By David L. Brown
The latest nightmare of potential global warming comes in a report from the prestigious Woods Hole Research Center. According to a recent study (hat tip to Climate Ark), the Amazon basin, home ot the world’s largest rain forest, may be on the verge of becoming a desert.
Quoting a story in the British newspaper The Independent, Climate Ark points out that this would have:
…catastrophic consequences for the world’s climate. [The scientists] predict the Amazon rainforest cannot withstand more than two consecutive years of drought without “mega-fires” sweeping across the drying jungle, destroying healthy rainforest ecosystems, and resultant denuded soil baking in the sun ultimately becoming a desert. The Amazon is now entering its second successive year of climate change intensified drought, making it likely that widespread forest die-back will start soon. The Amazon rainforests contain 90 billion tons of carbon, enough to increase the rate of global warming by 50 percent.
As Star Phoenix Base recently reported (see “Revenge of Gaia: A Modern Horror Story,” posted July 23), a total rise of ocean surface temperatures of just 4 degrees C. would be sufficient to destroy the Amazonian rain forest, turning the “lungs of the planet” into a wasteland of scrub brush and desert. We now see evidence that just such an event may not only be possible, it may be taking place at this very moment as global temperatures continue to climb.
According to the article in The Independent, as reported by Climate Ark:
The research carried out by the Massachusetts-based Woods Hole centre in Santarem on the Amazon river has taken even the scientists conducting it by surprise. When Dr Dan Nepstead started the experiment in 2002 by covering a chunk of rainforest the size of a football pitch with plastic panels to see how it would cope without rain he surrounded it with sophisticated sensors, expecting to record only minor changes.
The trees managed the first year of drought without difficulty. In the second year, they sunk their roots deeper to find moisture, but survived. But in year three, they started dying. Beginning with the tallest the trees started to come crashing down, exposing the forest floor to the drying sun.
By the end of the year the trees had released more than two-thirds of the carbon dioxide they have stored during their lives, helping to act as a break on global warming. Instead they began accelerating the climate change.
The article went on to report that researchers predict that the loss of the Amazon forest would “spread drought into the northern hemisphere, including Britain, and could massively accelerate global warming with incalculable consequences, spinning out of control, a process that might end in the world becoming uninhabitable.” Truly ominous words.
The results of such a catastrophe cannot be overestimated and would have profound effects on the Earth’s climate. The potential imminent destruction of the Amazon Basin forest joins a growing list of unexpected “tipping points” or feedback effects about which we have written so much. These events include the rapid melting of the Arctic ice cover; signs that the Greenland ice sheet may be in the beginning stage of break-up; deterioration of the Antarctic ice with rapid collapse of major ice sheets; signs of possible disruption of the Atlantic thermohaline conveyor; increasing frequency and intensity of hurricanes, typhoons and cyclones; and, of course, the steady measured increase of greenhouse gas (GHG) in the atmosphere with the resulting rise in oceanic and atmospheric temperatures.
All of these and more are known potential dangers, and each has evidence to suggest that they are already beginning to take place. To add to the grief, each event will come with its own feedback effects, multiplying the dangers. For example, the loss of the Arctic Ocean’s ice cover will allow far more solar energy to be absorbed by the water instead of being reflected back into space. That will create a rapid warming, which in turn will accelerate already on-going melting of tundra and permafrost in the far north. That in turn will release large quantities of methane, a powerful GHG 24 times more potent than CO2, thus increasing overall global warming. The melted tundra will sprout deciduous bushes and trees whose dark leaves will absorb even more solar heat and further warming the region. Warmer Arctic Ocean waters may also affect the Atlantic thermohaline conveyor (which has its own ensemble of disastrous effects), and could also result in the melting of frozen methane sequestered on the sea bottom as clathrates. Again, each effect has its own effects, which could lead to other effects like rows of falling dominoes, feedback upon feedback in a runaway environmental collapse.
The possibility of catastrophic runaway global warming is becoming more real with every passing day. Events such as this summer’s unusual heat waves in the Bay Area, Germany and England are only small samplings of what may lie in store for our planet. If something as important as the Amazonian rain forest could be on the very edge of sudden death, what horrors await us as even more unexpected effects could soon threaten our planet’s environment and human civilization itself? And, of course, the threat is not limited to the Brazilian ecosystem. We see increasing numbers of forest fires and tree death across North America, and what of those two other major rain forests in Africa and Indonesia? Surely this is a global event that will affect every place on Earth.
Clearly, climate change is not only real, it is unfolding at a rapidly increasing rate. A few faint voices in the wilderness have been trying to warn us of the danger for decades, and now it may be too late to do anything more than watch the disaster unfold. We speak of canaries in coal mines, but if the Amazon rainforest should succumb it would be a far more serious warning of terrible troubles ahead for humanity and our planet. Less like the death of a canary than an enormous flock of environmental chickens coming home to roost.