QUEEN’S ROAD:.Greenhouse gases originate in many places, besides industries. On a global scale, the four key and dangerous greenhouse gases are emitted by:
Carbon dioxide (CO2) Fossil fuel use is the primary source of CO2.
The No 1 greenhouse gas is CO2. It accounts for close to 60 per cent of all such gases, mainly from burning fossil fuels. All industries have used such fuels---diesel, petrol, coal, natural gas---since the start of the industrial revolution.
The way people use land is also contributing to a rise in CO2. The Amazon forests of Brazil are important for the overall ecology of the planet. The air above the Amazon is rich in ‘flying rivers,’ the term natives use for the moisture that circulates like a river.
Deforestation has had crushing consequences for the planet. But the silver lining is that prudent land use and reforestation can remove CO2 from the atmosphere.
Methane (CH4)
Agriculture, waste accumulation, and energy use contribute to CH4 emissions. Methane is a deadly gas produced and released in many ways. Thawing permafrost from the glacial regions is one. Thick layers of snow in the poles have prevented methane from escaping into the atmosphere. Methane is found beneath the earth’s surface. It escapes when snow melts and the bare earth is exposed.
This is one of the reasons why snow in the poles should not be allowed to melt. The other reason is that the water from such melting floods our plains and the seas.Garbage landfills are another source of methane.
They hold the waste we generate every day. When this decays, not only does it give out a foul smell, but it also generates methane. That is why we must segregate our waste and compost all our organic waste like they do in the villages. Composting traps the methane in the ground and produces valuable natural nutrient-rich fertiliser.
Nitrous oxide (N2O)
Agriculture---especially industrial agriculture that uses massive amounts of fertiliser---is the primary source of N2O emissions. The global food system is responsible for up to a third of all human-caused greenhouse-gas emissions, according to the Consultative Group on International Agricultural Research (CGIAR), a partnership of 15 research centres from around the world.
CGIAR says reducing the agriculture carbon footprint is central to limiting climate change. Perhaps farmers across the globe will have to switch to organic farming and more climate-hardy crops.
Sonja Vermeulen, plant scientist at the University of Copenhagen in Denmark and co-author of a study, has examined for the first time carbon emissions for all stages of the global food system.
Using estimates from 2005, 2007 and 2008, she and her team have found that agricultural production is responsible for a lion’s share of greenhouse-gas emissions, releasing up to 12,000 mega tonnes of carbon dioxide, or up to 86 per cent of all food-related anthropogenic (human-generated) greenhouse gases.
Next comes fertiliser manufacture, which releases up to 575 mega tonnes, followed by refrigeration, which emits 490 mega tonnes. The team found that the food system as a whole released 9,800-16,900 mega tonnes of carbon dioxide equivalent in 2008. The figures for current times will be mind bogglingly higher.
Fluorinated gases (F-gases)
Industrial processes, refrigeration, and the use of a variety of consumer products contribute to emissions of F-gases. Fluorinated gases have no natural sources and only come from human-related activities. Even small atmospheric concentrations can have large effects on global temperatures. They also have long lifetimes, in some cases lasting thousands of years. They are well-mixed in the atmosphere and spread after emitted.
Fluorinated gases are removed only when they are destroyed by sunlight in the far upper atmosphere. Attempts to motivate countries to reduce F-gases have found success. The time has come for nations to commit to the reductions of other greenhouse gases.
The author is the founder of Green Dreams for the Planet, an NGO. He is a certified climate leader with the Climate Reality Corps, an Al Gore network.
He can be reached at CBRamkumar@GreenDreams.Vision