University of São Paulo: Brazil Braces for Dry and Hot Winter, Meteorologists Warn
After the hottest May ever recorded on the planet, Brazil is entering its winter. However, the feeling will be of a mild summer, as the disproportionate heat for the period is expected to continue. In addition, the drought, which despite being common for this season of the year in the region below the equator, is expected to be much more intense here. Pedro Luiz Côrtes, a professor at the Institute of Energy and Environment at USP, explains that this is a combination of global climate deregulation and deforestation in the Amazon.
Global effect
The current moment is one of transition between the end of El Niño and the beginning of La Niña, which should begin in the middle of the year. Although this period may suggest neutrality, the professor says it is not: “We still have repercussions of El Niño in the South, with rains still persisting, although in smaller volumes, and we already have the repercussions of a La Niña in formation with rains in the region in the extreme North”.
El Niño brings heavy rains to the South and droughts to the North. Last year, the Amazon experienced a very intense drought, and La Niña, which is now arriving, does the opposite: drought in the South and more intense rains in the North. With this contradictory combination of factors, Côrtes states that “the forecast indicates that this winter will be dominated by dry and hot weather in the central region of the country”. A certain normality may be seen on the coast of the Northeast, in the North region and some cold fronts may enter São Paulo, but they will be contained.
While the drought may initially be welcomed in the South, given the disasters caused by excess rain, the expert urges caution: “It could be a good thing at the moment, but not over the next two years, for example. If this La Niña lasts two or three years like the last one, it could really harm the recovery of certain crops.”
Logging
According to Côrtes, we are reaping the negative results of the Amazon fires of recent years – in addition to, of course, the entire historical process of deforestation. He explains, detailing the process of how rain reaches the North, the Center-West, South and Southeast: “We have all the moisture from the Equatorial Atlantic Ocean being pushed by the trade winds, from east to west, into the interior of the Amazon rainforest. This precipitates in the form of rain and hydrates the deep subsoil. The large trees, which have deep roots, recover this moisture, drain this water from the subsoil and replenish the moisture in the atmosphere through evapotranspiration.”
This process repeats itself, spreading throughout the forest, until the winds meet the Andes, and a significant part of them makes a turn and distributes this moisture to the south of the continent. The amount of moisture coming from the Amazon is decreasing due to deforestation, because it breaks this cycle of recycling moisture within the forest and, consequently, its distribution to the rest of the country. “It is no surprise that the driest part of the Amazon at this moment is precisely the most deforested area,” says Côrtes.