EARTH IN BALANCE: The American Geophysical Union urges reductions of 50 percent or more in greenhouse gas emissions to avoid unpredictable climate change.
Image: NASA
-
The Best Science Writing Online 2012
Showcasing more than fifty of the most provocative, original, and significant online essays from 2011, The Best Science Writing Online 2012 will change the way...
Read More »
The scientists of the American Geophysical Union (AGU) warn that greenhouse gas (GHG) emissions must be slashed in half to keep temperatures from rising 3.6 degrees Fahrenheit (2 degrees Celsius)—or else. "Warming greater than 2 degrees Celsius above 19th-century levels is projected to be disruptive, reducing global agricultural productivity, causing widespread loss of biodiversity and—if sustained over centuries—melting much of the Greenland ice sheet with ensuing rise in sea levels of several meters," the AGU declares in its first statement in four years on "Human Impacts on Climate."
The statement, released today, is the latest—and strongest—statement from the Washington, D.C.–based scientific organization on human-induced climate change. "The record of the Earth's climate since the invention of the thermometer is much better understood now," says physicist Tim Killeen, AGU president and director of the National Center for Atmospheric Research (NCAR) in Boulder, Colo. "This detailed understanding of the climate of the 20th century gives confidence in the ability to project into the future. It is now agreed that we can't explain the detailed temperature record of the 20th century without bringing to bear human effects and GHG emissions. That, in a way, is the smoking gun, the fingerprint."
That fingerprint is now clearly visible on Earth's climate, according to physicist Michael Prather of the University of California, Irvine, who chaired the AGU committee that wrote the statement. Humanity's touch has tipped the scales in favor of more of the sun's heat being trapped by the sky and sea. "Earth's energy system is out [of] balance, excess heat is being pumped into the ocean," Prather says. "That means we're on the move to someplace different."
"Someplace different" will be a lot warmer; 11 of the past 12 years were warmer than any since 1850, and 2007 tied 1998 as the second-warmest since instrument-based records began, according to NASA. Global average sea level has risen by roughly 0.11 inch (3 millimeters) per year since 1993 due to a combination of water expanding as it warms and melting ice sheets. "The scales of change we are seeing is something that modern society has never experienced," Prather notes.
But cutting global (GHG) emissions by 50 percent by 2050 is a major challenge that would require curbs on the smokestacks of power generators and the tailpipes of vehicles as well as a halt to deforestation, among other efforts. Although California, the European Union (E.U.) and others have pledged to meet that goal, global emissions continue to climb rapidly—as do concentrations of GHGs in the atmosphere. "We're on a trajectory upwards for the next five or 10 years no matter what we do. We need to turn that over and bring it down," Prather says. "What we're really looking for is much more substantial cuts by the end of the century."
Regional emission efforts—such as the E.U.'s new plan to reduce emissions by 20 percent by 2030—are already underway. Most rely on so-called cap-and-trade mechanisms: an overall cap on emissions is set, allowances to meet that cap are distributed to polluters, and those who emit more or less than their quota can buy or sell these allowances. Killeen notes that those programs will rely on unprecedented precision in measuring and monitoring greenhouse gas emissions, a role AGU scientists might fill.
See what we're tweeting about
14 Comments
Add CommentMakes me glad that I escaped from the academic world. If the AGU can be so dense as to believe we control the environment, then they ought to be locked away in their ivory towers so they can't tax us to death.
Reply | Report Abuse | Link to thisHello,
"Makes me glad that I escaped from the academic world."
So am I. Anyone who rejects the vast amount of evidence for Global Warming does not deserve to be in academia.
--
Edited by Trent1492 at 01/25/2008 7:52 AM Reply | Report Abuse | Link to this
You folks should learn to be skeptical. Please read this essay.
Reply | Report Abuse | Link to thishttp://www.crichton-official.com/speech-ourenvironmentalfuture.html
This is simply impossible because Rush Limbaugh and Michael Savage say so.
Reply | Report Abuse | Link to thisHere is the link again.
Reply | Report Abuse | Link to thishttp://www.crichton-official.com/speech-ourenvironmentalfuture.html
I wonder if it will get wiped out again.
so instead of hundreds of top climate scientists, you believe......errr... crichton? the fantasy fiction writer????
