Global warming is now considered one of the greatest challenges faced by humanity. Marco Aurélio Vasconcelos de Freitas, from the Instituto Nacional de Pesquisas Espaciais - INPE / MCTI - (the National Institute for Space Research, used charts and forecasts at the Debate Arena to show how global warming is likely to impact the Earth in the next 100 years. He also pointed out ways to reduce carbon emissions, especially by using renewable energy.

"Let us recall Rio 92. Up to 1994, global warming was still being questioned, not everyone thought it was a real phenomenon,” said Freitas. "The agreements made under the Kyoto Protocol did not scratch the surface of global warming, and managed a reduction of 0.5% at most in carbon emissions," he said.

The researcher explained that even today it is difficult to separate urban heating, caused by heat islands, from global warming, caused mainly by increased emissions of greenhouse gases, which leads to a fluctuation in the measurements at various institutes. He also revealed that one factor that distorts opinion is the observance of colder winters in the northern hemisphere, a factor that at first seems to contradict global warming, but which is actually a result of the melting of the poles.

On the issue of the Brazilian energy grid, he stressed the role of hydroelectricity, wind energy and biomass as alternatives to burning fossil fuels.

Freitas used a chart to show how renewable sources have become more efficient, popular and inexpensive over time. "In the 1970s, alcohol was known as 'the vinasse industry'," he said, referring to one of the harmful byproducts of alcohol production from sugarcane. "Currently, the plants not only produce alcohol but are self-sufficient in electricity, and even sell power to the Brazilian energy grid," he said.

The Science and Technology for Sustainable Development Exhibitions, by the Ministry of Science, Technology and Innovation (MCTI), will continue until Friday (June 22), from 9 am to 7 pm, at Warehouse 4, on Pier Mauá.

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Text: Gerhard Brêda – Press Office, MCTI