Methane leaks during production may offset climate benefits of natural gas.

Natural-gas operations could leak enough methane to tarnish their clean image. (Editorial)

Buses spew clouds of black exhaust fumes in Mexico City while, in India, wood burnt in rudimentary stoves fills houses with sooty smoke. Methane leaks from gas pipelines in Russia and rice paddies in China, eventually breaking down in sunlight and contributing to the production of smog and ozone. In each of these cases, simple steps to curb air pollution would promote public health; scaled up, they may offer the only realistic way to tame global warming over the next few decades.

Tropospheric ozone and black carbon (BC) contribute to both degraded air quality and global warming. We considered ~400 emission control measures to reduce these pollutants by using current technology and experience. We identified 14 measures targeting methane and BC emissions that reduce projected global mean warming ~0.5°C by 2050. This strategy avoids 0.7 to 4.7 million annual premature deaths from outdoor air pollution and increases annual crop yields by 30 to 135 million metric tons due to ozone reductions in 2030 and beyond.

China aims to produce 30 billion cubic metres of coalbed methane gas in 2015, more than triple the about 9 bcm produced in 2010, the National Development and Reform Commission said as part of a fiv

Developed for troops serving on glaciers high in the Himalayas, the non-flushing “bio-digester” toilet made by India’s top defence research body is now being offered to companies and poorer states.

Rice paddies have been identified as major methane (CH4) source induced by human activities. As a major rice production region in Northern China, the rice paddies in the Three-Rivers Plain (TRP) have experienced large changes in spatial distribution over the recent 20 years (from 1990 to 2010). Consequently, accurate estimation and characterization of spatiotemporal patterns of CH4 emissions from rice paddies has become an pressing issue for assessing the environmental impacts of agroecosystems, and further making GHG mitigation strategies at regional or global levels.

After CNG, the national capital is all set to run its public transport fleet on biogas. Ambitious as it may sound, but Delhi plans to run its buses on biogas. In collaboration with the Swedish government, the Union Ministry of New and Renewable Energy plans to set up a biogas plant inside Kesopur Sewage Treatment Plant (STP) complex in West Delhi. The plant will receive raw gas emitted by the STP and upgrade it so that it can be used to propel vehicles.

India's energy security has come under an alarming pressure from rising dependence on imported oil, regulatory uncertainty and opaque gas pricing policies, according to a FICCI-Ernst & Young re

The depiction of farming's greenhouse-gas footprint (estimated at 30.9% of total emissions) is derived from a 2007 report that used data from 2004 (Nature 479, 279; 2011). But relative estimates of emissions from different sources have altered appreciably since then, largely because fossil-fuel usage and cement production for building have both escalated. (Correspondence)