FACTBOX: Greenhouse gas goals proposed at U.N. climate talks

OSLO (Reuters) - Following are proposals for greenhouse gas targets to be considered at U.N talks on a new climate treaty in Bonn, Germany, from March 29-April 8.

The talks are the first this year in a two-year push to agree a new U.N. climate treaty in Copenhagen in December 2009. The following factbox is based on ideas submitted to the United Nations.

LONG-TERM GOALS

"There is broad support by Parties for a science-based indicative goal for the reduction of global emissions of greenhouse gases to the middle of the century," Michael Zammit Cutajar, chair of a U.N. group examining new ideas, wrote in a 30-page summary.

"There is a lack of convergence on the issue of the contribution by different groups of countries to the achievement of the long-term goal and pathways to it," it says.

PROPOSALS Parties have submitted a wide range of "aspirational" or "indicative" goals for cuts by the year 2050. The Group of Eight leading industrial nations, for instance, has a "vision" of halving world emissions by 2050.

Goals submitted to the U.N. talks include:

-- A limit to global average temperature increase, such as 1.5 or 2.0 degrees Celsius (2.7-3.6 Fahrenheit) above levels before the Industrial Revolution.

-- Stabilizing greenhouse gas concentrations in the atmosphere, at around 450 parts per million carbon dioxide equivalent (CO2 eq), or 350 ppm CO2 eq.

-- Reductions in world greenhouse gas emissions, such as a reduction of 50 per cent of 1990 levels, or without specifying the base year. Another proposal is a reduction of between 75 and 85 per cent (including ranges within these figures) of 1990 levels.

-- Setting a global average for greenhouse gas emissions per capita of about 2 metric tons of carbon dioxide.

PROPOSALS FOR DEVELOPED NATIONS

-- By 2050, a reduction in greenhouse gas emissions of 85 per cent, of 95 per cent, within the range of 75-95 per cent and within the range of 80-95 per cent of 1990 levels.

-- By 2020, reduction in their greenhouse gas emissions of 25-40 per cent of 1990 levels.

-- Not setting any quantitative ranges for emission cuts.

PROPOSALS FOR DEVELOPING NATIONS

-- By 2050, reduction in greenhouse gas emissions of 25 per cent of 2000 levels.

-- "Substantial deviation" in emissions by 2020 from the baseline. Some Parties have proposed a range for this deviation of 15-30 per cent, at least for a group of most economically advanced developing countries.

-- Not setting any quantitative ranges for emission reductions, but defining emissions paths to ensure economic growth and social and welfare benefits.

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(Editing by Ralph Boulton,