Five things we learned from the IPCC report

BBC Environmental Correspondent Matt McGrath presents five key findings from one of the most important reports on rising temperatures published by the Intergovernmental Panel on Climate Change. Their study, on the impacts and possible methods to prevent temperatures from warming more than 1.5 ° C, has just been launched in South Korea.

It's "seriously alarming" but surprisingly full of hope

There is no doubt that this 33-page, science-intensive summary is the most significant warning about the impact of climate change in 20 years.

"It's very alarming," Amjad Abdulla, one of the leading authors of one of the Maldivian chapters, told BBC News.

"The small islands will be first, but no one can escape, it's very clear."

But if warnings about the dangers of letting temperatures exceed 1.5 ° C are terrible, the report indicates, surprisingly perhaps, that the world can stay below the limit.

"We face a daunting challenge, but it's not impossible to limit warming to 1.5 ° C," said Dr. Natalie Mahowald, author of the IPCC.

"I would not be too optimistic because it will require huge changes, but if we do not, it will also require huge changes."

Every little contribution

The report goes to great lengths to highlight the differences between a temperature of up to 2 degrees Celsius above pre-industrial times and a temperature closer to 1.5.

Half a degree does not seem like much, but that it's coral reef, crop, flood or species survival, everyone is much better in a world that stays below 1.5 ° C.

"Every additional warming makes the difference," said IPCC Dr Hans-Otto Pörtner.

"From here 2100, the average global sea level rise will be about 10 cm lower for a 1.5 degree warming compared to 2 ° C. That could mean up to 39 to 10 million people less exposed to the risks of rising seas.

Similarly, with respect to heat waves, in a world where warming reaches 1.5 ° C, about 14% of the population is exposed to a heat wave every five years. This increases to 37% of the population at 2C.

This is not the option A, B or C; it's the option A + B + C

The headlines on reducing emissions by 45% by 2030 and almost all of our electricity produced from renewable energies by the middle of the century are all fine, but one of the key points of this report is that limiting climate change to 1.5 ° C is not just a drop. reduce emissions, change the way of life or plant trees – that's all, and some, acting together at the same time.

"All options must be exercised to reach 1.5 ° C," said Prof. Jim Skea, Co-Chair of the IPCC.

"We can make choices about the options and exchange a little bit between them, but the idea of ​​not omitting anything is not possible."

We do not need to reinvent the wheel to limit warming

We believe a lot in technology to solve many of our environmental problems, especially climate change.

This report indicates that the world does not need magic machines to fight climate change – we already have all the technologies we need.

The report states that carbon will have to be extracted from the air by machinery and stored underground, and that these devices already exist.

Billions of trees will have to be planted – and people may have to make difficult choices between using land for food or using it for energy crops.

But really crazy ideas, such as blocking the sun or adding iron to the oceans, have been rejected by this IPCC report.

That's (in part) to you!

This new IPCC study differs from previous approaches in that it clearly establishes a link between lifestyles and warming.

The report's authors say that rapid change must occur in four key sectors of society:

• energy production
• land use
• cities
• industry

Many people might think that they have little personal involvement in these areas – but the IPCC authors say this is not the case.

"It's not remote science, but rather knowing where we live and work," said Dr. Debra Roberts.

"The energy we buy requires that we put pressure on the policy makers so that they offer me options so that I can use renewable energy in my everyday life."

Reducing energy demand by consuming less is an extremely efficient step.

In the same way, being aware of what you are eating, where it comes from, thinking about how you are traveling, becoming more interested in all of these things can have an impact on energy consumption.

This increased awareness and the changes it might inspire could even be beneficial to you.

"Frankly, the more we are willing to change patterns of behavior to reduce greenhouse gas emissions, the less we will need to rely later on more difficult options that we do not yet understand as the elimination of carbon dioxide, "said Professor Jim Skea.

"There are a lot of reasons other than climate change to change diets, and if we changed to reflect health recommendations, we would all live longer, drive a lot longer and live better, and reduce emissions. greenhouse gas."