Parched Amazon – 10/07/2023 – Reinaldo José Lopes

The easiest reaction to the sad scenes of recent days in the Amazon is to attribute them to bad luck. More than a hundred dolphins that died “cooked” by the heat of the lake water? A misfortune, but extreme temperatures and drought do happen from time to time. It’s life, people.

There is no reason to believe that this is all that is happening, however. Yes, there is a component of chance, or “noise”, inherent to the climate system, which leads to variations capable of producing extreme events. But several non-random factors have come together to weaken Amazon ecosystems.

If we compare the forest to a piece of green armor, the inevitable conclusion is that holes have been appearing in it with increasing frequency — holes through which the arrows of climate disaster can pass with increasing ease.

I wrote at the beginning of this year about two of the most complete diagnoses of the problem so far, signed by researchers such as Carlos Nobre, from USP, and David Lapola, from Unicamp. These analyzes demonstrate, for example, that extreme climate events — both devastating droughts and out-of-control floods — have hit the Amazon region in 9 of the last 15 years. This is more than all similar situations (only 7) during the entire 20th century.

A considerable part behind this frightening change comes from the increase in the planet’s average temperature (about 1.1ºC so far), produced by the burning of fossil fuels. The Amazon is a region whose normal temperatures are no longer far from the limit that animals and plants can tolerate well, which means that changes of this type push the situation closer to intolerable.

More local effects, however, are equally important, in addition to feeding back global dangers. In general, we can say that unrestrained exploitation since the second half of the last century has eaten the forest at the edges — it is the famous arc of deforestation, which stretches from the southeast of Pará towards Rondônia and Acre.

This process of “eating around the edges” has first affected the relatively drier and more seasonal areas (that is, with greater variation between seasons) of the biome. More deforested and/or burned, these forest areas are undergoing a process of weakening their ability to resist fires and recycle rain.

This second point is very important, since around half of the 14.1 trillion cubic meters of rain that usually (or perhaps, better said, used to) fall in the region every year are catalyzed by the forest itself, which emits particles around the which clouds form. There is no way to remove the forest and expect the climate, at a local and regional level (not to mention global) to remain the same, therefore.

Now, think of these processes as a kind of domino effect. The forests that disappear in the arc of deforestation leave areas of the biome that previously only had contact with other sections of the forest unguarded and exposed to the effects of the agricultural frontier. The cycle repeats itself: more vulnerability to fire, less ease of recycling water — and a new row of dominoes falls.

It is no coincidence that there is fear that the Amazon biome will reach a point of no return: a moment in which significant portions of it will stop behaving functionally like a forest — with all the biological and climatic interactions that this implies — and will transform into in savanna. If this happens, there will be no air conditioning in the world capable of transforming Manaus and Belém into habitable cities, or of making agriculture in the region viable — the same thing that, today, is part of the problem. The first step to avoiding the worst-case scenario is to recognize that, for now, we are collaborating to build it, brick by brick into a tragic wall.

LINK PRESENT: Did you like this text? Subscribers can access five free accesses from any link per day. Just click the blue F below.