BONN, Germany -- A global climate agreement being negotiated this week in Bonn is supposed to apply to all countries, from large industrialized economies to tiny island nations.
But the major climate polluters are expected to lead the way by setting targets for reducing emissions of climate-warming gases including carbon dioxide, well in advance of the Paris summit where the agreement is supposed to be adopted six months from now.
To date, countries representing about one-third of global emissions have submitted what's known in UN lingo as Intended Nationally Determined Contributions. Early analyses by climate researchers and environmental groups show the combined impact falls short of the sharp cuts in emissions that scientists say are required to keep global warming in check.
Here's a look at what the biggest polluters have offered, each using their own timeframes and accounting methods:
EUROPEAN UNION: Collectively, the 28-nation EU is the world's third-largest source of greenhouse gas emissions. The bloc has pledged to cut its emissions by at least 40 per cent by 2030 compared to 1990. It's already halfway there, having slashed climate pollution by nearly 20 per cent since 1990. Renewables like wind, solar and hydropower make up about 15 per cent of its energy mix and the EU aims to boost that to 27 per cent in 15 years.
UNITED STATES: The biggest climate polluter historically and current No. 2, the U.S. aims to make its 2025 emissions 26-28 per cent lower than they were in 2005. That's equivalent to a 14-17 per cent reduction below 1990 levels, according to Climate Action Tracker, a research group that analyzes countries' targets. In its submission to the UN, the U.S. said it plans to achieve its target with a range of measures, including stricter standards on carbon pollution from power plants and motor vehicles and reducing the use of highly potent greenhouse gases used in refrigeration and air conditioning.
MEXICO: Most developing countries aren't expected to cut their emissions in the next decade because they need fossil fuels -- a key source of energy and emissions -- to grow their economies. But they can slow the increase in emissions by boosting the share of renewables, increasing energy efficiency and other measures. Mexico has pledged for its 2030 emissions to be 25 per cent lower than they would have been without any climate actions. It's willing to raise that target to 40 per cent with financial and technological support from rich countries.
CHINA: The world's most populous country and top climate polluter is expected to submit its climate target to the UN by the end of June. But in a historic joint announcement with the U.S. in November 2014, it gave an indication of what the highlight will be: a pledge to peak its emissions around 2030. Some analysts project China's peak will come sooner. Much will depend on whether the country is able to reduce its dependency on coal for electricity generation. Coal generates the highest emissions of all fossil fuels.
JAPAN: Japan, the world' fifth-largest emitter of greenhouse gases, hasn't officially submitted a target to the UN but announced plans to reduce emissions by 26 per cent from 2013 to 2030. Critics say that's less ambitious than what the U.S. and EU have offered. According to Climate Action Tracker, it corresponds to an 18 per cent reduction below 1990 levels. The government wants to restart nuclear reactors that met upgraded safety standards following the 2011 disaster in Fukushima. Meanwhile, fossil fuels remain the preferred option, with more than 40 coal-fired power plants planned or under construction. Japan's plans call for fossil fuels to account for just over half of total power generation in 2030, with 24 per cent from renewable energy and 22 per cent from nuclear power.
RUSSIA: Moscow has pledged to reduce greenhouse gas pollution by 25 to 30 per cent by 2030, compared to 1990 levels. Russian emissions fell sharply with the collapse of the Soviet economy but have started climbing again. It's unclear how Russia plans to account for the effect on emissions of its vast forestry sector -- forests absorb carbon from the atmosphere. Climate Action Tracker estimates that if forests are part of the Russian target, it would mean industrial emissions would only need to decrease by 6 to 11 per cent compared to 1990.
CANADA: After withdrawing in 2007 from the Kyoto Protocol, the emissions treaty that the Paris agreement is meant to succeed, Canada has been widely viewed as a laggard in the UN climate talks. Ottawa has pledged to cut emissions by 30 per cent below 2005 levels in 2030. Observers of the climate talks have dismissed that target as too weak, but also raised questions about whether it can be achieved. There are doubts over whether Canada will meet an earlier, voluntary target to reduce its emissions by 17 per cent in 2020, mainly because of growing emissions from tar sands projects.
OTHERS: India, Brazil and Australia are among the largest emitters that haven't yet presented their targets. UN officials hope that most countries will have done so by October so that they can be added up and their aggregate effect evaluated before the climate summit in Paris.
