Climate change has reached everyone on planet Earth, and some of its consequences may be irreversible, concluded the report published on Monday (9) by the IPCC (Intergovernmental Panel on Climate Change), linked to the UN (United Nations).
In Brazil, if the Earth warms from 2ºC to 4ºC, all scenarios described in the document predict a drier country, with 10% to 20% less rain in the coming years, mainly in the central region of the country and in the east of the Amazon.
Scientists predict less rainfall in central Brazil and eastern Amazon in coming years (credit: Piyaset/Shutterstock)
“It is indisputable that human activities are causing climate change, making extreme weather events, including heat waves, heavy rains and droughts, more frequent and severe,” said physicist Paulo Artaxo during an online seminar promoted by FAPESP (Research Support Foundation of the State of São Paulo) this Monday afternoon (9).
Artaxo is one of the authors of the IPCC paper and one of the most prominent climate scientists in the world.
“[O que está acontecendo] it is not a matter of natural climate variability, which always exists, but it is a drastic change that is unprecedented in the last 2,000 years”, said the scientist. “There is no other known mechanism that can explain a warming in less than 100 years caused by any Earth’s orbital forcing around the sun. The science is very clear on this point.”
“Temperature is just one of the elements in this context. Warming causes changes in the hydrological cycle, which has an impact on the frequency and intensity of rains,” said Lincoln Alves, a researcher at the National Institute for Space Research (INPE) who is also one of the authors of the IPCC report.
“At every half degree of warming, we have noticeable increases in rainfall in some places, as well as drought in other places,” said the scientist.
Flooding in a street in Rio de Janeiro, in 2018 (credits: Celso Pupo/Shutterstock)
The seminar, broadcast on Agência FAPESP’s YouTube channel, was also attended by Thelma Krug, a scientist at INPE and vice-president of the IPCC.
“Some extreme weather events would not have happened without human action,” Krug said. “This was always pending in previous reports, and the current document is very clear when it links the issue of temperature with human action”, he added.
“If global emissions of greenhouse gases continue at current levels in the coming decades, we would reach 2°C warming by the middle of this century,” said the scientist. “This sends a message to policy makers that I believe can bring a new scenario or a new concern. We expect a corresponding reaction.”
The IPCC compiles the results of thousands of climate surveys carried out in recent years. For the most recent report, more than 14,000 studies were reviewed. The document is available for reading (in English) and all scientific references used in it are listed for consultation.
Altogether, more than 200 scientists from 66 countries wrote the document—hundreds more researchers reviewed the report.
The report published on Monday (09) should be followed by another two in 2022, which will address the impacts of climate change and possible solutions.