The current discourse on climate change can have a reverse effect when it comes to the production of Risk in occupation processes. The topography of Rio de Janeiro, steep, rich in hills and slopes, with its flood-prone lowlands, presents a complex urban site that has been constantly marked by landslides and flooding. Building a city, dwelling well, and living well require, under these conditions, consistent work in attention, planning, and assertive public policies. The tropical climate affecting Rio de Janeiro is mainly associated with the dynamics of cold front incursions, at this latitude, close to the Tropic of Capricorn, where cold and warm air masses interact in a seasonal rainfall regime. This condition has been established for just over 10,000 years, marking the end of the last glaciation. The famous Ice Age, which characterizes the last geological epoch (the Pleistocene), came to an end, and a significant global warming process led to the tropicalization of the climate in our region. These glaciation cycles were described by the Serbian Milankovitch, who studied changes in Earth's orbital trajectory around the Sun, understanding that they can cause cyclical changes in the amount of solar radiation reaching the planet. These pulses of energy end up shaping the rhythms of Earth's climate over time, creating Ice Ages, alternating with warmer interglacial periods. The tropicalization that marks the beginning of our current epoch, called the Holocene, caused the expansion of tropical forests, which reduced the savanna areas (Cerrado and Caatinga) adapted to the dry, cold climate. The Amazon Rainforest and the Atlantic Forest ecosystems occupy the areas where humidity concentrates, and used to cover much of the equatorial belt and the Atlantic coast, respectively. With this climate change, tropical rains became part of the new normal climate curve, which would considerably increase rainfall rates in these regions, including Rio de Janeiro. The rainfall regime, increased in volume, now responds to the seasonality of the year's seasons, generated by an orbit closer to solar radiation, and therefore globally warmer. The alternation between winter and summer in the southern hemisphere results from the Earth's revolution around the sun, due to a tilted rotation axis. Therefore, although rainfall rates remain almost constant throughout the year, the tropical summer is marked by concentrated rainfall, while winter is marked by greater scarcity. Thus, for at least the last 10,000 years, summer rains have occurred here. These rains, also in response to astronomical processes of proximity to and distance from the sun, or greater or lesser solar radiation, among other factors, occur in cycles of 5 years, 10 years, 30 years, or more, with extreme rainfall. So-called extreme events, which concentrate a high rainfall index in a short time, known as Tropical Storms, Tropical Tempests, or Downpours, are common and are part of the normal curve of our climate. Therefore, it is expected and known that extreme events will occur from time to time; they are extreme, but not extraordinary -- on the contrary, they are ordinary and have been happening for a long time.
Recent studies on human influence on global climate change deal with another subject. They point out, according to recent studies, that the concentration of heat-retaining gases in the atmosphere, especially those generated by the emission from the burning of fossil fuels, causes the temperature of the Earth's atmosphere to rise, disrupting the cycles established since the Holocene.
The so-called Milankovitch cycles have already been understood by science for more than a century, and precisely for this reason, when researchers point out that the climate changes we experience today originate from human actions, it is because the hypothesis that this might be merely a natural variation of the system has already been considered and ruled out. According to these authors, what we are experiencing now is happening at a much faster pace than the planet's natural rhythms.
So what we can call erroneous narratives are those that take advantage of the discourse on Anthropogenic Climate Change to blame processes that occur not because of a change in the pattern of ordinary rainfall, even if extreme, but because of a terrible model of urbanization. Regardless of the Climate Change caused by humanity in recent centuries, even if it hadn't occurred, Rio de Janeiro's urban problems would still have worsened. Normal rainfall, sometimes of small magnitude, causes floods and landslides in areas where occupation was poorly carried out. Even if there were no changes in the climate, disasters happen because of the city's poor management. These disasters are not natural or merely the consequence of climate phenomena, but of urban growth based on inadequate occupation of the land, especially in risk areas, such as hillsides and lowlands. The true solution to the problem requires an ongoing commitment to reorganizing urban space, one that does not understand the city as a commodity, but that incorporates occupation planning with the conservation of the environment's own dynamics where it takes place. Rio de Janeiro's future will depend on its capacity to integrate urban growth, creating safe spaces for its inhabitants and quality of life and full existence.
Image description: The image presents a text written in Brazilian Portuguese. It is arranged horizontally, with black letters on a light background. The text mentions "Strange August: in one hour it rained more than the monthly average." There are no additional graphic elements or specific colors other than black and white.New Year's Eve in Copacabana
