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bookworm
Social climber
Falls Church, VA
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"One can always hide behind the charge that the experts can't be understood because they use "jargon" but we all face that wall in our educational experience and learn how to overcome it."
didn't make an argument about all experts, just many...others are fairly easy to understand (drdeeg, for example, and this guy: http://www.drroyspencer.com/);
"As it is not my job to do that, especially here, I might not wish to spend the time."
no problem, but why the personal attacks? and why not a serious effort to simplify the jargon so that we nonscientists can understand the issues and, therefore, have geater control over our votes (either for politicians or policy)?
"the ancient Greeks, while making some progress in science"
i'd argue they made quantum leaps in science (http://galileoandeinstein.physics.virginia.edu/lectures/thales.html); especially when you factor in their circumstances...give the greeks everything newton had to work with (by the way, did you know newton believed in alchemy?) and one could argue we might be harnessing the power of cold fusion by now
f, you're the best
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DrDeeg
Mountain climber
Mammoth Lakes, CA
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Corniss Chopper:
The question of auto-regulation is important. In climate, there are both positive and negative feedbacks. Examples of positive feedbacks are: (i) more CO2 -> warming -> more water vapor -> warming; and (ii) less snow and sea ice -> darker surface -> warming -> less snow and sea ice.
So the question is, if you have more water vapor then you might have more clouds. Are clouds a negative or positive feedback? "Both" is the answer. Clouds are bright, thus they reflect more solar radiation, so they cool the Earth. However, clouds also trap and reradiate longwave radiation, hence they warm the Earth. You notice these effects in your mountain travels. Cloudy days are usually colder than clear days, but cloudy nights are warmer than clear nights.
In general, the observations from satellite indicate that the warming effect of clouds is a bit larger than the cooling effect. In other words, "cloud forcing" (as we call it) seems to be slightly positive. But how this effect will play out as CO2 increases from the current values (370 ppm) to much higher values (600+) is a source of uncertainty in climate models. At 600 ppm, global temperatures could be as low as 2 deg C warmer, probably 4-5 deg C warmer, and possibly 10-12 deg C warmer.
As Judy Collins sang, "I've looked at clouds from both sides now."
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onthefence
Boulder climber
Fresno
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i am the right wing nut that helped start this whole debate, and i cannot decide where i stand. i think i'm pretty open-minded on this stuff. you can decide. maybe you guys can help me out. my question is to the last poster...how do they create these "climate models?" How do they make the model? I hear them quoted, but aren't there a whole lot of variables that they have to guess at?
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Ed Bannister
Mountain climber
Riverside, CA
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Scott,
the data is in the photo you posted.
Note the peaks in the bacground and the surrounding topography.
Oversteepened headwalls, U shaped valleys, tarns between peaks, cirques with those cobalt lakes in them,,, all, formed by millenia of ice, that has since melted. News flash, it got warmer, before... long before, Henry Ford, long before the industrial revolution. while i recycle, i recognize man has the tendancy to overestimate himself and his influence, the earth is warming, with, or without our help, until it gets cooler again... has anyone heard of Dynamic equalibrium?
Bill Patzert seems not to have, but his funding is based on manmade global warming. and for that matter, that is how al Gore inc is funded too, he has to pat for that private jet fuel somehow.
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DrDeeg
Mountain climber
Mammoth Lakes, CA
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To onthefence and Alpspitz,
Indeed, we ought to be able to explain past climate variability if we are to be believed when we say the change in atmospheric composition explains a good part of the current warming. First (and I note this in earlier posts), the Ice Ages are related to long-period variations in Earth's orbit, via very regular changes in eccentricity (departure from circular), inclination (the axis wobbles a little), and precession (the time of year when Earth is closest to Sun). The periods are, respectively, 100,000, 41,000, and 22,000 years. They are caused by interactions with gravitational attractions from other planets; if the solar system consisted only of Sun and Earth, our orbit would be more regular.
