IPCC sets the tone for new climate ambition ahead of COP24

NEW DELHI: Setting the tone for new climate ambition, the Inter-governmental Panel on Climate Change (IPCC) - a UN body which evaluates climate change science - on Monday said the global average temperature was likely to increase by 1.5 degree Celsius between 2030 and 2052 from its pre-industrial levels if it continued to increase at the current rate, leading the world to face far more disastrous consequences of global warming than what was being faced now at 1 degree Celsius rise.


It said, “Climate-related risks for natural and human systems are higher for global warming of 1.5 degree C than at present, but lower than 2 degree C. These risks depend on the magnitude and rate of warming, geographic location, level of development and vulnerability, and on the choices and implementation of adaptation and mitigation options”.


Besides noting the consequences, report also enlists ways to slow down the warming process and limit the rise to 1.5 degree Celsius by 2100 - well below the 2 degree Celsius rise which is the intended goal of the Paris Agreement on climate change.

The IPCC came out with its findings and analysis of available options to limit global average temperature rise in its special report on ‘Global Warming of 1.5 degree Celsius’, released at Incheon in South Korea on Monday.

The report examines pathways available to limit warming to 1.5ºC, what it would take to achieve them and what the consequences could be.

It will, therefore, be a key scientific input into the Katowice Climate Change Conference (COP24) in Poland in December, when governments review the Paris Agreement to tackle climate change.

The Paris Agreement, adopted by 195 nations at the 21st Conference of the Parties COP21) to the UNFCCC in December 2015, included the aim of strengthening the global response to the threat of climate change by “holding the increase in the global average temperature to well below 2 degree C above pre-industrial levels and pursuing efforts to limit the temperature increase to 1.5 degree Celsius above pre -industrial levels.” The reference period 1850-1900 is used to approximate pre-industrial levels.

As part of the decision to adopt the Paris Agreement, the IPCC was invited to produce, in 2018, a Special Report on global warming of 1.5 degree C above pre-industrial levels and related global greenhouse gas emission pathways.

The IPCC’s special report highlights a number of climate change impacts that could be avoided by limiting global warming to 1.5ºC compared to 2ºC, or more. For instance, by 2100, global sea level rise would be 10 cm lower with global warming of 1.5°C compared with 2°C.

Similarly, the likelihood of an Arctic Ocean free of sea ice in summer would be once per century with global warming of 1.5°C, compared with at least once per decade with 2°C. Coral reefs would decline by 70-90% with global warming of 1.5°C, whereas virtually all (> 99 percent) would be lost with 2ºC.

The report, however, finds that limiting global warming to 1.5 degree C would require “rapid and far-reaching” transitions in land, energy, industry, buildings, transport, and cities.

It said the global net human-caused emissions of carbon dioxide (CO2) would need to fall by about 45% from 2010 levels by 2030, reaching ‘net zero’ around 2050. This means that any remaining emissions would need to be balanced by removing CO2 from the air.

“Stabilisation of average global temperature rise to 1.5 degree C has clear benefits as compared to 2 degree C rise. Science says it is not impossible to limit the warming to 1.5 degree C. We should, therefore, give it a try. The countries need to scale up their ambitions,” said Joyashree Roy, one of the five Indian authors of the IPCC report.

Citing examples of extreme weather events in India, another India author, Aromar Revi, said, “We had already seen extreme weather events in Kedarnath, Chennai and Kerala. Other parts of the globe faced similar events. Options to limit global warming to 1.5 degree Celsius exist. We need to act on it. Otherwise, the cost to deal with the problem will be much higher later”.

Allowing the global temperature to temporarily exceed or ‘overshoot’ 1.5 degree C would mean a greater reliance on techniques that remove CO2 from the air to return global temperature to below 1.5 degree C by 2100. The effectiveness of such techniques are, however, unproven at large scale and some may carry significant risks for sustainable development, the report notes.

“Limiting global warming to 1.5 degree C compared with 2 degree C would reduce challenging impacts on ecosystems, human health and well-being, making it easier to achieve the United Nations Sustainable Development Goals,” said Priyardarshi Shukla, Co-Chair of IPCC Working Group III.

Ninety-one authors and review editors from 40 countries prepared the IPCC report.

“The IPCC report is a wake-up call for slumbering world leaders. We must reduce emissions as quickly as possible to keep 1.5 degrees of warming within reach. The difference in impacts between 1.5 and 2 degrees of warming is large, and potentially game changing. And, the devastation that would come with today’s 3-4 degree Celsius trajectory would be vastly greater. Each tenth of a degree matters – and tragically it’s the poor who will be most affected,” said Andrew Steer, President & CEO of the World Resources Institute (WRI).

According to the report, Arctic ecosystems, small island developing countries and least developed countries are among the regions which are at “disproportionately higher risk” of adverse consequences of global warming of 1.5 degree C.