Five years ago, the tropical forest not only suffered the stiffest drought ever heard of but new research shows that a major storm felled thousands of trees, a sample of just how vulnerable the Amazon Rainforest is becoming to extreme climatic phenomena.

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In her novel “O quinze” (The Fifteens), writer Raquel de Queiroz, born in Ceará, tells of the major drought which ravaged Brazil’s northeast wilderness in the year of 1915, resulting in a scenario of famine, poverty and aridity of the Caatinga, a typical vegetation of this region. Almost 100 years later, in the year of 2005, the Amazon Rainforest also experienced its epic drought. In times of globalization and climate changes, pictures of a dried out Amazon River, with several boats aground, dead fish and desolate riparian dwellers, spread throughout the world, astonishing viewers worldwide.

The dramatic imagery of drought in a region known for being one of the most abundant in the world regarding water, ended up overshadowing another extreme weather phenomenon that occurred in the Amazon Rainforest in that same year of 2005.

A strong tropic storm with winds up to 145 kilometers an hour swept through the entire Amazon Basin between January 16 and 18 from Southwest to the Northeast, leaving behind casualties mainly in the cities of Manaus, Santarém and Manacapuru. It was a very uncommon natural phenomena for that region: a storm coming from the South and not from the East, as it normally occurs, explains the researcher from INPA (National Institute for Amazonian Research), Bruce Walker Nelson.

Now, five years later, a scientific study disclosed by the American Geophysical Union (AGU) with support from NASA (United States’ National Aeronautics and Space Administration) and with the participation of INPA, brings up the impacts of this major storm on the forest: “between 441 and 663 million trees were destroyed in the entire Amazon Basin”. Large trees fell and dragged down others such as with a domino effect, revealing the forest’s vulnerability to extreme climate variations.

This study challenges a previous one published in Science magazine last year that pointed solely to the drought as the major reason for the increase in the death of trees in 2005. Researchers noticed from satellite photos, that even in regions that were not affected by the drought, such as Manaus, there was a significant number of destroyed trees, estimated between 300 and 500 thousand trees, a number above even those ravaged by drought.


With field work, scientists identified the destruction caused by wind gusts, known as downbursts by meteorologists, meaning “winds that come down and burst upon the surface”, like tornadoes. “If a tree dies due to drought, it usually dies still upright. Trees that die due to storms are quite different as they are uprooted”, points out one of the authors of the study, ecologist Jeffrey Chambers, who analyzes the carbon cycles of the Amazon since 1993.

Carbon cycles

With such a tremendous loss of trees, the research suggests that extreme tropical storms can play a much more important role in forest life than previously imagined. The carbon cycle, for instance, can be affected a great deal in the more drastic cases, although it is a little early to ascertain the size of this impact. From an average of how much CO2 a tree absorbs, researchers estimate that the forest retained some 23% less carbon in 2005 than its usual annual capacity, due to the storm alone.  

There is the fear that such inclement weather may become more frequent in the future of the Amazon Rainforest due to climate changes, killing greater numbers of trees and releasing even more carbon into the atmosphere. “Deforesting caused by Man, plus extreme natural phenomena, can accelerate and anticipate scenarios of unbalance in the Amazon Rainforest, such as the transforming of forests into savannahs, foreseen in consequence of the increasing global warming”, highlights climatologist and researcher José Marengo from INPE in an interview for ((o))eco.

Marengo, who is one of Brazil’s major climate experts, emphasizes the importance of better understanding the impacts of an extreme climate phenomenon on the vegetation and carbon cycle. However, he says that there are still many uncertainties hovering over this theme and that this is not a conclusive study. The research employed a model to estimate the amount of dead trees within the entire area affected by the storm (some 9 thousand square kilometers), based on the analysis conducted in the region of Manaus. In this manner, it is possible to have a relatively high margin of error, as Bruce Nelson, INPA’s researcher, also pointed out.

On one side, storms and droughts. On the other, human beings, still the major cause of deforesting. These are major pressure factors that threaten the survival of the Amazon Rainforest. Nevertheless, nature’s resilience is enormous and the forest can regenerate itself as long as human beings cooperate towards its preservation. In Raquel de Quiroz’s novel, the drought of 1915 brought about moral conflicts that made its characters refrain from fooling themselves in the name of illusions and weaknesses, in order to overcome their problems. Will life mimic art in time to avoid the worst?


Juliana Radler is a journalist with a specialization in the environment by the International Institute of Journalism (IIJ), of Berlin. She is a collaborator of the German magazine Development and Cooperation (D+C) in Brazil, of the ((o))eco Portal and serves as a director and editor of the video production company, Sumaúma, in Rio de Janeiro.