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Scientists Blocking out the Sun
Ashtangiman writes to tell us The New York Times is running an article about geoengineering in which many solutions to global warming include decreasing the amount of sunlight that the planet sees. The ideas are not new, many have been around for quite some time, however they have been relegated to the fringes of science and many have never been published because of this. From the article: "Geoengineering is no magic bullet, Dr. Cicerone said. But done correctly, he added, it will act like an insurance policy if the world one day faces a crisis of overheating, with repercussions like melting icecaps, droughts, famines, rising sea levels and coastal flooding."
How to Cool a Planet (Maybe)
By WILLIAM J. BROAD
In the past few decades, a handful of scientists have come up with big, futuristic ways to fight global warming: Build sunshades in orbit to cool the planet. Tinker with clouds to make them reflect more sunlight back into space. Trick oceans into soaking up more heat-trapping greenhouse gases.
Their proposals were relegated to the fringes of climate science. Few journals would publish them. Few government agencies would pay for feasibility studies. Environmentalists and mainstream scientists said the focus should be on reducing greenhouse gases and preventing global warming in the first place.
But now, in a major reversal, some of the world's most prominent scientists say the proposals deserve a serious look because of growing concerns about global warming.
Worried about a potential planetary crisis, these leaders are calling on governments and scientific groups to study exotic ways to reduce global warming, seeing them as possible fallback positions if the planet eventually needs a dose of emergency cooling.
"We should treat these ideas like any other research and get into the mind-set of taking them seriously," said Ralph J. Cicerone, president of the National Academy of Sciences in Washington.
The plans and proposed studies are part of a controversial field known as geoengineering, which means rearranging the earth's environment on a large scale to suit human needs and promote habitability. Dr. Cicerone, an atmospheric chemist, will detail his arguments in favor of geoengineering studies in the August issue of the journal Climatic Change.
Practicing what he preaches, Dr. Cicerone is also encouraging leading scientists to join the geoengineering fray. In April, at his invitation, Roger P. Angel, a noted astronomer at the University of Arizona, spoke at the academy's annual meeting. Dr. Angel outlined a plan to put into orbit small lenses that would bend sunlight away from earth -- trillions of lenses, he now calculates, each about two feet wide, extraordinarily thin and weighing little more than a butterfly.
In addition, Dr. Cicerone recently joined a bitter dispute over whether a Nobel laureate's geoengineering ideas should be aired, and he helped get them accepted for publication. The laureate, Paul J. Crutzen of the Max Planck Institute for Chemistry in Germany, is a star of atmospheric science who won his Nobel in 1995 for showing how industrial gases damage the earth's ozone shield. His paper newly examines the risks and benefits of trying to cool the planet by injecting sulfur into the stratosphere.
The paper "should not be taken as a license to go out and pollute," Dr. Cicerone said in an interview, emphasizing that most scientists thought curbing greenhouse gases should be the top priority. But he added, "In my opinion, he's written a brilliant paper."
Geoengineering is no magic bullet, Dr. Cicerone said. But done correctly, he added, it will act like an insurance policy if the world one day faces a crisis of overheating, with repercussions like melting icecaps, droughts, famines, rising sea levels and coastal flooding.
"A lot of us have been saying we don't like the idea" of geoengineering, he said. But he added, "We need to think about it" and learn, among other things, how to distinguish sound proposals from ones that are ineffectual or dangerous.
Many scientists still deride geoengineering as an irresponsible dream with more risks and potential bad side effects than benefits; they call its extreme remedies a good reason to redouble efforts at reducing heat-trapping gases like carbon dioxide. And skeptics of human-induced global warming dismiss geoengineering as a costly effort to battle a mirage.
Even so, many analysts say the prominence of its new advocates is giving the field greater visibility and credibility and adding to the likelihood that global leaders may one day consider taking such emergency steps.
"People used to say, 'Shut up, the world isn't read
Planting trees will not change the total amount of carbon currently participating in the carbon cycle. To do that, we'd have to re-sequester it underground, where we got it.
Which is a non-trivial task. Although perhaps less non-trivial than making the sun set...at three PM!
Reality has a conservative bias: it conserves mass, energy, momentum...
> are we contributing to climate change? its just too uncertain to say... possibly. But concidering how much the atmosphere changes its chemical composition from volcaic activity alone, i think its a bit presumptuous to think that our tiny contribution (in comparison to volcanic activity) means jack shit.
Amazingly, thousands of climatologists have the brass to disagree with you.
Sheesh, evil *and* a jerk. -- Jade
Umm...nature's way of "adapting" to environmental effects is that most everything dies off and those species that don't completely die off evolve and take over the niches that were abandoned or newly created. It's not really the best model to emulate. Also seeing as humanity's population center's have historically formed near water(think Manhattan). Moving houses back a mile or two would effectively displace hundreds of millions of people. That also doesn't take into account the other effects of global warming such as disproportionally increased population growth in lower life forms. A rise of a few degrees can halve the breeding cycle of some insects, effectively outpacing the ability of predators to eat them.
From space.com
.05 percent per decade since the late 1970s.