(not even decent science fiction)
the guy that was debunked here?
http://www.skepticalscience.com/broken-hockey-stick.htm
and here?
http://www.realclimate.org/index.php?p=74try this link instead people!
http://www.realclimate.org/
-- Edited by u.k.gerda at 01/26/2008 12:59 PM -- Edited by u.k.gerda at 01/26/2008 12:59 PM--
Edited by u.k.gerda at 01/26/2008 1:02 PM Reply | Report Abuse | Link to this
SciAm has been politically biased for many years. Remember their scare articles in the 60's about nuclear arms, and in the 70's about famine, and their ridiculous attampts at economic theory, etc. This led me to abandon my 30 year subscription in 1996. Global warming is simply the new front in their leftist propaganda undercurrent. Unfortunately Discover is not much better. Where can one get science articles for the educated (PhD) scientist who wants to keep up on a wide range of fields without being inundated with BS?
Reply | Report Abuse | Link to thisHello Bigter,
"SciAm has been politically biased for many years."
Yes, we are all aware that truth has a liberal bias.
"Remember their scare articles in the 60's about nuclear arms "
I am to young to have that memory; but I can only imagine the chutzpah it takes to object to vastly powerful weapons owned by mutually antagonistic powers. I mean we all know thermonuclear weapons are our friends.
"... and ..about famine,.."
All those little Third World people starving. I mean who cares, right? After all if a loving God will allow a small children to starve too death; why should their fellow man care?
".. their ridiculous attampts at economic theory,..."
You are so right. It is a proven fact that no one has ever improved upon Adam Smith, EVER.
"This led me to abandon my 30 year subscription in 1996."
I can see your point there has got to be cheaper fire starter.
"Global warming is simply the new front in their leftist propaganda undercurrent. Unfortunately Discover is not much better."
I understand your outrage. How dare those science journalist report the findings of scientist when they could simply print the latest bulletin from Exxon-Mobil.
"Where can one get science articles for the educated (PhD) scientist who > wants to keep up on a wide range of fields without being inundated with BS?"
The National Inquirer may be the journal of record you are looking for.
Yours Trent
Reply | Report Abuse | Link to thisScare articles in the 1960 decade about nuclear arms? Try the November 2007 issue - where they rail against modernizing our nuclear arsenal. Plus while we are on the subject of their politically driven alarmism peruse the back issues - some time towards the end of the 1990 decade I am sure I read an article predicting that by 2000 world oil production would peak, known reserves would be rapidly depleting and there would be war over what oil remained. Well Iran is sure trying to bring that last bit true but other than that from what I understand the only reason we may face shortages is continual failure to look for oil in places like ANWAR and off our coasts where there are most likely deposits that would go a long way towards making the U.S. more energy independent - but unfortunately there are those who prefer us to be dependent, weak, vulnerable. I already made three comments about what a scam anthropogenic warming theories are in another thread so I will just sum up here by pointing out that as carbon dioxide continued to rise, particularly in 2001 to 2003 when atmospheric measurements spiked significantly, temperatures have at best levelled off since 1998 and in fact seem to have most likely declined. The oceans are undeniably cooling and remember just 10 years ago when warming oceans were a "sure sign" of catastrophic anthropogenic warming? So now the same alarmists have to admit we face catastrophic global cooling, right? To be fair and consistent?
Trent1492 says: "Anyone who rejects the vast amount of evidence for Global Warming does not deserve to be in academia."
Actually, anyone who rejects the fact anthropogenic warming is a hoax that exists only in "scenarios" and flawed "models" and who is too foolish to look outside and see that climate is driven by nature, not man, definitely needs to be banned from being near anyone who is impressionable.
Apparently one foot consumed was not enough for Trent1492 as his next post, aside from proving he does not know the difference between "to" and "too", contained several gems (his statement in quotes followed by my comments):
"Yes, we are all aware that truth has a liberal bias."
AHA! Now we know what's wrong with faux liberal thought processes - they think they know truth even as Al Gore openly admits he is lying to them to motivate them AND THEY SAY "THANK YOU SIR, MAY WE HAVE ANOTHER" EACH TIME!
"I am to young to have that memory [of 1960s SciAm scare articles about nukes]; but I can only imagine the chutzpah it takes to object to vastly powerful weapons owned by mutually antagonistic powers. I mean we all know thermonuclear weapons are our friends."
We just made it through what, 60 years of MUTUALLY ASSURED DESTRUCTION, a concept that I, too, initially thought was insane. It worked, go figure. Now with North Korea an announced (if not yet proven) nuclear power and Iran racing to join the club it is the WORST time to be considering NOT updating and verifying our own nukes, as much as I would prefer a world with none. Trent1492 and others like him exist in a fantasy world folks - a world that yeah, I agree would be great IF IT EXISTED. it does not.
