Officially the Intergovernmental Panel on Climate Change (IPCC), it says it would take an unprecedented level of action from countries over the next few decades to reduce their greenhouse gas emissions. An overhauling of energy systems is needed; tinkering and tweaking the economy will not.

Termed "Mitigation of climate change", this is the third in an IPCC series called Assessment Report 5. Important for the formal UN climate negotiations, as this sets scientific targets that countries must achieve to have a fair chance of keeping the rise in average annual global temperature below two degrees Celsius.

The pledges by countries to reduce emissions so far are substantially short of the effort required, the panel has said. Countries have to come up with an emission reduction target and a method to apportion this across countries by the end of 2015, when a new global compact under the existing UN climate convention is to be signed.

The UN climate negotiations go by the scientific data the IPCC authenticates. So, its latest report was keenly awaited and as keenly fought over during the finalisation. All such reports are prepared by a large panel of scientists but the critical concise version - the Summary for Policy Makers - is negotiated with representatives of various governments, along with the scientists. This becomes the basis for negotiations on any decision regarding action to fight climate change.

This time, the negotiations went to the wire, with developing countries crying foul on the manner in which the assessment had created a new classification of countries. Under the UN climate change treaty, countries have so far been divided into only developed and developing, with the onus of reducing of emissions higher on the former, as they have historically emitted the most.

The science panel report in its draft form, kept secret till negotiations, which Business Standard accessed had classified countries on the basis of income levels, pushing emerging economies into a new category. This favoured developed countries that are keen to get China and India, for instance, to bear a greater burden in reducing emissions for their current and potential future levels. The negotiations ensured the classification was dropped from the Summary for Policy Makers, though it's been retained in the voluminous main report, politically less significant.

________________________________________

SOME KEY POINTS FROM THE UN CLIMATE PANEL

• Almost 80% of the emissions come from industrial processes

• Emissions rose continuously between 1970-2010, with the rate of increasing growing over recent decades

• At current levels of emissions temperatures could rise by 3.7-4.8 degree Celsius on average by 2100. Anything more than two degrees is considered dangerous for the planet

• Emission cuts of 40-70% required from 2010 levels by 2050. Countries have committed to do a fraction of it so far

• Space for sustainable development of poorer countries and equity in sharing the burden of reducing emissions is a must