Like waves in the ocean that travel at different speeds, the different periodicities sometimes reinforce each other and sometimes cause opposite effects. In general though, the Ice Ages started when the orbital effects caused winters to be warmer (more snow) and summers cooler (less melt) in the northern hemisphere. Once extensive glaciation starts, it reinforces itself because the snow/ice surface is more reflective. The northern hemisphere apparently drives the process, because there is a lot more land in the north for the glaciers to spread over.
But the orbital variations occur over very long time periods. The same mechanisms that help explain the timing of the Ice Ages do not explain variability on shorter time scales.
As Ken Boulding said, "All experience is in the past. All decisions are about the future." Because climate can change quickly (and we see evidence of rapid changes in ice cores), and it appears to be changing quickly now, many of us think we ought to prepare for the future rather than just let it happen. And if we can predict future scenarios under varying levels of human-caused CO2 emission, then we can make decisions about whether we ought to reduce emissions. We can also argue that we ought to reduce emissions to reduce uncertainty about the future (we pay money already to reduce uncertainty, for example we buy insurance).
To do so, we have to use models. Sorry. We have just one Earth, so we cannot do a clinical trial (like we do with drugs) and increase CO2 on one Earth and not increase it on the other and see what happens. We can use the past as a guide to some extent, but to examine CO2 levels that we are approaching in the near future, we need to go way way back to a time when the continents were in different positions and therefore ocean circulation was much different.
The models vary in complexity. When I teach this stuff, I usually start with a simple one-dimensional whole Earth radiative balance. The idea is that if Earth is in equilibrium with space, the amount of radiation absorbed equals the amount emitted. The mean radiation from the Sun, at the mean Earth-Sun distance, integrated over the sphere, is about 345 Watts per sq m. About 70% of that is absorbed, and it must be emitted for a steady-state Earth.
When you do that calculation, you get a cold answer, in the neighborhood of 250 deg K (273 deg K is the melting temperature of ice). So why is the answer so cold? The answer is right; that is the radiating temperature of Earth. The reason that Earth's surface is warmer than the radiating temperature is because of atmospheric absorption of the radiation emitted from the surface. If we use a three-layer model, the surface plus two layers in the atmosphere, we get an answer that matches the mean Earth-surface temperature (288 K, same as 15 C).
Then you can incrementally add complexity to the model: variations of solar radiation with latitude, coriolis effect from the rotating Earth, land and water differences, the water-energy cycle (energy used in evaporation, then given back where the water vapor condenses), the effect of differences in reflectivity, soot and dust in the atmosphere and on the snow, feedback effects, etc.
From satellites, we can also make global-scale measurements. We can see the spatial variability of absorption and emission of radiation, for example, and we can compare model results with more precise measurements. We can also use evidence of temperatures in the distant past (for example, ratios between a stable isotope oxygen-18 and the normal oxygen-16) to put together observations that we can test models against.
No climate scientist argues that the models are perfect, but they match observations reasonably well (and we have to recognize that the observations are not perfect either). The models reproduce temperature better than precipitation.
If you want, you can join a climate modeling experiment: http://climateprediction.net. To explore the uncertainty in the models, this experiment runs the models on about a quarter-million PCs around the world, and tweaks the models to explore the effects of our uncertainty about some of the processes. My only warning is that you don't want to do this on your laptop, which is not designed to run continuously. You need something with a fan, that is, a desktop. The model is smart enough to run in the background, and it won't interfere with your lurking on SuperTopo.
To both of you, I would say get off the fence. There is an interesting parallel between the Global Climate Coalition (financed by companies from the oil, coal, and auto industries), which argued against the evidence for climate change, and the tobacco companies in the 1950s, who argued that smoking did not worsen health. The NY Times recently published an article documenting that the industries' own scientists published an internal memo in 1995 that said, "The scientific basis for the Greenhouse Effect ... is well established and cannot be denied." To its credit, Exxon/Mobil pulled out of the Global Climate Coalition a few years ago because their own scientists said the company was taking a policy position that they could not support.
See http://tinyurl.com/db2guv
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onthefence
Boulder climber
Fresno
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Great post. This will take awhile to sift through it. In my superficial understanding, I find it hard to explain a planet that is obviously warming while sunspots are at the bottom of their 11 year cycle (and that bottom seems to be extending longer than normal.) If suspots are a cause of Earth warming which many other facts seem to suggest, then how could we possibly be warming while sunspot activity has dramatically fallen?