"In what could be the simplest explanation for one component of global warming, a new study shows the Sun's radiation has increased by
The increase would only be significant to Earth's climate if it has been going on for a century or more, said study leader Richard Willson, a Columbia University researcher also affiliated with NASA's Goddard Institute for Space Studies.
The Sun's increasing output has only been monitored with precision since satellite technology allowed necessary observations. Willson is not sure if the trend extends further back in time, but other studies suggest it does."
Note that he doesn't claim that changes in the Sun's energy output have caused most of the observed global warming, just that such changes could explain global warming.
Please alter my pants as fashion dictates.
I recommend reading the Wikipedia article on Global Warming. Once you do, follow the links to other articles such as Global Cooling and Global Warming Controversy. The last article I mentioned has a section Listing supporters of global warming and also detractors. I recently went through the list of detractors and read what their opinions are (there are articles on some of those people on Wikipedia). As it turns out, the people who don't support global warming still claim that the earth is getting hotter: they only debate the percentage of human influence involved.
There's a good week's worth of reading in there, and I am far from finished. But it is quite informative. Really, the only question is when will this become a problem. Because even if you eliminate mankind, the earth is in a warm cycle, and historically, those cycles tend to wipe out major organisms.
According to the University of California, Santa Barbara:
Larry Niven did this in his novel "A World Out of Time" published in 1976. Damned internet generation.
"... they only debate the percentage of human influence involved."
funny enough, 98% of all experts say human influance is a major contributer.
little fact":
Amount of CO2 released annually by volcanos 110 million tons. Amount of C02 released by you puny humans: 10 billion tons.
The Kruger Dunning explains most post on
Approximately 6KWh/m^2/day hit the surface of the earth from the sun. If the surface of the earth is approximately 509,600,000 square kilometers (509,600,000,000,000 m^2) that leaves us with about 3.058x10^15KWh of energy per day that the earth is hit with. Now obviously that energy is released in some fashion as well, given that the global temperature is in relative equilibrium. (Read: We're not all dead because of temperature variances)
Now .05% of 3.058x10^15KWh of energy comes out to be 1.529x10^14KWh per DAY. Now I'm not absolutely positive, but I think thats technically called a shitload of energy.
Humans consume annually about 1.24x10^14KWh of energy, which is on the order of 1 shitload as well, just to put that number in perspective.
What this all comes down to is: Might it not be possible for that incredibly large fusion reactor in the sky that we call the sun to actually have an effect on average temperature of the Earth? I mean, I'm not an environmental scientist, or an astrophysicist, or even terribly well educated, but I can do a bit of math, and it seems daft to discount the sun when it comes to terrestrial temperature changes. To say only .05% is a bit silly, I think.
I don't deny that anthropomorphic global warming may be happening, but to accept that theory at the expense of all others is a little conceited (on the part of humanity, not individually).
NOTE: All the numbers I used came from very quick google searches, and may or may not be accurate.
http://time-proxy.yaga.com/time/archive/printout/0 ,23657,944914,00.html/
Perhaps we should give the scientists a cooling off period before we start messing with climate control?
Trying to engineer our climate doesn't count as adapting, it is as foolhardy as a little kid trying to cool his bedroom in the summer by breaking out his dad's power tools and cutting holes in the walls.
I'm a historian, and I can tell you for a fact that the earth has been much warmer in the past than it is now, and I really do not think that we are responsible for the climate warming that we're observing now. Applying systems theory to the data doesn't work because our instumentation hasn't been good enough for long enough to really tell us much; we could be looking at a perfectly natural rise in temperature that cycles every few thousand years. The astronomers up the hall from me say that the surface of Mars has been increasing in temperature at the same rate as Earth's for as long as we've been able to observe it. They think that our climate is reflecting a cycle going on in the Sun. It could be so. In any case, a warmer climate is nothing new and nothing to worry about as long we can adapt.
No. Global dimming is due to absorption/reflection of the sunlight in the atmosphere (more absorption than reflection). This is increasing due to pollution. The energy still reaches the earth's atmosphere. The purpose of this proposal is to prevent a portion of the energy from hitting the earth, quite a bit different.
-molo
Using your sig line to advertise for friends is lame.
Decimal point error: .05% (0.0005) of 3.058E15 KWh/day is 1.529E12, not 1.529E14 KWh/day. That's still a lot more than the (1.24E14/365 = 3.397E11) KWh/day that humans use, by about a factor of about 4.5.
And speaking of effects on Earth's temperature, if it weren't for greenhouse effect, the average temperature of the Earth would be quite a bit colder (close to freezing) -- and water vapor contributes far more to that greenhouse effect than does CO2. (This is the reason that humid climates are warmer at night than dry climates -- the day's buildup of heat is blocked from radiating back into space by the H2O in the air.)
-- Alastair
" Though the definition of practical is slightly twisted when dealing with $2,000 a barrel (55 gal) synthetic gear lube.
55 gallons is a "drum". A "barrel" of a petroleum (or synthetic equivelent) product is 42 gallons. Just so you know.