Gwynne Dyer is a freelance journalist, columnist, broadcaster and lecturer on international affairs, originally trained as an historian. He has a Ph.D. in Military and Middle Eastern History from the University of London, and has held academic appointments at the Royal Military Academy Sandhurst and Oxford University.
This is from a recent essay by Dr. Dyer called "Planetary Maintenance Engineer":
The fourth assessment of the Intergovernmental Panel on Climate Change says that global temperature rises of between 2 degrees and 4.5 degrees Celsius (3.6 and 8.1 degrees Fahrenheit) are almost inevitable in the course of this century -- but much higher increases of 6 degrees C (10.8 F) or even more cannot be ruled out.The IPCC reports are produced by some 2,000 of the world's leading climate scientists, nominated by their various national governments, and they operate by consensus, so any predictions they make are likely to err on the conservative side. And they say the argument is over: "It is highly likely [greater than 95 percent probability] that the warming observed during the past half century cannot be explained without external forcing [i.e. human activity]." Indeed, the sum of solar and volcanic influences on the system ought to be producing global cooling right now, if it were not for the human factor.
It's already worse than you think, the IPCC reports, because the sulphate particles that pollute the upper atmosphere as a result of human industrial activity are acting as a kind of sunscreen: without them, the average global temperature would already be 0.8 degrees C (1.2 degrees F) higher. And the report goes on to talk about killer heat waves, more and bigger tropical storms, melting glaciers and rising sea levels -- but it doesn't really get into the worst implication of major global heating: mass starvation.
If the global average temperature rises by 4.5 degrees C (8.1 degrees F), shifting rainfall patterns will bring perpetual drought to most of the world's major breadbaskets (the north Indian plain, the Chinese river valleys, the US Midwest, the Nile watershed), and reduce global food production by 25 to 50 percent. If it goes to 6 degrees C (10.8 degrees F), we lose most of our food production worldwide.
The world's six and a half billion people currently produce just about enough food to keep everybody alive (although it is so unevenly shared out that some of us don't stay alive). Any major reduction in food production means mass migrations, war, and mass death. It is getting very serious.
Obviously, the main part of the solution must be to reduce our greenhouse gas emissions and stop destabilising the climate, but we are probably not going to be able to get them down far enough, fast enough, to avoid catastrophe. Short-term technological fixes to keep the worst from happening while we work at getting emissions down would be very welcome, and a variety are now on offer. But they are all controversial.
Bring back nuclear power generation on a huge scale, and stop generating electricity by burning fossil fuels. Fill the upper atmosphere with even more sulphate particles (you could just dose jet fuel with one-half percent sulphur) to thicken the sunscreen effect. Scrub carbon out of the air by windmill-like machines that capture and sequester it. Seed clouds over the ocean with atomised sea-water to make them whiter and more reflective. Float a fleet of tiny aluminium balloons in the upper atmosphere to reflect sunlight or orbit a giant mirror in space between the Earth and the Sun to do the same job.
The purists hate it, and insist that we can do it all by conserving energy and shifting to non-carbon energy sources. In the long run, of course, they are right, but we must survive the short run if we ever hope to see the long run, and that may well require short-term techno-fixes.
I encourage you to read the whole thing.
Tags: nanotechnology nanotech nano science technology ethics weblog blog
Dyer confronts the challenge of geoengineering with mild dread. But why? Why not think of planetary engineering as something fun and interesting--something akin to an adventure? I don't suggest we should jump on the bunny trail and merrily start sequestering carbon out of the atmosphere like circus comedians clumsily pumping gas out of a burping helium balloon. But maybe we can think of it as an engaging puzzle whose solving would mean a lot of learning and yet another validation of our ingenuity.
Posted by: Jonathan Pfeiffer | February 23, 2007 at 10:57 PM
As temperatures increase as a whole tropical storms will decrease because tropical storms are created when warm fronts and cold fronts collide. Also if temperatures increase Ice melts freeing up fresh water. water also evaporates when temperatures increase creating rain.
In the past When this happened the world became temperate with fewer deserts as a result of increased condensation.
If any one remembers eath science in high school the continent of africa used to be lush and green. geological evidence suggests that during this time in history carbon dioxide levels were many times higher than they are today. You all must remember that in history the rise of living species is a direct result of global warming (a naturally occuring cyclic process)and though we are speeding things up a bit the end product is inevitable because we are comming out of an ice age. crops will benifit animals will migrate and interbreed creating new species.
we as humans forget that extinction is necessary for new life forms to develope and we blame ourselves too much for their demise. Evolution and natural selection put us here for a reason just like every other animal on earth and nothing we do or create is unatural or disruptive to the grand design because in essence we are an integral part of that design.
Posted by: matthew durley | February 25, 2007 at 08:43 AM
Unless you've studied the science for a lot longer than I have, your common sense (about green Africa etc.) won't convince me and shouldn't convince anyone else. Two thousand scientists say you're wrong about some of what you've said.
There have been times when the earth's climate worked differently - when the continents were in different positions. Longer ago than the recent ice age cycle.
"Coming out of an ice age" is frequently almost the same as "going back into an ice age." Interglacials have been a lot shorter than glacial periods recently.
A lot of extinctions, or a lot of extreme weather, could make it difficult to keep 6 billion humans alive. We don't have to be altruistic or "green" to care about not disturbing the environment too much.
Chris
Posted by: Chris Phoenix, CRN | February 26, 2007 at 12:41 PM