IPCC: Climatologists consider report "change of life"

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Jonas Gratzer

This will probably be the most critical and controversial report on climate change in recent years.

Renowned scientists are meeting this week in South Korea to see if it is possible to prevent global temperatures from rising above 1.5 ° C during this century.

The world has already passed a degree of warming because carbon emissions have skyrocketed since the 1850s.

Many low-lying countries claim that they may disappear under the sea if the 1.5 ° C limit is exceeded.

After a week of deliberations in the city of Incheon, the new report by the researchers will probably indicate that to stay below this limit, urgent and dramatic measures will have to be taken by governments and citizens.

A scientist told BBC News that our lives would never be the same again if the world changed course to stay below 1.5 ° C.

The new study is being developed by the Intergovernmental Panel on Climate Change (IPCC), which provides governments with a clear scientific vision of the causes, impacts and solutions to climate change. rising temperatures.

When signing the Paris Climate Agreement in December 2015, many delegates were delighted and surprised to learn that countries had agreed that the long-term goal of the pact should be maintain global temperatures "well below two degrees above pre-industrial levels and continue efforts to further limit the temperature rise to 1.5 ° C".

To examine the challenges and impacts of maintaining temperatures below the 1.5 ° C limit, the UN has asked the IPCC to produce a special report, which the scientific body has provided in record time.

This week in Incheon, scientists and government delegates will review the brief 15-page summary for policymakers, which is the cornerstone of the underlying scientific reports.

This will be done word for word, to ensure that everyone – scientists and governments – agree on the text.

Why is this report important?

The report will guide governments in their decision to develop their economy in the face of rising temperatures over the next few decades.

"The decisions we are making now about whether we leave 1.5 or 2 degrees or more will profoundly change the world," BBC News, Dr. Heleen de Coninck, one of the main coordinating authors of the report, told BBC News. .

"But our lives, if we keep it below 1.5 ° C with the expected increase in population and economic growth, will also look different."

"People's lives will never be the same, anyway, but we can influence the future with which we find ourselves."

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SOPA Images

At present, the world has surpassed a degree of warming above global temperatures by about 1850, before widespread industrialization.

The drafts of the new report suggest that global warming is on track to exceed the 1.5 ° C mark by 2040.

This is very bad news for low-lying island states and some of the world's least developed countries, who fear 1.5 C will cause sea level rise and threaten their survival.

How does the IPCC work?

Slowly and carefully enough.

The IPCC has been in existence for 30 years and produces detailed assessments of the state of the climate every six or seven years.

This special report has been in preparation for almost three years.

The authors are all scientists appointed by governments and international institutions.

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Getty Images

In this case, there are 86 leading authors from 39 countries, of which 39% are women.

These unpaid researchers reviewed the available scientific literature on the feasibility, impacts and costs of conservation below 1.5 ° C.

They then prepared draft versions of their report, after reviewing some 6,000 references.

These draft reports have been sent to other experts and governments for consideration. In total, this report received over 40,000 review comments.

Because so many people are involved and all these comments have been taken into account, the IPCC has a reputation for being rather conservative, producing reports that have a very broad consensus.

The people involved declare that the wide range of publications and the large number of authors involved constitute an essential force of the body.

"We do not base our reports on one article that has an extreme conclusion, which contrasts with the available literature," said Dr. Carolina Vera, IPCC Bureau member.

"The collective vision of the available literature is the strongest contribution we can make to governments."

So why is this report controversial?

If you add up all the promises of carbon reduction made by the signatory countries of the Paris climate agreement, the world would warm up by more than 3 ° C by the end of the century.

For some scientists, there is not enough time to take action that would keep the world within the desired limits.

"If you seriously examine the feasibility, you will find that it will be very difficult to reach the 1.5C," said Professor Arthur Petersen, a former IPCC member from University College London.

"I am relatively skeptical about the possibility of reaching 1.5 ° C, even if exceeded, scientists can imagine that it is feasible, but it is a pipeline."

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FADEL SENNA

In addition to science, there is also politics.

For some countries, especially those that are the main exporters of fossil fuels, it is difficult to limit carbon emissions faster than today.

"The big question in this report is: how can we still achieve this 1.5C goal? What does it take?" Said Kaisa Kosonen of Greenpeace.

"There are those for whom 1.5C is a matter of life and death and they want the message to be clear.Others might want to suggest that there is no scientific certainty and the messages, for example on the rapid elimination of fossil fuels, should not be so simple. "

What will the report probably recommend?

The challenge of maintaining temperatures below 1.5 is considerable. But, if accepted by governments, the report will probably indicate that this can be done if the world is ready to take very difficult steps.

These will likely involve intensified reductions in CO2 emissions, a rapid shift towards renewable energies and, most likely, the deployment of technologies to suck up greenhouse gases in the air.

This last option is considered very controversial.

The report will also likely indicate that lifestyle and diet choices can make a significant difference – but there is no simple or inexpensive solution.

"There is no easy answer, it's a much more complicated answer," said Professor Jim Skea, who co-chairs one of the IPCC working groups.

"It has physical elements, social elements, and political elements, and the report, as it's presented, allows us to address these issues, but I do not think that's what governments are saying to us. asked. "

Who is in charge – scientists or governments?

There has been a lot of speculation that scientists are forced to soften the content of the report, or to "pull their fist", on some of the key findings.

What has happened is that there have been notable changes between the different draft versions of the executive summary, which will be officially released on Monday, October 8th.

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David McNew

This has led some critics to conclude that important aspects are minimized to meet the interests of countries with significant fossil fuel industries, such as the United States, Saudi Arabia, and Australia.

But IPCC members say they will not let their findings dwindle over the next few days when the summary is gone line by line.

"What is really important for the work of the IPCC is the respect for the integrity and scientific rigor of the authors, which is at the heart of the work of the teams of authors." said Valérie Masson-Delmotte, co-chair of the body.

"If you can imagine governments holding the hands of scientists, it means you do not know how science works!"

Will sparks fly during this meeting?

Probably yes!

IPCC sessions are closed to the public to allow governments and scientists to freely express themselves. Governments are often trying to change the text – scientists are there to make sure the changes are consistent with the research.

"I've never been to an approval session that did not work well after hours, it's kind of a working practice of the IPCC now," said Professor Skea. .

"Absolutely it will be a solid session and we are well prepared for that."

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