How South Americans are Killing Their Environment

In some places, cutting down trees can have huge consequences.  In South America, the impacts are especially far-reaching.  Deforestation has picked up again in the Amazon.  That, in turn, is causing havoc to the region's hydrological cycle, triggering severe drought.

The unprecedented drought now affecting São Paulo, South America’s giant metropolis, is believed to be caused by the absence of the “flying rivers” − the vapour clouds from the Amazon that normally bring rain to the centre and south of Brazil.

Some Brazilian scientists say the absence of rain that has dried up rivers and reservoirs in central and southeast Brazil is not just a quirk of nature, but a change brought about by a combination of the continuing deforestation of the Amazon and global warming.

This combination, they say, is reducing the role of the Amazon rainforest as a giant “water pump”, releasing billions of litres of humidity from the trees into the air in the form of vapour.

...Deforestation all over Brazil has reached alarming proportions: 22% of the Amazon rainforest (an area larger than Portugal, Italy and Germany combined), 47% of the Cerrado in central Brazil, and 91.5% of the Atlantic forest that used to cover the entire length of the coastal area.

...As long ago as 2009, Antonio Nobre, one of Brazil’s leading climate scientists, warned that, without the “flying rivers”, the area that produces 70% of South America’s GNP would be desert.
In an interview with the journal Valor Economica, he said: “Destroying the Amazon to advance the agricultural frontier is like shooting yourself in the foot. The Amazon is a gigantic hydrological pump that brings the humidity of the Atlantic Ocean into the continent and guarantees the irrigation of the region.”

“Of course, we need agriculture,” he said. “But without trees there would be no water, and without water there is no food.

“A tonne of soy takes several tonnes of water to produce. When we export soy we are exporting fresh water to countries that don’t have this rain and can’t produce. It is the same with cotton, with ethanol. Water is the main agricultural input. If it weren’t, the Sahara would be green, because it has extremely fertile soil.”

Drought visits all manner of consequences on Brazil.  Sao Paulo, a city of 9-million, is facing the prospect of running out of water within just two or three months.  Brazil has also been the second-largest hydroelectric power generator in the world.  Now it's power infrastructure undermined by drought, Brazil is trying to shift to wind power.  In the meantime, as Brazil's hydro-electric generation falters, the country is left to turn to fossil fuel-powered generation.

Two years ago, hydroelectric power accounted for 89 percent of electricity production from January to July, while fossil fuels accounted for 7.3 percent of the mix. This year, hydroelectric is down to about 75 percent of the total, with fossil fuels rising to about 22 percent, Valor Economico said, citing data from the national electricity operator.

As for the future of the Amazon, the fear is that deforestation could so alter the environment that the rainforest dries up, dies, and then begins its own natural feedback mechanism - wildfires.  Unlike temperate forests, the trees of the Amazon have no resistance to fire.

Nature's Version of Waterboarding

Think of it as the difference between a refreshing drink of water and undergoing waterboarding.   We used to expect the former from nature but now, all too often, it's the latter.

Las Vegas is an object lesson.   The desert city is now forced to drain its essential freshwater from a distant corner of the state via a canal system.   Until nature shows up but then it's often in the form of deluge triggering flash floods.

The city, that averages 4.5 inches of rain annually, got hit with a 1.75 inch downpour that left parts of the city flooded, like this parking lot at the University of Nevada, Las Vegas:

The floods have hit various spots throughout the American southwest.   Yet this sort of urban flooding is now established world wide.   Many municipal storm sewer systems are not designed to handle the sort of rainfall patterns they're now experiencing.  Runoff becomes concentrated and backs up, resulting in heavy flooding.   From Britain to the Philippines to China to the United States and elsewhere, heavy flooding is becoming commonplace.

Many of these areas are also beset by sustained drought that can harden the ground and make it impervious.   Then, when floodwaters arrive, they don't seep into the ground but simply run off into what the Mexicans call arroyos, normally empty streambeds carved out by centuries of flash flooding.

Today's floods, just like today's droughts, evidence our broken hydrological cycle.   Surface temperatures warm, increasing evaporation.   Atmospheric temperatures warm, increasing volumes of water vapour, itself a powerful greenhouse gas.   Warmer, wetter conditions create more atmospheric energy that results in erratic precipitation patterns and severe storm events of increasing frequency and intensity.   Some regions get hit by torrential rains, others are bypassed and experience drought.

