For the first time, the world's biggest eight industrialised economies recognised that the rise in average global temperature should be limited to 2°C. According to scientific consensus, this is the absolute upper limit if the world is to escape catastrophic climate change.
The G8 leaders consequently pledged to support a global target to cut emissions by 50% by 2050. Moreover, they supported an ambitious long-term target of 80% or more for industrialised countries.
But the base year for calculating emission reductions was left vague, as the declaration merely stated that the reductions should be "compared to 1990 or more recent years". The wording could herald a battle between nations not unlike the one that took place during the EU's internal negotiations, when the EU 15 largely supported a 1990 reference point and many Eastern states argued for 2005.
"The G8 conclusions are the most progressive on the subject ever," a European Commission official stated. As setting a mid-term target was not on the agenda of the meeting, all expectations were met, apart from agreement on the base year, she said.
But environmentalists were far less convinced, arguing that the 2°C threshold would be exceeded without a collective agreement on a 2020 target.
"World leaders have come down to earth. We welcome them back here, but why have they failed to tell us how they want to achieve what they promise?," said Kim Carstensen, leader of the WWF's Global Climate Initiative.
According to the Intergovernmental Panel on Climate Change (IPCC), a prestigious scientific body, industrialised countries will need to cut their emissions by 25-40% by 2020 in order to avoid disastrous climate change.
Pledge to invest in green energy
The G8 leaders got a more positive evaluation for their focus on energy efficiency and green energies as a strategy for moving out of the depression.
"The G8 has recognised the need for greater investment in energy to expand employment and ensure resumption in economic growth, while also achieving reduced emissions of greenhouse gases and more secure energy supplies," said Nobuo Tanaka, executive director of the International Energy Agency (IEA).
"At a time of widespread uncertainty, governments can and must lead the way through increased energy diversification and most importantly, improved energy efficiency, both of which can reduce oil market tightness and volatility," Tanaka said.
The G8 countries drew attention to the green dimension of their fiscal stimulus packages, including energy efficiency measures and support for renewable energy technologies and clean coal, and pledged continuous commitment.
They stressed that subsidies encouraging carbon-intensive energy consumption should be slashed, while simultaneously putting in place regulatory frameworks to support a transition to a low-carbon economy.
The meeting also acknowledged carbon markets as a central contributor to reducing emissions. G8 leaders said emissions trading is one of the most cost-effective means of boosting investment in energy efficiency, renewable energy and clean technologies, complemented by other incentives such as fees and emission taxes.
The EU's proposal for a sectoral crediting mechanism whereby developing countries could gain offset credits by exceeding emissions reduction targets in a particular sector was also reflected in the final summit document. It called for the reform of the Kyoto Protocol's Clean Development Mechanism (CDM), which is based on projects that have come under increasing criticism for failing to achieve their climate targets.
Promise to help emerging economies
After developing countries attending the 17-nation climate change talks refused to commit to specific goals to reduce their output of greenhouse gases, the world's richest economies have pledged to help emerging economies meet the costs associated with reducing their industrial carbon emissions.
In a nod to the growing influence of India and China, US President Barack Obama has asked international finance ministers to put forward ideas for helping to pay for reform in emerging economies. They will report to a meeting of the G20 in Pittsburgh in September.
"Developing nations have real and understandable concerns about the role they will play in these efforts," Obama said.
"They want to make sure that they do not have to sacrifice their aspirations for development and higher living standards. Yet, with most of the growth in projected emissions coming from these countries, their active participation is a prerequisite for a solution."
From G8 to G14 or G20?
Obama's words clearly indicate how the exclusive G8 club of elite economies is increasingly unable to solve problems alone and is forced to share influence with other countries to get things done.
Many of these G8 deliberations have included other groups in recent years. China, India, Brazil, Mexico and South Africa have been attending Group of Eight summits as guests since 2007. While their presence has become a given, the failure to grant them full membership has only widened divisions.
Yesterday's meeting on climate change included all of the above, plus others like Australia, South Korea and Indonesia. And in the autumn, many of these nations, plus others, will get together for the G20.
Some national leaders want to replace the Group of Eight with the Group of 20, which includes such countries as Argentina and Saudi Arabia and collectively represents three quarters of the world's population.
"I think the path will lead to the G20," German Chancellor Angela Merkel told reporters in Berlin on Tuesday.
French President Nicolas Sarkoxy, who last year called the Group of Eight format "obsolete," said that the club needed to expand. But he suggested that 20 members might be too unwieldy and is opting for a G14, he said yesterday in a press conference.