"All those little Third World people starving. I mean who cares, right? After all if a loving God will allow a small children to starve too death; why should their fellow man care?"
One has to wonder if this is deliberate sarcasm or an ironic display of Trent1492 as he really thinks. For wasting billions on anthropogenic global warming scams to stop unstoppable natural forces will ensure we do not have the resources to combat poverty and starvation.
"You are so right. It is a proven fact that no one has ever improved upon Adam Smith, EVER."
Another example of idiotic sarcasm or possibly what Trent1492 really thinks. After all he no doubt believes we need universal government run health care - despite the fact it fails everywhere it is tried with the possible exception of small, stable, homogenous populations.
"I can see your point there has got to be cheaper fire starter. [regarding dropping Sci-Am subscription]"
So that is what Trent1492 thinks of Sci-Am - KINDLING! Actually, given the amount of political content and the steady reduction of real science (for an example see the recent story regarding the "rewilding" of the United States) Trent1492 is right - Scientific American is becoming fit for use as kindling more than anything else these days. Hey, that would cause more global warming, would it not?
"I understand your outrage. How dare those science journalist report the findings of scientist when they could simply print the latest bulletin from Exxon-Mobil."
Ah, now we see - Trent1492 is one of those who presents the "argument is over/science is settled/consensus" arguments as "proof" that indeed global warming is 100% anthropogenic and we can actually stop climate change if only we have the will to go back to being cave men with average life expectancies of 25-30 or so.
Tell you what, Trent, YOU GO FIRST, let the rest of us know how it works out for you, OK?
"The National Inquirer may be the journal of record you are looking for."
After all it's where Trent1492 gets all his hard news...
U.K.Gerda says:
"so instead of hundreds of top climate scientists, you believe......errr... crichton? the fantasy fiction writer???? "
First, I always hear about the "consensus" and chuckle when I remember that past consensus said that the Earth was flat, that the Earth was the center of the universe and that all matter was made of only four things - earth, air, fire and water. The consensus argument is the refuge of those who know they have no real arguments to offer. Besides, you need to google (or yahoo or whatever) "PETITION PROJECT" and do a little catching up - hundreds of top scientists in climate and climate related fields, actually THOUSANDS, say that catastrophic anthropogenic warming theories are wrong.
But really we don't even need to go there because you're taking the word of Al Gore, essentially a country bumpkin, over the word of a real DOCTOR (not an honorary one like Gore) who actually made something of his life instead (like Gore) of sucking on silver spoons since birth. You dare to criticize those who actually know what they are talking about and try to bring you truth as you believe Gore, who openly tells you he is deliberately lying to you to try and motivate you? Clearly the right is right - "liberalism" is a mental illness. I put that in quotes because true liberals, true progressives are surely spinning in their graves over what those who've co-opted the terms are saying and doing these days.
--
Edited by Greg001 at 01/27/2008 1:19 AM Reply | Report Abuse | Link to this
According to the link given in the article "human impacts on climate" the temperature has declined since 1850. If you let me chose the point to measure "from and to" in a series of numbers I can prove anything. The main culprit in global warming is the sun. Why not just create a volcano to lower the average temperature?
Reply | Report Abuse | Link to this"But really we don't even need to go there because you're taking the word of Al Gore"
excuse me? you talking to me? typical trolling rudeness.
i have been following the increasingly desparate attemps of climate scientists to bring the problem of anthropogenic climate chang to the attention of the politicians and public for over 15 years! how dare you assume i have been influenced by a politician. mind, you some politicians did pay attention; our margret thatcher took this seriously in the early 1990's, but since then the interests of the oil men have held sway. see hansen's article on the suppression and intimidation of climate scientists by the bush administration.
Reply | Report Abuse | Link to thisMore global warming scare. It would be nice it Scientific American would be more factual and less political. Theoretically, human industry is increasing temperatures. Factually, we have not made a definitive difference. But politics and business as it may be, let's keep scaring people so that donations keep pouring in. "Environmental" groups are as much of a big business as industry. Both will lie and distort facts to keep the bucks rolling in.
Reply | Report Abuse | Link to thisHow can so many commenters be so naive to think that facts are political. What will you say when it's too late?
Reply | Report Abuse | Link to thisActually it is already too late, Global Warming is over!
Reply | Report Abuse | Link to thisHuman caused Global Cooling is the new thing. Hurry up and get on the new band wagon. If you start now you can be right for the next 30 to 50 years.