Yet, on the other side, the evidence seems fairly clear that CO2 is a lagging indicator for temperature. If this is true, I really wonder how much of a effect CO2 can really have on temperature. I mean, at best it creates a reinforcing feedback mechanism. You could then make the argument that any increase in temperature set off a positive feedback loop in which CO2 increases which increases temps and so on.
Bear with me. I am not going to just get off the fence, but I am really interested in learning this stuff and I will try to do my homework.
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DrDeeg
Mountain climber
Mammoth Lakes, CA
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Judith Lean has a good paper in Physics Today (2005) that explains that solar irradiance variability accounts only for +/- 0.1 deg of temperature variation (from two competing effects, sunspots and faculae) whereas the CO2 warming is about 0.4 deg. We saw minor cooling, order 0.1 deg, from the eruptions of El Chichón in 1982 and Pinatubo in 1991, when the resulting stratospheric aerosols raised Earth's reflectivity a bit.
The CO2 increases that occurred in the warm stages between Ice Ages probably did lag temperature. As the ice melted, more of the biosphere was exposed. In the current warming, however, the extra CO2 is produced by fossil fuels (see an earlier post of mine). They cause warming because they absorb the infrared radiation emitted by Earth's surface. It's good that we have some CO2, otherwise Earth would be a lot colder.
Earth is a complicated system, so it is not surprising that people and companies who want to avoid action can spread confusion. Similarly, others agree that there is a problem but doing anything about it is too expensive. Either of these outlooks guarantees failure. So what are the alternatives? A combination of renewables, energy efficiency, halting deforestation, and (especially) capturing CO2 from coal burning and sequestering it.
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dirtbag
climber
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"Wouldn't fluctuations in planetary orbits proceed over much larger time spans? "
Yeah, that's an objective source.
"Heartland's mission is to discover, develop, and promote free-market solutions to social and economic problems. Such solutions include parental choice in education, choice and personal responsibility in health care, market-based approaches to environmental protection, privatization of public services, and deregulation in areas where property rights and markets do a better job than government bureaucracies."
Give me a break.
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Jennie
Trad climber
Idaho Falls
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May 10, 2009 - 02:32am PT
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Certainly!...take a break anytime, dear Dirtbag. I'm in full sympathy with how NASA findings, about Mars warming, might offend ones "objective" sensibilities.
While you and Al are regrouping, Tipper and I are going to lecture the Martians about parking those gas hogs and getting on their bicycles to counter the alarming rise in their planet's temperature.
(Of couse, as righteous messengers, we won't be called upon to make like sacrifices. We earthly greenies require special dispensation to proclaim inconvenient interplanetary truths to a blind and corrupt solar system.)
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Noaht
climber
Seattle
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May 10, 2009 - 02:02pm PT
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Had a conversation with a skeptic the other day. He kept bringing the conversation around to a politics--socialism vs capitalism. Your missing some larger points, I told him.
I'm of the mind that if you're solely focused on the question of whether or not man is the direct cause for earth's warming trend, your missing a whole slew of important issues--issues that don't seem to have much debate surrounding them, but are equally tied to man's desire to burn of fossil fuels:
Air quality, water quality, deforestation, acidification of the oceans, social justice of indigenous communities, etc.
If there are technologies out there to reduce our impact on these other areas of concern, as a global community lets try not to get hung up on the phrase "global warming," and the surrounding sh#t-storm of controversy it ignites.
Cheers, Noah
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dirtbag
climber
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May 10, 2009 - 02:27pm PT
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"Certainly!...take a break anytime, dear Dirtbag. I'm in full sympathy with how NASA findings, about Mars warming, might offend ones "objective" sensibilities.
While you and Al are regrouping, Tipper and I are going to lecture the Martians about parking those gas hogs and getting on their bicycles to counter the alarming rise in their planet's temperature.
(Of couse, as righteous messengers, we won't be called upon to make like sacrifices. We earthly greenies require special dispensation to proclaim inconvenient interplanetary truths to a blind and corrupt solar system.) "
"Stories" from crap publications, and likely taken out of context, should not be taken seriously. Oh, but I'm sure we are getting the entire story from that right wing axe grinding propaganda piece.
