SÃO PAULO — When it comes to freshwater, Brazil, home to somewhere between 12% and 16% of the world’s total supply, is a very wealthy country.
Inhabitants only use 0.7% of the 43,000 cubic meters of water per year that could, theoretically, be available to each and every one of them. In this regard, Brazil contrasts sharply with places like Algeria and Palestine, which use nearly half of their available resources, or Saudi Arabia and the United Arab Emirates, which have to desalinate seawater to meet their needs.
Brazil’s situation is not, however, quite as enviable as it would seem. The first problem lies in the location of these resources. Water is most abundant in the uninhabited parts of the country and in the most protected forests, particularly in the Amazon, but is in short supply where it is most needed, namely the southeast and northeast regions, home to 70% of the population.
Supply problems have been complicated further still by this year’s drought in São Paulo. Another serious drought — in Brazil’s semi-arid region — occurred between 2012-2013.
Changing weather patterns due to climate change could make matters even worse. Because of increasing emissions of CO2 and other so-called greenhouse gases, the Earth’s atmosphere retains more heat close to its surface, causing the temperatures of higher air masses to increase.
The energy contained in the atmosphere is what fuels the winds and the storms. Climate simulations predict that additional radiation will alter circulation patterns. As a result, some regions could see more frequent and more severe droughts while others will be faced with floods that might also be more intense during abnormal rain episodes.
The Brazilian Panel on Climate Change (PBMC), a committee representing some of the country’s top climatology experts, has come up with its own projections of what the climate could be like in Brazil’s various regions.
The panel predicts that by the end of the century, temperatures in the Amazon could jump 5 to 6 degrees Celsius and that precipitation could decrease by 40% to 45%, with a 10% drop already in the next five years. Temperatures in the northeast region could rise 3.5 to 4.5 degrees, with a 50% drop off in precipitation, and in the south, temperatures could rise 3 degrees with a 35% to 40% increase in rainfall, according to the PBMC.
Researchers cannot say with certainty whether the recent drought episodes in the southeast and northeast regions, or the tragic floods that affected Rondônia state earlier this year, are directly connected to climate change, either globally or locally. But the possibility cannot be ruled out either.
What is certain is that these disasters — and the heavy economic costs they imply — are a good demonstration of what we can expect in the coming decades assuming global warming worsens. They are also a reminder that Brazil, despite its current water wealth, must do more to adapt to the challenges, which will affect one of the most basic human needs: water to drink, to clean and to plant.