and they assumed those [variables] would continue to decline,” Marland explains.

Why have these factors—the amount of CO2 emitted per unit of energy and the amount of energy it takes to run the economy—started increasing in recent years? “They’ve turned up for a couple of reasons, I think, and part of it is that there is only so much hydropower you can establish, the limits on nuclear power...,” says Marland. The other key factor is that America and other developed nations are moving production to less developed nations. Marland says: “We’re moving our CO2 emissions offshore. But by moving things to countries like China, we move the energy source to more coal, for example.”

The U.S. may be decreasing domestic energy efficiency, but if it’s moving production to countries like India and China that use less efficient energy sources, global emissions will accelerate.

The data show that no region has decreased the rate of carbon emissions in the last four years. In developed countries, like the United States, increase in population and wealth contributed to the increased output of CO2. This type of growth is important to the calculation, Marland says, “but it’s not the whole story.”

What did you think of the story? Send us some feedback.

--Flora Lichtman

Sources

Gregg Marland
Environmental Sciences Division Oak Ridge National Laboratory Oak Ridge, TN

Tools:

Elsewhere on sciencefriday.com

US Mortality Likely To Rise As Climate Changes
Increases in extreme hot weather due to global warming may lead to increased mortality. Which cities will be hit hardest?

Can't see the Tundra for the Trees
A study in Canada revealed that the tundra is shrinking in response to global warming.

Ancient Dna Offers Clues About Climate Change
What can ancient DNA can tell us about the effects of climate change?

Live Earth Concerts Kick Off Worldwide
Can music stop global warming? We'll talk with some of the organizers of the 'Live Earth' concerts scheduled for tomorrow across the globe.

Biofuels Update
Join Ira Flatow in this hour of Science Friday for a discussion of alternative energy and biofuels.

Global Climate Change Update
Scientists say carbon dioxide levels in our atmosphere are shooting up faster than anyone predicted. What does that mean for climate change -- and for plans to limit carbon emissions?

The World Without Us
What would the world be like if humans were to disappear from the planet?

Green Energy at Google
In this segment, Ira talks with the 'alternative energy czar' for web giant Google about the company's plan to give a boost to green energy.

Bali Climate Conference Wrap-up
Last Saturday, delegates to a UN climate conference agreed to a 'roadmap' that would guide how the international community approaches the issue of global warming in the years ahead. But where does that roadmap lead?

Lester Brown - Plan B 3.0
Ira talks with Lester Brown of the Earth Policy Institute about the environmental problems facing the globe, and what can be done to take action to fix them.

Hurricanes, Climate and Weather
Researchers from the American Meteorological Society met this week in New Orleans, site of the Hurricane Katrina disaster just years ago. How much is known about the effects of climate change on hurricanes?

Orbiting Carbon Observatory
NASA plans to launch an orbiting satellite observatory to map the carbon dioxide in the Earth's atmosphere.

Solar Energy Update
Solar power is often offered as one of the most promising forms of renewable energy. But how close is solar power to becoming a major player in energy production?

Your Feedback: Science Election Issues
We want to hear your thoughts on the most important science-related issues in the coming election campaign. Call in, or email your top issues to vote@sciencefriday.com.

Federal Government and Science
In this hour, Ira and guests look at ways to strengthen science in the federal government -- including making sure the president gets sound science advice, ensuring that scientists can communicate their findings, and encouraging Congress to tackle tough s

Antarctic Glaciers Moving to the Sea
Glaciers in a remote part of Antarctica appear to be speeding up their slide towards the sea. We'll talk with a researcher trying to figure out why.

Solar Power Scales Up
Increasingly, individuals are adding solar panels to their homes and businesses. But is solar technology ready to provide power on a utility power plant scale?

Cities Cutting Energy Use
How are cities around the world taking steps to cut energy use? Ira talks with a journalist who looked at the nine different approaches of nine different cities to the energy problem.

New U.S. Climate Change Goals?
This week, President Bush announced a new set of national goals related to climate change and called for a stop to growth in greenhouse gas emissions by 2025. We'll talk about the goals proposed by the White House, and why some say they don't go far enoug

Calculating Your Carbon
How large is your 'carbon footprint' -- the amount you contribute to greenhouse gas emissions? We'll talk to a researcher looking at energy usage around the country, from homeless people to the rich and famous.

Climate Change Legislation Fails in Senate
This week, the US Senate took up debate on proposed climate change legislation -- but the bill failed to win the needed number of votes to avoid a filibuster and was pulled from the floor.