HAHAHAHAHAHAHAHAHAHA. What a joke, except not a funny one.
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Ed Hartouni
Trad climber
Livermore, CA
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May 11, 2009 - 01:49am PT
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I think anyone can get an account Nature on its site http://www.nature.com/
Look up Lori Fenton's article, Nature 446 646 (2007) and read it... it is interesting.
The title is "Global warming and climate forcing by recent albedo changes on Mars"
where "albedo" is the "reflectivity" of Mars to incident radiation. Mars changes its coloration, the dark and light patches absorb differing amounts of solar radiation. They state in the summary paragraph: "Our results suggest that documented albedo changes affect recent climate change and large-scale weather patterns on Mars, and thus albedo variations are a necessary component of future atmospheric and climate studies."
No one I know disagrees.
The central conclusion of the study is that Mars has been getting warmer since the first measurements in the 70s which measured surface temperature. Viking 1 landed on 7/20/76 and operated 6 years 4 months (and was killed by an errant software update). Viking 2 landed on 9/3/76 and operated 3 years 7 months until its battery failed. These two "weather stations" provided data for this relatively short time.
The Viking orbiters provided data from their Infrared Thermal Mapper (IRTM) comparable to the Thermal Emission Spectrometer (TES) data of the Mars Global Surveyor; which entered orbit 9/11/97 and operated for 9 years.
Of course, to make sense of these measurements, as well as the albedo observations possible from earth, a model of the Martian atmosphere is necessary, NASA uses its "Mars General Circulation Model," this is a "climate model" for Mars allowing scientists to study Mars climate.
This is a great paper, in my opinion, and concludes:
"Martian climate indicators, such as GDS [global dust storm] occurrence, polar energy balance, and annual global-mean air temperature, are dependent on many interrelated and poorly understood processes. By investigating solely the effects of changes in surface albedo (from two very different Mars years), we have shown that albedo interacts with, and could in part drive, other climate-influencing processes on Mars."
Oddly, NASA had a mission to measure earth albedo: Deep Space Climate Observatory. It's problem was that it was proposed by Al Gore in 1998, then it was called "Triana"... Congress objected, and requested a National Academy of Science panel to look at it:
"The conferees have not terminated the Triana program as the House had proposed. Instead the conferees direct NASA to suspend all work on the development of the Triana using funds made available by this appropriation until the National Acadcmy of Sciences (NAS) has completed an evaluation of the scientific goals of the Triana mission. The conferees expect the NAS to move expeditiously to complete its evaluation. In the event of a favorable report from the NAS, NASA may not launch Triana prior to January 1, 2001. The conferees have no objection to NASA's reserving funds made available by this appropriation for potential termination costs. The conferees recognize that, if a favorable report is rendered by the NAS, there will be some additional cost resulting from the delay."
Extracted from the NAS study, that you can download: http://www.nap.edu/catalog.php?record_id=9789
From the same letter,
"The scientific themes addressed by Triana are:
 solar radiation and climate, including cloud radiative properties;
ozone, aerosols and ultraviolet radiation;
stratospheric dynamics;
vegetation canopy structure; and,
solar wind and space weather."
Many times I have read in these threads the questions raised by skeptics addressing these very points.
The NAS report was favorable on all accounts:
on the science:
"The task group's assessment of Triana's scientific objectives and goals is based on its review of the relevant literature and presentations regarding the proposed scientific mission. The task group found that (1) the scientific goals and objectives of the Triana mission are consonant with published science strategies and priorities for collection of climate data sets and the need for development of new technologies; (2) if successfully implemented, the planned measurements will likely contribute to Triana's stated goals and objectives; and (3) the Triana mission will complement and enhance data from other missions now in operation or in devellopment because of the unique character of the measurements obtainable at the L1 point in space, which allows continuous imaging of the full sunlit disk of Earth and monitoring of the space environment upstream from Earth."
on the cost:
"...based on the available information, the task group found that (1) the cost of Triana is not out of line for a relatively small mission that explores a new Earth observing perspective and provides unique data; (2) since a significant fraction of the Triana funds (according to NASA and the Triana principal investigator, 50 percent of total funding and 90 percent of instrument development money) have already been expended, weighing cost issues would lead to only limited opportunities to save or transfer funds to other projects."
