Climate Brazil

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Brazil is an immense country, almost entirely located in the intertropical zone of the southern hemisphere. Only the southern part of the country has subtropical characteristics. Nevertheless, the vastness of the territory explains certain climatic variations. In the south of the country, you can experience the frigidity of tropical winters and the changeable weather of the mountains. In Belém, in the state of Pará and in large parts of Amazonia, it is said to be customary to meet before or after the rain. In the Nordeste, drought prevails for part of the year. Climate change is also causing increasing variations in dry spells, alternating with episodes of torrential rain. In short, while it's often hot in Brazil, the notion of an austral winter is not to be overlooked, especially inland to the south and in the highlands of this country-continent.

Brazil, a giant with a tropical climate

A tropical country. More than just the title of a Jorge Ben song that went round the world, Brazil is indeed a tropical country, albeit with variations and nuances. Characteristic of part of the Brazilian territory, this type of climate is characterized by a fairly high average temperature with moderate amplitudes. The austral winter, which runs from June to September, offers cooler temperatures, between 20 and 22°C. The rest of the year, temperatures fluctuate between 23 and 27°C. Rainfall is generally divided into two seasons: a rainy season from September to March and a drier season from October to February. When visiting the Pantanal, the dry season is cooler and more pleasant than the suffocating, mosquito-ridden rainy season. This type of climate has enabled the land to be developed for agricultural purposes. This tropical agriculture, where there is no shortage of water, has turned Brazil into a green giant, a champion of agribusiness. However, this tropicality comes in many shades, from the humidity of the Amazon to the cold of the mountains and the aridity of the Sertão.

The Amazon climate. This is perhaps Brazil's most emblematic region, symbolizing the fight against global warming. The Amazon and the north of the country are characterized by an equatorial climate. Temperatures and rainfall are high all year round, with relatively low amplitudes of temperature and rainfall. Minimum temperatures fluctuate between 21 and 23°C, with maximums between 31 and 34°C. The climate is permanently humid, but rainfall is most abundant between January and May (between 300 and 400 mm per month). This type of climate is favorable to agriculture that requires or tolerates high humidity (e.g. rice growing) and, of course, favors the rapid and permanent growth of a dense forest of large trees. Overall, this difficult climate has not allowed the development of a dense population (even though the Manaus conurbation is approaching 2 million inhabitants). What's more, this "opulence" of nature is only apparent and has long concealed the Achilles' heel of the planet's green lung. Continuous rain washes the soil, stripping it of its mineral salts. The fertility of the Amazon lies in its trees, their biomass and the humus they produce. Unfortunately, irrational deforestation, cattle farming and soya production are irreversibly transforming this extraordinary plant cover into barren lateritic soil.

The Brazil of beaches, a humid tropical or coastal tropical climate. This is the main climate for "tourism", since the major tourist destinations (Rio, Salvador, the north-eastern coast and Fluminense) are marked by its influence and characteristics. Overall, this climate is warm and fairly humid. It is found from the Nordeste coast to the Paraná coast. It is characterized by fairly high and constant humidity (between 1,500 and 2,000 mm), as the coasts are under the influence of the trade winds. Temperatures average close to 25°C. It's a little warmer and more regular in Salvador than in Rio... although in Rio you'll never need a heavy sweater. The rainy season is more marked in the Nordeste than in the Sudeste. In the Nordeste, the rainy season is most marked between April and July, while in the states of Rio and São Paulo, July and August are the driest months. In addition to its importance for tourism, as this climate is pleasant all year round, it has also influenced the original development of Brazil and shaped its "anthropology", especially in the Nordeste. Indeed, this type of climate lent itself perfectly to the development of sugarcane cultivation, which gave rise to the "sugar cycle". The entire coastal fringe of the mata atlântica - the Atlantic rainforest - was cleared to enable the development of sugarcane monoculture, based on slave labor, the fruit of a triangular trade that uprooted over 5 million people from Africa. From the outset, society was organized around the sugar mill(engenho), the master and his house(casa grande) and the slave house(senzala). Although slavery was abolished in 1888, sugarcane is still grown on this coastal fringe, where the mata atlântica, the original forest, has been reduced to a minimum.

Nordeste (Sertão), arid country. The interior of the Nordeste (Sertão) is characterized by a semi-arid climate, while the coastal areas receive more rainfall. This is the country's hottest climate, with an average temperature of over 25°C and rainfall of less than 600 mm. In this polygon of drought, "secas" (dry spells) can last more than half the year. In 1881, before the Canudos war, more than 100,000 people died as a result of this terrible drought in the Sertão region of Ceará. This region of the Nordeste, and the Nordeste in general, are considered Brazil's problem regions. For decades, flagelados (migrants), fleeing the terrible secas, have been heading for the region's metropolises or the megalopolis of São Paulo to try their luck, in search of a better existence. Such was the trajectory of former president Lula. Caatinga (sparse forest with small trees and cacti) is the typical vegetation of this region, where farmers struggle to make a living from extensive mixed farming. Since the 1970s, SUDENE has been implementing a development policy, including the creation of small dams known as "açudes". Global warming is making the seasons even more unpredictable. Droughts are getting longer and the rainy season shorter and more violent. This is undoubtedly one of the regions most steeped in history and character, and one that has inspired many writers, such as José de Alencar, Jorge Amado, Euclides da Cunha and João Guimarães Rosa.

