We’ve been having a heat wave in California, and the worst drought in
recorded history. Normally around November 1 I put the hardtop on the roadster
and pack it away for the winter, but not this year. With no rain and highs in the 80s, I’m still
driving it. On TV I saw the Australian
Open also had record triple digit temperatures.
Meanwhile, something dubbed the Polar Vortex, an unusual subsidence of
the jet stream, brought record cold to the Midwest
and Northeast. The weather, in short, is
screwed up, and we’re the reason. By
dumping increasing volumes of greenhouse gases (CO2 and methane) into the atmosphere we’re raising
average global surface temperature and changing global climate dynamics. The surface temperature of the earth has
increased 1.4° over the past century.
That may not seem like much, but 2/3 of the increase occurred in the
past 30 years, so the rate of increase is accelerating. In addition, recent research on cloud
formation suggests the rate of warming may be more rapid than previously
estimated. CO2 in the atmosphere recently passed 400 parts
per million, a concentration not seen since 4.5 million years ago, an era long
before the advent of humanity when sea levels were 50 feet higher than they are
today. Unless we put the brakes on
emissions the concentration could reach 1000 ppm by 2100, and CO2 has a lifetime of a century or more. The climate is a complicated system, too
complicated for us to be able to model exactly what the detailed results of
such a change will be, but that much CO2 in the atmosphere could cause global surface
temperatures to surge 7° by 2050, 14° by 2100.
Warming of that magnitude will produce a catastrophic rise in sea
levels, inundating coastal areas. The
increased heat energy in the climate system will produce extreme weather events
of a magnitude hardly dreamed of today.
Subtropical deserts will expand and crop yields will fall substantially,
bringing about widespread famine. Ocean
acidification will kill coral and shellfish.
Unmitigated climate change on this scale could exceed our capacity to
adapt. To search for more fossil fuels
under these circumstances is a fool’s errand.
If the fossil fuel already available were burned the planet would be rendered unlivable. Burning it would be
suicidal, yet the energy companies are still searching for more.
As bad as climate change is, it’s only part of the picture,
one aspect of the great extinction we are engineering. Humans have been having an impact on the
ecosystem we inhabit for at least 10,000 years.
Killing off megafauna like the mammoths and mastodons was just the
beginning. Now we’re in the midst of an
extinction that’s shaping up to be even larger than the one that killed off the
dinosaurs, only this time the asteroid is us.
10,000 years ago humans and their domesticated animals represented .1%
of the vertebrate life on earth. Today
we represent 95%. We are displacing all
other species. As our numbers continue
to explode, we move into every available nook and cranny of the world carrying
species of plants and animals with us that replace the native flora and fauna. Weed species, like rats and cockroaches,
proliferate. We plow native grasses
under to plant row crops, separate what were once contiguous forests into isolated
groves. We modify or destroy vast tracts
of land and river systems in order to meet human ends. 15% of the earth’s surface has been converted
to industrial uses or row-crops, with another 8% being used for pasture,
ruining local ecosystems. The oceans are
over-fished, millions of tons of by-catch are simply discarded. We are depleting natural resources at a
prodigious rate. Through habitat
encroachment, destruction or fragmentation, hunting, pollution, climate change,
the spread of disease, and the introduction of nonnative species we are
exterminating animal and plant life on earth at a rate 100 times greater than
any massive extinction event of the past, and the rate is accelerating. It’s estimated that by 2050 30% of the
species currently inhabiting our planet will be extinct. 50% of current higher life forms will be
extinct by 2100. Biodiversity is
declining rapidly. Whole lines of phyla
are being lost. And we are the
cause.
The greatest extinction event we know of, dubbed “The Great
Dying,” occurred 252 million years ago.
On that occasion CO2 levels got so high that
the surface ocean temperature reached 104° and the ocean became anoxic, killing
nearly all higher sea life. The oxygen
depletion allowed sulfate-producing bacteria to thrive, producing hydrogen sulfide
that belched into the atmosphere, poisoning land animals and plants and
weakening the ozone layer so that any land life that remained was exposed to
fatal levels of UV radiation. Of course,
extinction, even a massive extinction like this one, is part of the
evolutionary process. Mass extinctions
eliminate the dominant species to allow newcomers to proliferate and
flourish. If the dinosaurs hadn’t been
eliminated, there wouldn’t have been an opportunity for mammals, for us. But when we are the dominant species that may
be eliminated it puts a different light on it.
As a human, I don’t want us replaced.
And, in the short run, the loss of all the other species that we have,
as it were, grown up with, impoverishes our existence.
Human population growth is the fundamental cause of the potential
catastrophe we are facing. We are overrunning
the planet and destroying everything in our path, not just animals but plants
as well. The earth does not have the
capacity to absorb our wastes. If we do
not reduce our population, widespread famine and starvation will do it for
us. And yet economists, bizarrely, continue
to speak of growth, infinite growth.
We are currently doing far more to endanger ourselves than
we are to ensure our survival. Sooner or
later, and it’s looking more and more like sooner, we will face a global cataclysm
in which our survival will be at stake. If
we want to continue as a species, we need to limit the damage we are doing as
much as possible, as soon as possible, wean ourselves from finite resources,
sharply limit emissions of greenhouse gases, and, most importantly, strive for
Zero Population Growth or, better yet, Less Than Zero. Nothing would do as much to heal the planet
as reducing the number of humans. If we
would just stop breeding like rabbits, slow down to 1 child per woman, the
planet could begin to recover. But, of
course, that’s not going to happen.