The satellite was built, but never launched. The Bush administration stated priorities for space were to return humans to the moon and go onto mars. All NASA missions had to justify themselves in terms of accomplishing those goals. Tirana did not, and thus, received no funding and no launch. It sat in a warehouse for 10 years."
Robert Park wrote an OpEd in the NYTimes:
Scorched Earth
By ROBERT L. PARK
Published: January 15, 2006
NASA has quietly terminated the Deep Space Climate Observatory, citing "competing priorities." The news media took little notice. Few Americans, after all, had even heard of the program. But the entire world may come to mourn its passing.
Earth is growing warmer. Even the most strident global-warming deniers have taken to saying that a little warming is a good thing. If the trend continues, however, it will have catastrophic consequences for life on this planet. Correctly identifying the cause could be the most important problem facing humanity.
Most scientists link global warming to unrestrained burning of fossil fuels, which shrouds Earth in a blanket of carbon dioxide, trapping the Sun's energy. Others, backed by industries that spew pollutants into the atmosphere, insist that greenhouse emissions are not the problem. They prefer to attribute warming to natural variations in solar output. Scientists are skeptical, but they don't deny the possibility. The issue cries out to be resolved.
Even in a world wracked by wars, battles are not fought over scientific disagreements. In science, nature is the sole arbiter. Disputes are resolved only by better experiments.
The better experiment when it comes to global warming was to be the climate observatory, situated in space at the neutral-gravity point between the Sun and Earth. Called Lagrange 1, or L1, this point is about one million miles from Earth. At L1, with a view of the full disk of the Sun in one direction, and a full sunlit Earth in the opposite, the observatory could continuously monitor Earth's energy balance. It was given a poetic name, Triana, after Rodrigo de Triana, the sailor aboard Christopher Columbus's ship who first sighted the New World.
Development began in November 1998 and it was ready for launching three years later. The cost was only about $100 million. For comparison, that is only one-thousandth the cost of the International Space Station, which serves no useful purpose.
Before Triana could be launched, however, there was a presidential election. Many of the industries favored by the new Bush White House were not anxious to have the cause of global warming pinned down. The launching was put on hold.
The disdain of the Bush White House for Triana goes much deeper than just a desire to avoid the truth about global warming. Triana began life in early 1998 as a brainchild of Al Gore, who was then the vice president. Mr. Gore, the story goes, woke up one morning wondering if it would be possible to beam a continuous image of the full Earth back from space to inspire people with the need to care for our planet. The 1972 portrait of the full Earth, taken from the Moon, had inspired millions with the fragile beauty of our blue planet. Why not beam the image live into classrooms, allowing students to view weather systems marching around the globe?
Scientists had dreamed of such an observatory for years. They hoped Mr. Gore's influence would make it happen. Mr. Gore's support would end up destroying it. Those who hated him, hated Triana. His dream of inspiring environmentalists and schoolchildren served only to trivialize the project. It was ridiculed as "Gore's screen saver."
Triana is terminated, but global warming is not. Someday, there will have to be an observatory at L1. Perhaps the most important lesson from our exploration of the solar system is that the most terrible place on Earth is a Garden of Eden compared to the best place anywhere else. We must find out how to keep it that way.
Robert L.Park, a professor of physics at the University of Maryland, is the author of "Voodoo Science: The Road From Foolishness to Fraud."
Here is a project that scientists had proposed to help address, scientifically, many of the questions raised regarding the complex atmosphere. Yet, for some reason, this mission was terminated, perhaps for political reasons. So the questions remain unanswered. Not the way to do science, at least not how I learned...
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Jennie
Trad climber
Idaho Falls
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May 11, 2009 - 03:40am PT
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Interesting post, Dr. Ed. Scientific debate seems more effectual abstracted away from the political arena. (I’d rather not consider every issue in the universe in context of right wing/left wing disaccord)
I wonder if opting major politicians (Al Gore) or celebrity activists as primary spokesperson(s) for GW impedes impartial and careful examination of the WHY. Scientists, in my opinion, make much more convincing presentations.