This is occuring this year in most of the world's greatest grain producing countries - the United States, Australia and Russia in particular.   Food prices globally are already spiking.  A continuation of this threat will destabilize already wobbly countries around the world.

Predictable, reliable and moderate rainfall has been a vital part of mankind's introduction of agriculture that, in turn, facilitated the rise of civilization.   With but a few exceptions, farmers could count on receiving the right amounts of rainfall at the right times throughout the planting/growing/harvest cycle.   Too much rain or too little rain at any stage and the crop might fail.

Despite demographic predictions that the world population will reach 9-billion by 2050, perhaps 15-billion by 2100, the hydrological cycle problem could make those projections unrealistic.  At 7-billion, mankind's ecological footprint is already placing us in a severe "overshoot" deficit.   World Overshoot Day this year fell on August 22nd, several weeks earlier than just a few years ago.  In effect, mankind now uses a full year's worth of the Earth's renewable resources before the end of August, leaving us to "eat our seed corn" for the balance of the year.   This deficit is only going to be worsened by disruptions in agricultural production from droughts and floods.

We are being overtaken by events.   The theme of Gwynne Dyer's latest column could be "nobody saw it coming."  But it's here and we're going to have to find ways to live with it - better systems to collect and hold rainwater, curbs to water usage and wastage, improved agriculture and food distribution, for starters.   We're also going to have to realistically price carbon to whatever extent necessary to decarbonize our economies and our societies.  Above all else we'll need to develop technologies to strip atmospheric carbon in massive amounts.

For mankind this is likely the fight of our lives.   Yet that is still a far cry better than having to fight for our lives.

The Raincoast May Be Getting Wetter

Coastal British Columbia may not be a great place to live if you have problems coping with rain.   We have what I like to call the "Rain Festival" that runs from around mid-October until somewhere between June and July.   Lard, Jaysus and Tunder but it can get wet.  New research is showing that it's probably going to get wetter yet.

"Warmer air allows for more water vapor. So scientists have long predicted that global warming will result in a more intense water cycle—the process by which water evaporates from the oceans, travels through the atmosphere and then falls as rain. Now new measurements of the ocean's salinity prove that prediction—and suggest that global warming strengthens the water cycle even more than anticipated.

"'What we found is that regions that are salty in the main are becoming saltier' and areas that boast more rainfall are getting fresher, explains oceanographer Paul Durack of Lawrence Livermore National Laboratory, who led the research to be published in Science on April 27. 'It's another independent estimate of how the climate is changing as we pump out CO2.'"

What's the best way to cope with what can seem like interminable rainfall?  The internet.  Just go on line and read about all the places that should be getting all that extra rain but aren't.   Read about the people there and what doing without that extra rain does to their lives.  Imagine what they would give to trade places with you.  Just do that and you find you've suddenly got nothing at all to bitch about.

Extending data from 3,500 sensor buoys received over the past decade, "to the millions of historical salinity readings from 1950 to 2000 reveals that, as predicted, evaporation strengthened in drier regions—making the oceans saltier there—and rainfall strengthened in wetter regions—making the surface seawater fresher. In fact, global warming of roughly 0.5 degree Celsius over that span strengthened the water cycle by roughly 4 percent, or around the amount predicted by physicists' equations. "Through a lot of investigation, it provides us with what we would have guessed," Durack says.
 
But that's not what scientists' computer models predicted. Though various computer models match the actual distribution of saltier and fresher regions quite well, the computer models underestimated the actual rate of water cycle intensification by half. That suggests that impacts on the water cycle of future warming of several degrees Celsius could be substantial, strengthening rainfall and evaporation by as much as 24 percent.

The stronger water cycle will mean stronger rains and intensified droughts over the oceans. And what holds at sea also extends over land, because the oceans cover 71 percent of the globe, hold 97 percent of the world's water, and have already sucked up 90 percent of the extra heat trapped by humanity's greenhouse gas pollution. The increase in warm water vapor as the globe heats will fuel more violent storms, whereas droughts in places like Australia, stuck in the middle of oceanic regions dominated by evaporation, will only grow more severe. Or as Durack says: "wet regions will get wetter and dry regions drier." Given that freshwater availability affects everything from food to energy, this may prove a more difficult challenge for human civilization and natural ecosystems to adapt to than that posed by global warming itself.