Universidade Federal de Santa Catarina

In a report released this Thursday, 4 November, at the UN Conference on Climate Change (COP26), a group of scientists highlighted some of the most important recent discoveries related to climate change. The document 10 New Insights in Climate Science is a compilation of an article published in October on the University of Cambridge website, produced by 62 researchers from 22 countries and five continents. The professor at the Department of Physics at the Universidade Federal de Santa Catarina (UFSC) Marina Hirota is one of the authors.

Aimed at decision makers, the material summarizes the advancement of scientific knowledge, with data from studies published in the last year, on some of the most urgent topics and has the intention of raising awareness about the actions necessary to preserve a safe and habitable planet. In presenting the report, the executive secretary of the United Nations Framework Convention on Climate Change (UNFCCC), Patricia Espinosa, highlighted that the topics cover distinct but interrelated issues, such as the increase in mega-fires around the world and new justifications related to the cost-benefits of rapid climate action. Each item is accompanied of political recommendations in many different scales of action – from global do local.

“Although we are quickly running out of time to slow climate change, this report shows that stabilizing in 1,5ºC is still possible, but only if immediate and drastic global measures are taken”, affirmed Wendy Broadgate, director of the Future Earth Global Hub, in Sweden. “Global leaders of the COP26 must define aggressive goals of emission reduction – nothing less than 50% less greenhouse effect gas until 2030 and liquid goals of zero emission until 2040, is enough”, adds Broadgate.

The report also warns that the rapid growth in methane and nitrous oxide emissions has set us on the path to a 2.7°C warming. As Johan Rockström, director of the Potsdam Institute for Climate Impact Research and co-chair of the Earth League, warns, the science is clear: exceeding 1.5°C of global warming poses major challenges for societies around the world and increases the risks of crossing points of no return in critical locations for regulating the climate system – such as the Amazon, for example.

It is in this aspect that Marina Hirota’s major contribution to the report lies. The teacher worked with the so-called tipping elements, a term without translation into Portuguese, but which refers to elements of the planet that have a non-linear behavior and that are subject to abrupt and catastrophic changes after crossing certain thresholds (which may be related to a high temperature, a change in the rainfall regime or the level of degradation of an ecosystem, for example). The Amazon, the Greenland ice sheet and the circulation of the Atlantic Ocean are examples of tipping elements. It is noteworthy that they are all interconnected. Changes in one of them cause a domino effect, with serious effects on several other systems on the planet.

With Amazon, the focus of Marina’s studies, the situation is especially worrying. “There are parts of the Amazon that are already showing a new configuration behavior, on several fronts. For example, southeastern Amazonia is already behaving as a carbon source, rather than a sinkhole. This is a very recent study. This [occurs] independently of fire, which is what most emits, what most transforms the forest into a source [of carbon]. So, regardless of the fire, we already observe that the forest is emitting more carbon than absorbing it”, comments the professor. There are even regions that have already become a type of impoverished savannah. Also noteworthy is the fact that 17% of the original Amazon area has been deforested and that 18% is degraded – meaning that there may even be trees standing in these regions, but disturbances such as fires and illegal logging have led to impoverishment of the forest, with loss of biodiversity and reduction of ecological functions, for example.

What does that mean? That we are very close to what was hypothesized as a limit of 20 to 25% of change in vegetation cover in the Amazon”, says Marina. This is believed to be the threshold of a point of no return, from which the forest could no longer recover. “Although this has not been fully proven, and it isn’t, we could call it, which I think is not worth it. So, it’s about taking an attitude of really having a deforestation moratorium, of reducing deforestation to zero in a brief time, increasing inspections, and all that stuff, because that can really cause a collapse of the system”, she emphasizes.

The researcher also highlights other aspects of the report that have more direct relations with Brazil, such as the great fires (such as those that affected the Amazon and the Pantanal recently), which should become more and more frequent, and the reflection on the preservation of coastal ecosystems – including reefs and other animal populations and coastal vegetation, such as restingas and mangroves.
The study shows that, given that human and ecosystem health are closely linked, profound changes in energy and consumption patterns are needed, which must consider justice and equity, including support for vulnerable populations. The good news is that new research shows that the costs of mitigating climate change are far outweighed by the immediate benefits to people and the planet. This includes the restoration of natural ecosystems – which also represent high economic value – and improvements to human health and well-being. The transition to renewable energy, for example, could dramatically reduce the 6.67 million deaths caused by air pollution annually in the world.

The study also recognizes the role of individual actions (what each of us can do to lower our ecological footprint) and the need to adopt nature-based solutions. “This is also very, very important for Brazil, in terms of well-done restoration. Not only planting trees, but restoring ecosystems, not only the Amazon, but also the Cerrado, the Caatinga, the Atlantic Forest, the Pantanal, the Pampas, all these biomes. And works that involve science, civil society, private initiative, local people toward restoring these ecosystems effectively, not just planting trees everywhere making no sense of it. It makes little sense for you to plant trees in the Pantanal, a flooded place, for example. That people get more and more involved in this, in initiatives that have this as their goals. And it doesn’t matter the scale on which it is done”, emphasizes Marina. She cites, as an example of local action, the project by professor of the Department of Zoology and Ecology at UFSC Michele de Sá Dechoum, which involves the removal of invasive pine trees in the Dunas da Lagoa da Conceição Municipal Natural Park, since exotic trees compromise the biodiversity of the site.
“Our knowledge of the climate system has skyrocketed in recent years, but policymaking has not yet achieved these critical advances,” says Detlef Stammer, professor at the University of Hamburg and chair of the scientific committee of the World Climate Research Programme. “The findings of this report are a strong call to decision makers to address the urgency of the state of our climate and help put us back on a path to a sustainable future,” adds Stammer.

Get to know the ten reflections:

1. Stabilization of warming at 1.5°C is still possible, but immediate and drastic global action is needed.
2. The rapid growth of methane and nitrous oxide emissions has put us on the path to a 2.7°C warming.
3. Mega-fires – climate change forces extremes of fire to reach new dimensions with extreme impacts.
4. Tipping elements are subject to high impact risks.
5. Global climate action must achieve equity.
6. Supporting individual behavior change is a crucial but often overlooked opportunity for climate action
7. Policy challenges impede the effectiveness of carbon pricing.
8. Nature-based solutions are critical for the road to Paris – but attention to detail is essential.
9. Building resilience of marine ecosystems is achievable through climate-adapted conservation and management and global stewardship.
10. The costs of climate change mitigation can be justified by multiple immediate health benefits for people and nature.

More information at 10insightsclimate.science.

Camila Raposo/Journalist from Agecom/UFSC, with information from Future Earth, The Earth League and World Climate Research Program (WCRP)

Translated by SINTER/UFSC

Read the original article here