Reflections on the Surface

July 10, 2007

Wildfires in the West

Filed under: Environment,global warming,insanity,Life,Nature,Thoughts — asharpminor @ 12:47 pm

London, England.
Wildfires in the West of the USA have afflicted at least ten states ranging from Idaho to New Mexico as the region swelters under a raging heat.
Meanwhile, thousands of acres of Brazilian rain forest are being burnt into charcoal.

For those of us who care about such things but who don’t have ‘time’ to read Mark Lynas’ book: ‘Six Degrees, Our Future on a Hotter Planet’, here is a summary of what we are to expect for the first three degrees of global warming. (Courtesy of Mark Lynas and the Guardian Newspaper)
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‘Six steps to hell’ – summary of SixDegrees as published in the Guardian 23 April 07
By the end of the century, the Earth could be more than 6C hotter than it is today, according
to the Intergovernmental Panel on Climate Change. We know that would be bad news – but
just how bad? How big a rise will it take for the Alps to melt, the oceans to die and desert to
conquer Europe and the Americas? Mark Lynas sifted through thousands of scientific papers
for his new book on global warming. This is what the research told him…

The following is an article by Mark Lynas based on his book Six Degrees: Our Future on a
Hotter Planet. It was published in the Guardian on 23 April 2007. The original version is
available here.
1ºC
Nebraska isn’t at the top of most tourists’ to-do lists. However, this dreary expanse of
impossibly flat plains sits in the middle of one of the most productive agricultural systems
on Earth. Beef and corn dominate the economy, and the Sand Hills region – where low, grassy
hillocks rise up from the flatlands – has some of the best cattle ranching in the whole US. But
scratch beneath the grass and you will find, as the name suggests, not soil but sand. These
innocuous-looking hills were once desert, part of an immense system of sand dunes that
spread across the Great Plains from Texas in the south to the Canadian prairies in the north.
Six thousand years ago, when temperatures were about 1C warmer than today in the US,
these deserts may have looked much as the Sahara does today. As global warming bites, the
western US could once again be plagued by perennial drought – devastating agriculture and
driving out human inhabitants on a scale far larger than the 1930s “Dustbowl” exodus.
On the other side of the Atlantic, today’s hottest desert could be seeing a wetter future in
the one-degree world. At the same time as sand dunes were blowing across the western US,
the central Sahara was a veritable Garden of Eden as rock paintings of elephants, giraffes and
buffalo, also dating from 6,000 years ago, attest. On the borders of what is today Chad,
Nigeria and Cameroon, the prehistoric Lake Mega-Chad spread over an area only slightly
smaller than the Caspian Sea does now. Could a resurgent north African monsoon drive
rainfall back into the Sahara in a one-degree world? Models suggest it could.
Also in Africa, Mount Kilimanjaro will be losing the last of its snow and ice as temperatures
rise, leaving the entire continent ice-free for the first time in at least 11,000 years. The Alps,
too, will be melting, releasing deadly giant landslides as thawing permafrost removes the
“glue” that holds the peaks together. In the Arctic, temperatures will rise far higher than the
one-degree global average, continuing the rapid decline in sea ice that scientists have
already observed. This spells bad news for polar bears, walruses and ringed seals – species
that are effectively pushed off the top of the planet as warming shrinks cold areas closer and
closer to the pole.
Indeed, it is the ecological effects of warming that may be most apparent at one degree.
Critically, this temperature rise may wipe out the majority of the world’s tropical coral reefs,
devastating marine biodiversity. Most of the Great Barrier Reef will be dead.

