Each year, 9 billion tons of carbon, a greenhouse gas, pours into Earth's atmosphere, according to scientific research  . The majority – 7.5 billion tons – comes from energy use and the burning of fossil fuels. Without change, atmospheric carbon amounts are likely to rise, especially in light of predictions that the world's population will swell from 6.5 billion people today to 9 billion by 2050 or after.
Many scientists believe that a reduction of greenhouse gasses is key to halting the rise in global temperatures, and numerous solutions are being researched.
One of those ideas, and the main facet of the Lieberman-Warner Act which ignited a vigorous Congressional debate that derailed the climate change bill until at least 2009, is a market-based approach called carbon cap and trade.
A cap-and-trade system would set ceilings for carbon dioxide emissions that would be imposed on virtually all major industries in the United States. The government would issue permits for each ton of carbon released into the atmosphere by a business. Lieberman-Warner called for a 70 percent reduction in carbon emissions in the U.S. by 2050.
Plants that exceed their regulated limits could purchase carbon credits through a commodities market from industrial operators who released less carbon than permitted.
Industries could also buy allowances from other public or private entities engaged in a so-called offset program. For instance, farmers who plant crops with no-till techniques, which keeps carbon trapped in the ground, could earn carbon credits that they can sell on a market. Such a voluntary program now exists, run by the member-based Chicago Climate Exchange.
One of the Climate, Water and Carbon (CWC) program's core projects focuses on keeping carbon within soil and other terrestrial ecosystems around the world. Researchers will produce methods for monitoring, measuring and verifying the amounts of carbon retained to help fully cultivate a carbon trading program.
The CWC is also sponsoring several seed projects related to carbon trading policies and their affects. One project is looking at accounting measures for the amounts of carbon stored in forests. Research shows that the world's forests currently store about 800 billion tons of carbon in trees and soil.
Another project will look at policies to increase the amount of carbon retained in ecosystems, particularly in Latin America. Others will examine the economics of land use and trapping carbon and another will develop global models to assess how the reduction of forest clearing will impact local economies that rely on the cleared forest land for grazing and farming.
Professor Brent Sohngen, of OSU's Department of Agriculture, Environmental and Development Economics and a CWC leader, describes his project and the storage of carbon in the world's forests (press Play on video at right).
Carbon emissions into the atmosphere are the result of many factors, including oil-based energy systems, the clearing of forests, changes in land use and the production of cement. 
Carbon dioxide in the atmosphere absorbs and reflects back to Earth heat that would otherwise leak out into space, causing planet temperatures to rise.
Current atmospheric measurements find 385 parts per million of carbon in the air. Parts per million is a scale used to measure a substance within one million parts of a gas, liquid or solid.
While 385 might not sound like a lot within a million parts, carbon was only at 280 parts per million at the beginning of the industrial age in the late 18th and early 19th Centuries. During the past 800,000 years or so, atmospheric carbon cycled between 180 and 280 parts per million, making today's 385 number significantly greater than any value in our planet's recent geologic past.
Scientists believe carbon is increasing at a rate of 2 parts per million every year and if the surge continues unabated, global temperatures could rise by four degrees centigrade by 2100, provoking sure-fire climate changes.
One of the CWC core projects headed by Professor Rattan Lal, of OSU's School of Environment and Natural Resources and a CWC leader, will examine how the use and management of farm lands, forests and water along with accompanying policies can keep carbon trapped into Earth's ecosystems and out of the atmosphere.
Researchers will examine how and by how much these practices will offset or balance the cycle of carbon between ecosystems to atmosphere in order to ease abrupt climate changes and the adverse effects that those changes may bring.
Scientists will test a variety of methods to see how much and how easily carbon can be stored in soil, the oceans, within the ground and through forest planting. Adoption of these methods could produce some side benefits too, including improved water quality and more biodiversity.
No-till farming, a long-running experiment at Ohio State, is one such technique with implications going beyond the reduction of atmospheric carbon. If these farming methods were more widely adopted around the world, crop yields would likely increase, helping to feed more than one billion people who currently face food security issues.
Rattan Lal discusses carbon sequestration – also known as carbon farming – and techniques of no-till farming which could eventually help increase global food security (press Play on video at right).
Adoption of a cap and trade program could be one of the most cost effective ways to lessen adverse effects brought on by abrupt climate change. That doesn't mean it's a slam-dunk situation. Issues must be confronted and questions answered to determine if the program is viable.
For instance, if carbon is stored in soil through no-till farming, how permanent would retention be? How can small landowners be convinced to adopt no-till farming techniques and is financial aid available? If forests are set aside for preservation, would loggers just move on to other areas and clear trees? Can stored carbon be measured universally? And can carbon storing policies be developed as an economic package rather than simply as an environmental policy that is more likely to fail?
One of the CWC-sponsored seed projects led by Professor Andy Keeler, of OSU's John Glenn School of Public Affairs and a CWC leader, intends to take on some of those issues. In particular, the project is looking at how carbon trapping efforts in developing countries can impact the reductions of carbon sought by developed countries like the United States. Much of that research will occur in Ecuador.
Many nations are already experimenting with carbon credit trading that was set up in the Kyoto Protocol of 1997. In the treaty, nearly 200 countries, excluding the United States, agreed that 38 industrialized nations would commit to reducing six greenhouse gas emissions. The developed countries committed to lowering emissions by a 5.2 percent based on 1990 levels between 2008 and 2012.
CWC researchers will examine how carbon stored in smaller nations could be traded in the marketplace as offsets in developed countries. And they will scrutinize how the money earned from those offset trades might help boost the economy for people living in less developed countries.
Scientists will also investigate methods for accounting for the uncertainties in measuring carbon storage, the costs of carbon offset transactions and the development of strategies to ensure that an accurate account can be developed for stored carbon that is later lost to the atmosphere.
Andy Keeler talks about how a carbon cap-and-trade system would work along with carbon offsets in the U.S. and developing countries (press Play on video at right).