Chickens and pigs around the world are helping to reduce global warming by producing less methane compared to cows and sheep. Methane, a powerful greenhouse gas, is often overlooked in comparison to carbon dioxide but is crucial in the fight against climate change. Government policies and a UN-supported emission credit system are benefiting investors, farmers, and large polluters by allowing them to offset their greenhouse gas emissions, particularly carbon dioxide. Methane is much more effective at trapping heat in the atmosphere than carbon dioxide and can be easily captured from animal waste, landfills, coal mines, or leaky natural gas pipes. "A fifth of all greenhouse gas-induced global warming has been attributed to methane since pre-industrial times," stated climate scientist Paul Fraser of Australia. Methane levels in the atmosphere have risen significantly since 1750, surpassing the natural range of the past 650,000 years according to the UN's climate panel. Human activities are primarily responsible for this increase, particularly in countries like Australia where ruminant farm animals release large amounts of methane. The panel will be addressing ways to reduce methane and other greenhouse gas emissions in a major report on climate change mitigation to be released in Bangkok in early May. "It has been suggested that reducing methane emissions may be more cost-effective than reducing carbon dioxide emissions," noted Bill Hare, climate policy director for Greenpeace and a lead author of the mitigation report. He mentioned that in the United States, policy discussions have largely focused on methane rather than more challenging issues like CO2 emissions from coal. This is because capturing methane from sources like landfills, mines, and fossil fuel production or natural gas lines is relatively simple and economically viable. Methane, a key component of natural gas, can be used to generate power. Hare noted that agriculture presents a greater challenge, especially in regards to methane emissions from livestock and rice agriculture, where changing practices may require longer time scales compared to industrial areas. It is a matter of finding the right balance. Rice paddies and other irrigated crops, along with natural wetlands, release significant amounts of methane. Additionally, large quantities of methane are stored in sub-polar regions under ice, in permafrost, and under the sea. There are various potential solutions to reduce methane emissions, such as additives for livestock and transitioning from intensive feedlots to range-fed animals. Changing the timing and method of flooding rice paddies could also help mitigate methane emissions. Despite methane levels stabilizing around 1999, the amount of methane in the atmosphere remains constant for now, according to Fraser, who leads Australia's government-funded Commonwealth Scientific and Industrial Research Organisation's Changing Atmosphere Research Group. This is believed to occur because the decrease in tropical wetlands is offsetting an increase in emissions from the oil and gas industry. The duration of this phenomenon is uncertain. "Many believe that methane levels will eventually rise again due to the global demand for natural gas, rice, and cattle," Fraser commented. This is why chicken manure and pig waste are in high demand. The Clean Development Mechanism under the UN's Kyoto Protocol allows wealthy countries to meet their emission targets by funding projects that reduce greenhouse gases in developing nations, in exchange for carbon credits. This has led to significant investments in large pig farms in South America and poultry farms in India. The waste from these farms is processed in digesters to extract methane, which is then used to generate electricity or burned to create CO2. This method is seen as a lesser evil in terms of greenhouse gas emissions. Interest in these types of projects is growing, according to N Yuvaraj Dinesh Babu from the Singapore-based Carbon Exchange. The Kyoto system of emissions credits has been popular, with the UN Framework Convention on Climate Change approving many methane-abatement projects in recent years and considering more. However, Stephan Singer from the conservation group WWF believes this is not the complete solution. He suggests that more attention should be focused on controlling carbon dioxide emissions and the sources of methane that are harder to control. Only around 50 percent of methane emissions are currently being controlled, specifically from landfills, coal mines, and the oil and gas industry, according to Singer, who leads WWF's European Energy and Climate Policy Unit. He is concerned about the increasing methane emissions from ruminants, particularly due to the rising beef consumption in a wealthier world. The Western diet has a significant impact on the environment. In the US, cattle release about 5.5 million tonnes of methane annually, making up 20 percent of the country's methane emissions, as reported by the Environmental Protection Agency. In New Zealand, around half of all greenhouse gas emissions come from agriculture. Singer is most concerned about a sudden release of methane from sub-polar permafrost or methane hydrate deposits under the sea. While this has not happened yet, some scientists believe it could happen in a warmer climate. Singer believes that if methane hydrates were to leak, it would be catastrophic.