Scotland agrees world's toughest 2020 climate goal

* Scots seek to cut greenhouse gases by 42 percent

* Ambitious goal goes further even than Germany

* Option to scale back if no global deal in December



LONDON, June 24 (Reuters) - Scottish lawmakers on Wednesday backed a binding goal to cut greenhouse gases by 42 percent by 2020 from 1990 levels, edging Germany into second place in a ranking of the most ambitious developed world targets.

Developing countries have demanded that rich nations take the lead in fighting climate change. They have so far been unimpressed with plans which show big gaps must be bridged to agree a global treaty in December to replace the Kyoto Protocol.

Scotland's bill included an option to curb its ambition if no strong global climate deal is reached in six months' time.

Environmental campaigners nevertheless hailed the decision by Scotland, which has ample potential for low-carbon wind power, having derided targets proposed earlier this month by Japan and Russia.

"At least one nation is prepared to aim for climate legislation that follows the science," said Kim Carstensen, head of the Global Climate Initiative of the WWF International environmental group.

Some Scottish lawmakers described the climate bill as the most important since the establishment of the Scottish parliament in 1999.

Britain formally adopted in April a legally-binding target to curb greenhouse gases by 34 percent. [ID:nLM955969] Lawmakers in Scotland have some local autonomy and went a step further than the national parliament. Scotland has a population of 5 million compared with a total British population of 61 million.

China and many developing nations want the rich to cut carbon by at least 40 percent by 2020 to avoid the worst effects of global warming such as droughts, floods and rising seas.

The European Union has agreed a target to cut greenhouse gases by at least 20 percent by 2020, and Germany plans to cut carbon emissions by 40 percent compared with 1990 levels.

Green groups criticised Japan's and Russia's plans annnounced this month to cut emissions by 8 percent and 10-15 percent respectively [ID:nLM399610].