Sir, The European Union carbon trading schemes introduced in 2005, outlined in the article "Carbon trading grunts into life' (April 2), saw limited emissions trading conducted among a handful of large companies, and was used primarily as a training exercise. The second period will fully integrate emissions trading with other commodities, and a whole new set of rules will apply.

The charged and complex debate over how to slow down global warming has become a lot more complicated. Most of the focus in the past few years has centered on imposing caps on greenhouse gas emissions to prod energy users to conserve or switch to nonpolluting technologies.

The Indian automobile industry is on its way towards a cleaner and more energy-efficient future, so what if it is being driven by the government to do so. With the stringent Bharat Stage IV emission norms expected to kick in by the first half of 2010, the ministry of power has now decided to accord energy (read fuel) efficiency ratings to all automobiles manufactured in India.

Italy will achieve its greenhouse gas-cutting targets under the Kyoto protocol by buying carbon credits from Russia, under a deal announced yesterday that could cost the government billions of euros. Italy is expected to miss its Kyoto targets by a total of about 400m to 500m tonnes of carbon dioxide, and will therefore have to make up the shortfall with carbon credits issued by the United Nations. But the government did not say how many credits it would buy under a deal with Carbon Trade and Finance, a joint venture between Russia's Gazprombank and Dresdner Bank.

A potential new weapon in the battle against global warming - to remove carbon from the atmosphere by locking it up permanently in soil minerals - is being developed at Newcastle University in the UK. When plants absorb carbon dioxide from the atmosphere during photosynthesis, they use some of the carbon to grow. But most is pumped through the roots into the earth around them and then escapes back into the atmosphere or groundwater.

Even allowing for the low expectations we bring to any lame duck president's final state of the Union address

18 US States Sue EPA Over Greenhouse Gas Pollution US: April 4, 2008 WASHINGTON - Eighteen states sued the US Environmental Protection Agency on Wednesday for failing to limit greenhouse gas emissions from new cars and trucks, one year after the Supreme Court ruled that the agency had the power to do so. The suit seeks EPA's response to the high court's April 2, 2007, ruling, a landmark decision seen as a sharp defeat for the Bush administration's policy on climate change.

The EU's fledgling market for carbon yesterday shrugged off provisional figures showing that Europe's big polluters emitted lower levels of carbon dioxide than allowed last year. The price of carbon permits for 2008 rose by 4% as investors took the view that tighter emissions rules that came into effect this year will mean permit shortages in the future.

Australia began pumping carbon dioxide underground on Wednesday using an experimental technology that aims to reduce greenhouse gas emissions by locking dangerous gases deep in the earth.