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Brazil’s Great Amazon Rainforest Burns as Parched Megacities Fall Under Existential Threat
29
November, 2015
One
need only look at today’s satellite image of Brazil’s Amazon
Rainforest to notice something’s terribly wrong. A vast 1,000 mile
swath of what should be some of the wettest lands on the globe
running south of the world’s largest river is covered by a dense
pall of smoke. Scores of plumes boil up out of the burning and
sweltering forest. Pumping dark clouds into the sky, the fires’
tell-tale streaks out over a drought-parched Brazil, across the
Atlantic, and over to Africa where the plume is again thickened by
yet more wildfires.
(Massive
wildfires belch smoke over a vast section of Brazil’s Amazon
Rainforest. These fires are occurring as much of the country suffers
from drought. In the north, the current drought is the worst in at
least 50 years. In the southeast, drought is now said to be the worst
in at least 85 years. Image source: LANCE
MODIS.)
The
greatest rainforest in the world, sometimes called Earth’s lungs,
is burning, blackening, and belching out a thick pulse of carbon
dioxide into an atmosphere that is already greatly over-burdened with
industry-emitted greenhouse gasses. The world’s largest watershed
and remaining largest rainforest combined now finds itself in a
crisis of human making. A set of insults that may not now be
reversible as the forest begins to succumb to both drought and fire.
It’s
a crisis that threatens to turn South Brazil into a desert, to turn
one of the world’s vast carbon stores into a carbon emissions
source, and to eventually convert the great rainforest itself into
dry grasslands. Such a transition would result in yet one more major
contributor to increasing global greenhouse gas concentrations even
as it puts Brazil’s mega-cities under threat of collapse. And it’s
a transition that’s happening now. A violent transformation that
likely started during the early 2000s. One now reaching catastrophic
new intensities.
Human-Forced
Warming, Slash and Burn Agriculture, Godzilla El Nino
The
causes for the fires are three-fold and all too often missed in the
sparse mainstream media reports of the ongoing catastrophe. First,
human-caused warming of the globe is pushing the great rainforest to
slowly heat up and dry out. Alone, such warming would be enough to
take down the great rainforest if the Earth warmed by between 2 and 4
degrees Centigrade. Since we’ve already seen Earth System warming
on the order of 1 degree Celsius above 1880s values, the great forest
is now feeling the stress of this added heat. But the forest is now
also suffering the insults of what amounts to a half century of slash
and burn agriculture. Immense swaths of the forest have been cut and
burned away, converted into farmlands. Increasingly, large sections
of the forest are isolated into smaller, less productive islands. In
addition, the ongoing burning of vast tracts of woodland adds a fire
pressure to an already heat-stressed rainforest.
(The
Copernicus Atmospheric Monitoring System [CAMS] shows a significant
carbon dioxide plume rising up off of the fires now burning in the
Amazon Rainforest. It was a prediction made by global climate models
that human forced warming could turn the Amazon into a net carbon
emissions source by the middle of this Century. For the period of
Fall 2015, heat and drought have done exactly that. Image
source: CAMS.)
Finally,
this year, Brazil is experiencing the effects of what
is likely to become the strongest El Nino ever recorded.
Such Pacific Ocean warming events have a tendency to push the
rainforest to dry. And with the great Amazon already suffering from
at least a decade of drought, the new, extremely intense El Nino is
providing yet one more severe insult on top of all the other damage
inflicted by both human warming of the atmosphere and by slash and
burn agriculture.
Megacities
Suffering Severe Water Shortages
As
the Amazon rainforest suffers clear cutting, wildfire, and drought,
it pumps less and less water into the atmosphere. Its
once massive ‘flying rivers’ are drying out.
The loss of these immense atmospheric moisture flows has a
particularly acute impact on lands bordering the Amazon —
especially in the region of Brazil’s coastal cities. Over the past
two decades, the massive cities of Sao Paulo and Rio de Janeiro have
suffered from increasingly frequent droughts. However, over the past
three years, drought has been particularly extreme.
In
Sao Paulo, unofficial water rationing began about two years ago and
has remained in effect ever since. Today, the region’s largest
reservoir — the Cantariera — remains below dead pool levels even
as other reservoirs have fallen under increasing stress. The result
is that many
of the area’s 20 million people are starting to migrate to cities
with better water security.
Cities like Jundiai where water conservation policies have prevented
shortages despite an ongoing drying of the surrounding countryside.
(In
the July-September 2015 rainfall graphic measure provided by NOAA, we
see the Amazon Rainforest experiencing severe water deficits in
conjunction with the warmest global temperatures on record and what
is likely to become the strongest El Nino on record. A heat pressure
that has resulted in severe wildfire outbreaks throughout the Amazon
this month. Such impacts will further reduce the moisture content of
the flying rivers the cities of Southern Brazil depend on. Image
source: NOAA’s
Climate Prediction Center.)
In
Rio de Janeiro, the situation is still somewhat better than in Sao
Paulo. Water cut-offs have not yet begun in this city of 10 million
even though local reservoirs are also starting to dry up. But if dry
conditions continue, 2016-2017 will almost certainly see Brazil’s
second largest city fall into a crisis similar to that of Sao Paulo.
A
recent report by NPR highlights
the severity of Brazil’s coastal cities drought:
And [Sao Paulo] is not alone. Brazil’s second largest city, Rio de Janeiro, is also facing water troubles, as are other coastal areas. It’s been an enormous shock to Brazilians, who are used to their country being called “the Saudi Arabia of Water…” But not anymore. Satellite data from NASA shows that the drought in much of southeast Brazil — also home to the region’s breadbasket — is much worse than originally believed.
If
these droughts continue, they will threaten to collapse the cities of
eastern Brazil. They will put a strain on electricity supplies, on
commercial activity, and on practically every aspect of city life —
which is largely dependent upon access to water. In eastern Brazil,
more than 30 million people now face the threat of this climate
change induced destabilization. But what’s worse is the fact that
the ongoing burning and drought in the Amazon to the north
practically ensures that the flying rivers will continue to wilt,
that the droughts in the southeast will grow to become city-killers.
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