A Brazil with ahigh-altitude tropical climate. Brazil is not often associated with mountains. It's true that Brazil is not an Andean country. In our traditional imagery, we may associate the notion of mountain with the Sugar Loaf or other morros (mornes) of Rio de Janeiro. However, travellers will certainly be led to visit plateau and mountain regions, as the development of ecotourism increasingly highlights these places of undeniable potential. Most of Brazil's high-altitude tropical climate is found in the Serras region of the Sudeste (states of Rio, São Paulo and Minas Gerais), or in the Chapada Diamantina (Bahia). Temperatures here are on average mild and moderate, with a fairly narrow temperature range (between 17 and 22°C) and regular rainfall of around 1,500 mm. However, winter nights can be chilly, and sweaters and blankets are appreciated in Ouro Preto, situated at an altitude of 1,100 metres, or in Campos do Jordão. Thunderstorms can also surprise hikers who haven't checked the weather forecast.

Southern Brazil, a subtropical Brazil. Brazil is a region where coffee has been replaced by grapevines, and where houses bear an uncanny resemblance to Bavarian chalets. While the second remark has nothing to do with climatic determinism, the presence of vines does indicate that the only climatic zone that is no longer truly tropical, but subtropical, is to be found in the south of the country, in the states of Santa Catarina and Rio Grande do Sul. The inhabitants of Rio Grande do Sul are called Gauchos, as in Argentina, because this prairie region is similar to the Pampa, and extensive livestock farming has developed here as in the neighboring country. The average temperature is 18°C. Winters (australs), which correspond to our summers, are cool and wet, with over 150 mm of precipitation in June, July and August. So it's a good idea to bring warm clothing, especially in the mountains, where temperatures can drop sharply and snow can fall in exceptional cases. Some hotels close in Florianόpolis during this season. More and more Brazilian tourists are choosing to go to Gramado or Canela, in the Serra Gaucha, to be sure of a real change of scenery, to have the impression of changing country while remaining in Brazil.

Brazil, a giant sensitive to global warming

A laboratory in the fight against global warming. Brazil is perhaps the most emblematic country in the fight against climate change. The impact of deforestation on the Amazon, the country's green lung, has been widely publicized around the world. Recently, numerous fires have ravaged the Amazon, as well as the Pantanal, a region less well known to the French, but which is extremely important due to the extreme richness of its biodiversity. The anti-environmental policies of the current Brazilian president, who is close to the agricultural lobby(bancada ruralista), were at the heart of a violent controversy between Bolsonaro and French President Emmanuel Macron. The latter advised the French to fight against imported deforestation by refusing to buy Brazilian GMO soya, produced on deforested land in the Amazon or the Cerrados of Mato Grosso. It's true that the IPCC experts are not very reassuring about the future of the Amazon. According to them, on the optimistic assumption of a warming of 1.1 to 2.6°C, based on a levelling off of the greenhouse gas emissions curve and therefore a limitation of warming, a large part of the Amazon forest (84%) should be able to regenerate in the long term. They explain this forest's extraordinary resilience by its biodiversity, which is far more diverse and rich than that of our temperate forests. As a result, this tropical rainforest and evergreen forest should resist global warming. Notable changes are nevertheless expected. Smaller species, less sensitive to water stress, should gradually replace the current dominant large trees. Some, however, consider this low hypothesis of global warming to be unrealistic. The (perhaps more realistic) assumption of continued uncontrolled greenhouse gas emissions, which would result in a much warmer atmosphere, would mean, according to the model developed, that only 13% of the Amazon basin would be able to regenerate, and would be powerless in the fight against climate change..

The impact of global warming is already evident. The time for change is now, Brazilian ecologists would unfortunately tend to say. Climate change is already having a major impact on Brazil. In February 2020, major floods hit the states of São Paulo and Minas Gerais, killing dozens of people. Previously, the state of São Paulo had suffered periods of drought of unusual intensity and length. The multiplication of extreme climatic events is thought to be the consequence of global warming. There is now talk of a permanent "El Niño" phenomenon. Ultimately, the risk of savannahization of the Amazon is inevitable. Moist air masses in the Amazon are becoming less regular, and the secas (dry seasons) are getting longer and longer. Soil degradation is making agriculture increasingly uncertain, and part of the endemic biodiversity is in danger of disappearing. As in many parts of the world, rising sea levels are accelerating coastal erosion. Part of the world's coastal metropolises are in danger of disappearing beneath the waters. The poorest neighborhoods are paying the heaviest price for rising sea levels. Anthropogenic deforestation and environmental degradation to produce polluting agriculture that benefits only a small number of people are contributing to the country's endangerment. Recently, a Swiss-Brazilian cooperation program led by Swiss researcher Gérard Moss, using a 300-metre-high tower installed north of Manaus, revealed a phenomenon known as "Flying Rivers". The researchers showed that aerosols emitted by Amazonian trees were at the root of gigantic air currents of water vapour that would influence the hygrometry of a large part of South America, far beyond the Amazon rainforest alone. Anthropogenic deforestation, or the reduction in the size of trees, could therefore accelerate the effects of climate change over a large part of the sub-continent.