A partisan politician, seeking political purchase, can disaffect a sizable percentage of the population just on the basis of his allegiance, loyalties and personality. The hubris of the favored and famous repels as many as it attracts. Zealous activists yelling, “the global warming debate is over,” can induce a reactive digging in of the heels and a terse “wait a minute.”
Global Warming? I wish I understood all causal factors. But predictive science debate is more palatable when it’s extracted from the political stew.
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dirtbag
climber
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May 11, 2009 - 09:44am PT
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"Global Warming? I wish I understood all causal factors. But predictive science debate is more palatable when it’s extracted from the political stew. "
You say that, but then you extracted an article from a political stewpot journal.
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Chiloe
Trad climber
Lee, NH
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May 11, 2009 - 10:15am PT
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Ed, thanks for the Nature ref, I hadn't seen that article. And a very good detailed post, as usual.
Both Ed and Dirtbag are making key points here, by pointing back to the primary science literature.
*That* is where the torrent of information and well-documented concerns about our changing
atmosphere, oceans and ice is coming from -- not from Al Gore, from "zealots," or other
boogeymen of the right.
All the scientists who've posted here understand this, but I don't think that a single one of
the denialists has got it. For example, most of the major science academies and professional
associations with climate-relevant expertise have adopted resolutions expressing concern
about anthropogenic climate change. These are outfits like the American Geophysical Union,
the American Institute of Physics, the National Academy of Sciences. They aren't politicians,
ideologues, or the minions of Al Gore.
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Jennie
Trad climber
Idaho Falls
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May 11, 2009 - 12:16pm PT
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"You say that, but then you extracted an article from a political stewpot journal."
Hardly, it's neither a political stewpot journal, nor did I extract it.
I offered a link to an article discussing the increase of temperature on Mars and asked, "If true, what natural phenomenon would explain such rapid change?"
You immediately, and without focusing on specific statements, slung sarcasm at it's objectivity (did you read it?),..... and later posted, "Stories" from crap publications, and likely taken out of context, should not be taken seriously. Oh, but I'm sure we are getting the entire story from that right wing axe grinding propaganda piece."
Ed did, in fact, address the Mars temperature issue, with OBJECTIVITY (and without going into right wing/left wing storm mode).....nice there's someone who isn't so politically polarized he can answer a question without insinuating it's beneath consideration.
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stevep
Boulder climber
Salt Lake, UT
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May 11, 2009 - 02:39pm PT
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If nothing else should be obvious from this thread, it's that there are plenty of variables and outcomes that need better definition just when looking at this on Earth. That doesn't mean that there isn't strong agreement around the primary idea of human-caused warming and associated climate change, just that we need to continue to get better about understanding the details.
To use Mars, where we have exponentially less data, understanding, and history, seems utterly ridiculous. Sort of like grabbing at straws.
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DrDeeg
Mountain climber
Mammoth Lakes, CA
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May 11, 2009 - 08:22pm PT
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Thanks Ed. Nice post.
There is an interesting feedback mechanism on Mars. Snow on Mars is mostly composed of CO2, with frozen water a component but not the major one. The Mars atmosphere is almost entirely CO2, with a pressure of about 6 mb, much greater than the partial pressure of CO2 in Earth's atmosphere. The seasonal cycle, at higher latitudes, therefore consists of CO2 "snow" in the winter and sublimation in the spring and summer.
Therefore, when the frozen CO2 sublimates, the CO2 released goes into the Mars atmosphere, where it acts like a greenhouse gas just as on Earth.
The water ice on Mars is typically in the soil.
A couple of Science papers discuss these issues. Perhaps the easiest for the lay reader is David Paige's perspective piece:
http://www.sciencemag.org/cgi/content/summary/sci;294/5549/2107
The main finding is that because of this feedback effect, the climate on Mars has a lot of interannual variability.
You need a subscription (perhaps an institutional one) to Science to read the full article, and the link above references a couple more links.
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