2ºC
In the highly unlikely event that global warming deniers prove to be right, we will still have to
worry about carbon dioxide, because it dissolves in the oceans and makes them more acidic.
Even with relatively low emissions, large areas of the southern oceans and parts of the Pacific
will within a few decades become toxic to organisms with calcium carbonate shells, for the
simple reason that the acidic seawater will dissolve them. Many species of plankton – the
basis of the marine food chain and essential for the sustenance of higher creatures, from
mackerel to baleen whales – will be wiped out, and the more acidic seawater may be the
knockout blow for what remains of the world’s coral reefs. The oceans may become the new
deserts as the world’s temperatures reach 2C above today’s.
Two degrees may not sound like much, but it is enough to make every European summer as
hot as 2003, when 30,000 people died from heatstroke. That means extreme summers will
be much hotter still. As Middle East-style temperatures sweep across Europe, the death toll
may reach into the hundreds of thousands. The Mediterranean area can expect six more
weeks of heatwave conditions, with wildfire risk also growing. Water worries will be
aggravated as the southern Med loses a fifth of its rainfall, and the tourism industry could
collapse as people move north outside the zones of extreme heat.
Two degrees is also enough to cause the eventual complete melting of the Greenland ice
sheet, which would raise global sea levels by seven metres. Much of the ice-cap disappeared
125,000 years ago, when global temperatures were 1-2C higher than now. Because of the
sheer size of the ice sheet, no one expects this full seven metres to come before the end of
the century, but a top Nasa climate scientist, James Hansen, is warning that the mainstream
projections of sea level rise (of 50cm or so by 2100) could be dangerously conservative. As if
to underline Hansen’s warning, the rate of ice loss from Greenland has tripled since 2004.
This melting will also continue to affect the world’s mountain ranges, and in Peru all the
glaciers will disappear from the Andean peaks that currently supply Lima with water. In
California, the loss of snowpack from the Sierra Nevada – three-quarters of which could
disappear in the two-degree world – will leave cities such as Los Angeles increasingly thirsty
during the summer. Global food supplies, especially in the tropics, will also be affected but
while two degrees of warming will be survivable for most humans, a third of all species alive
today may be driven to extinction as climate change wipes out their habitat.

3ºC
Scientists estimate that we have at best 10 years to bring down global carbon emissions if we
are to stabilise world temperatures within two degrees of their present levels. The impacts of
two degrees warming are bad enough, but far worse is in store if emissions continue to rise.
Most importantly, 3C may be the “tipping point” where global warming could run out of
control, leaving us powerless to intervene as planetary temperatures soar. The centre of this
predicted disaster is the Amazon, where the tropical rainforest, which today extends over
millions of square kilometres, would burn down in a firestorm of epic proportions. Computer
model projections show worsening droughts making Amazonian trees, which have no
evolved resistance to fire, much more susceptible to burning. Once this drying trend passes
a critical threshold, any spark could light the firestorm which destroys almost the entire
rainforest ecosystem. Once the trees have gone, desert will appear and the carbon released
by the forests’ burning will be joined by still more from the world’s soils. This could boost
global temperatures by a further 1.5ºC – tippping us straight into the four-degree world.

Three degrees alone would see increasing areas of the planet being rendered essentially
uninhabitable by drought and heat. In southern Africa, a huge expanse centred on Botswana
could see a remobilisation of old sand dunes, much as is projected to happen earlier in the
US west. This would wipe out agriculture and drive tens of millions of climate refugees out of
the area. The same situation could also occur in Australia, where most of the continent will
now fall outside the belts of regular rainfall.
With extreme weather continuing to bite – hurricanes may increase in power by half a
category above today’s top-level Category Five – world food supplies will be critically
endangered. This could mean hundreds of millions – or even billions – of refugees moving
out from areas of famine and drought in the sub-tropics towards the mid-latitudes. In
Pakistan, for example, food supplies will crash as the waters of the Indus decline to a trickle
because of the melting of the Karakoram glaciers that form the river’s source. Conflicts may
erupt with neighbouring India over water use from dams on Indus tributaries that cross the
border.
In northern Europe and the UK, summer drought will alternate with extreme winter flooding
as torrential rainstorms sweep in from the Atlantic – perhaps bringing storm surge flooding
to vulnerable low-lying coastlines as sea levels continue to rise. Those areas still able to
grow crops and feed themselves, however, may become some of the most valuable real
estate on the planet, besieged by millions of climate refugees from the south.

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