IPCC Report: "The Next Few Years Are Probably The Most Important In Our History"

INCHEON, South Korea

On October 6, the Intergovernmental Panel on Climate Change (IPCC) issued its “Special Report on Global Warming of 1.5 degrees C”. The report to assess the differences between allowing temperatures to rise towards 2 degrees C above pre-industrial times or keeping them nearer to 1.5 C was commissioned at the Paris Convention in 2015.

At 1.5C the proportion of the global population exposed to water stress could be 50% lower than at 2C, it notes. Food scarcity would be less of a problem and hundreds of millions fewer people, particularly in poor countries, would be at risk of climate-related poverty.

Three working groups assessed different aspects of change: the physical scientific basis of climate change; impacts, adaptation and vulnerability; and climate change mitigation.

"The next few years are probably the most important in our history," Debra Roberts, co-chair of the IPCC Working Group that assessed impacts, adaptation and vulnerability, said in a statement marking the report's release.

While the Paris Convention recommended a report at 2C, heads of heads of small island nations, fearful of rising sea levels, requested an examination of the effects of 1.5 degrees of warming.

Scientists reviewed over 6,000 scientific, technical and socio-economic research works and the impact caused by just one-half degree change in temperature surprised them. The report “is quite a shock, and quite concerning,” said Bill Hare, an author of previous IPCC reports and a physicist with Climate Analytics, a nonprofit organization. “We were not aware of this just a few years ago".

"Scientists are increasingly aware that every half degree of warming matters," Chris Weber, WWF's global climate and energy lead scientist, said in a statement.

"We must have laser focus on delivering on 1.5 degrees and this report provides a pathway to get there. We need to halve greenhouse gas emissions globally by 2030 and cut coal use by two-thirds by the same date."

The report highlights a number of climate change impacts that could be avoided by limiting global warming to 1.5°C compared to 2°C, 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. 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 percent with global warming of 1.5°C, whereas virtually all (> 99 percent) would be lost with 2°C.

At 1.5C the proportion of the global population exposed to water stress could be 50% lower than at 2C, it notes. Food scarcity would be less of a problem and hundreds of millions fewer people, particularly in poor countries, would be at risk of climate-related poverty.

"Every extra bit of warming matters, especially since warming of 1.5°C or higher increases the risk associated with long-lasting or irreversible changes, such as the loss of some ecosystems," said Hans-Otto Pörtner, Co-Chair of IPCC Working Group II. "By 2100, global mean sea level rise will be around 10cm lower for warming of 1.5 degrees compared with 2C. This could mean up to 10 million fewer people exposed to the risks of rising seas."

Successfully limiting climate change to 1.5C is not just down to cutting emissions or making lifestyle changes or planting trees; it is all of that acting in concert contemporaneously. "All options need to be exercised in order to achieve 1.5C," said Prof Jim Skea, an IPCC co-chair of the working group on mitigation. "We can make choices about which options and trade off a bit between them, but the idea you can leave anything out is not possible."

The report's authors say that rapid changes must take place in four key parts of society: energy generation, land use, cities, industry. But the authors also call for urgency on the part of governments.

“We have presented governments with pretty hard choices. We have pointed out the enormous benefits of keeping to 1.5C, and also the unprecedented shift in energy systems and transport that would be needed to achieve that,” according to Jim Skea, a co-chair of the working group on how the emissions that cause climate change can be reduced. “We show it can be done within laws of physics and chemistry. Then the final tick box is political will. We cannot answer that. Only our audience can – and that is the governments that receive it.”

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