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Mimi
climber
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Jul 21, 2010 - 11:36pm PT
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I was playing a lot of tennis when Pinatubo went off. The mostly cloudless deep orange sunsets in Baton Rouge lasted all summer as I recall. We'd always look up and check it out. Such a significant eruption and large ash cloud in our time. Reading about the results of all that data and affects on the planet was exciting.
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DrDeeg
Mountain climber
Mammoth Lakes, CA
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Jul 22, 2010 - 01:01am PT
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I don't think the adjustments are chicanery. The Hansen et al. 2007 paper explains why the adjustments were made, and in particular why the surface temperature observations are not necessarily a good indicator of global average temperature. A lot of the extra energy goes into the ocean, and water has a high heat capacity, so a 0.1C change in ocean temperature represents a lot of energy.
The slight warming of the ocean is probably the source of energy for the ice shelf decay. Bob Bindschadler is putting together a project to try to measure the heat exchange between the ice shelf and the underlying ocean. Their initial effort is at McMurdo, where the shelf is only 100-150 m thick. Their goal afterward is Pine Island, where big chunks of the shelf have broken off, but where shelf ice is about 700 m thick.
The issues have recently been discussed in Nature in a short explanation about Enduring Climate Myths (http://www.nature.com/news/2010/100120/full/463284a/box/1.html);: "Climate scientists grapple with real uncertainties, but those who doubt the reality of human-driven global warming usually ignore those issues and, instead, perpetuate a series of claims that do not hold up to scrutiny." Here are the myths. It would be good to address the real uncertainties in this blog, rather than perpetuate the myths. The myths are in bold; each explanation follows the myth. Do we need here to keep repeating the myths?
Climate models can't provide useful information about the real world.
Models can reproduce much of the climate variation over the past millennium, but projections for the future are subject to well-described uncertainties, both in the understanding of climate and in estimates of future economic development. They cannot therefore provide decision-makers with exact information of the rate of future changes, but they can offer useful general information and they unconditionally predict a warmer world.
Global warming stopped ten years ago.
Climate is not weather. The climate is the multi-decade average of the constantly changing state of the atmosphere. Natural variations can cause temperatures to rise and fall from year to year or decade to decade. Although global temperatures did not rise as quickly in the past decade as in previous ones, the most recent decade was the warmest on record.
Temperatures were higher in pre-industrial times.
The consensus of proxy-based reconstructions of pre-industrial climate is that the second half of the twentieth century was probably warmer than any other half-century in more than a millennium. Warmer periods did occur in the more distant past, albeit under different orbital and geological conditions. In any case, warm spells in the past do not disprove human influence on climate today. The cause of any particular climate change needs to be investigated separately.
Temperature records taken in the lower atmosphere indicate that the globe is not warming.
A decade ago, there seemed to be a discrepancy between surface and tropospheric temperatures. But this issue was resolved when long-standing calibration problems with satellite sensors were discovered. Satellite measurements show that the lower atmosphere is warming at a rate consistent with the predictions of climate models.
A few degrees of warming are not a big deal.
In the most recent ice age, the world was only a few degrees cooler on average than it is today. The current rate of warming is in all likelihood unique in the history of humankind. There may be no such thing as an 'optimum' temperature for the planet, but modern human societies are adapted to the weather patterns and sea levels of the past millennia. The rapidity of global warming substantially adds to the problem.
Measured increases in temperature reflect the growth of cities around weather stations rather than global warming.
Climate researchers have taken great care to correct for the impact of urbanization in temperature records by matching data from more-urban stations with data from rural ones. Moreover, some of the largest temperature anomalies on Earth occur in the least populated areas, including around the Arctic and the Antarctic Peninsula. Measurements also show warming of the surface ocean and deeper marine layers.
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Reilly
Mountain climber
The Other Monrovia- CA
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Jul 22, 2010 - 02:26am PT
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So is a physician going to make a diagnosis on a patient based upon one hours worth of illness? Think about it....
He sure as heck better if that hour is when the patient had his heart attack. Better try another analogy.
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Reilly
Mountain climber
The Other Monrovia- CA
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Jul 22, 2010 - 11:20am PT
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Dear "The Chief",
I don't see where I said the planet wouldn't survive even if we don't.
I guess we just have a different opinion of science. Yes, climate change
is a vastly complicated field and accurate predictions are difficult but
the overall science is unimpeachable. That is why it is called science.
I do have a problem with how politicians use or ignore science. You and
me very likely share common ground there.
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dirtbag
climber
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Jul 22, 2010 - 05:14pm PT
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On another note, I saw elsewhere where the climate change bill is dead for this year.
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DrDeeg
Mountain climber
Mammoth Lakes, CA
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Jul 22, 2010 - 11:49pm PT
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Chief,
I don’t mind the name – being a Chief Petty Officer is a responsibility and an honor. But I have a question for you, for Ed, for myself, and for others reading the thread (though sometimes I worry that its authors outnumber the readers).
What would cause you to change your mind, or at least reconsider your position? To kick this off, I will state my positions clearly, will invite agreement or disagreement of any one of them (or the whole set), and will outline the kinds of knowledge that would shake my convictions. In the couple of years before he died earlier this week, Steve Schneider said that he did not like the IPCC’s phrasing of the summary of consensus about climate change. He said that the statement that it is “highly likely” that humans were causing a significant part of the warming was hard to interpret, and he proposed that we adopt the traditional legal language. In criminal law, the standard of guilt is “beyond reasonable doubt.” When you ask an attorney what probability they assign to reasonable doubt, they don’t have an answer and some don’t like the question. But clearly it isn’t 0%, because there are innocent people in jail. In civil cases, the standard is “preponderance of evidence,” for which the associated probability is lower although again an attorney will not want to name a number. Steve thought that the preponderance of evidence supported the conclusions that, along with natural variability, humans were contributing significantly to climate change, and that the consequences were severe enough that we ought to act.
So I agree with Steve Schneider, for the following reasons:
1. The global climate models are based on physical principles (conservation of energy, mass, and momentum; first and second laws of thermodynamics) and on a long research history in a variety of disciplines (radiative transfer, fluid mechanics, material science, etc). Although all the models are based on basic physics and chemistry, they were coded individually, and the fact that they generally agree with one another about temperature is a good sign, and I understand the constraints on modeling precipitation at the global scale. I would reconsider my position if someone were to show a serious error in the models’ science base, which has developed incrementally over centuries, or if there were a significant coding error that existed in all the models.
2. The models show a reasonable agreement with observations, particularly more recent observations and in response to shocks like volcanic eruptions and El Niño events. Although at coarse spatial scale, they show similar patterns to the observations, for example greater warming in the Arctic than in global average. I also point out that the observations themselves are imperfect; they contain measurement errors but more importantly there is no “right” way to spatially interpolate point data. The satellite data provide information everywhere, but their period of record is much shorter. In any event, I would reconsider my position if someone showed a large, consistent error in the comparisons.
3. Because of my confidence in the basic physics, to change my position I would want a plausible, demonstrated mechanism for getting rid of the excess energy from increased absorption of infrared radiation caused by increased CO2 and the concomitant increased water vapor. Lindzen thought he had one in with the Iris Hypothesis (increased sea-surface temperature would decrease tropical upper-tropospheric anvils and thereby leak radiation to space and act as a strong negative feedback in the global climate system), but the data from the TRMM (Tropical Rainfall Mapping Mission) and CERES (Cloud-Earth Radiant Energy System) instruments show that these clouds have much higher albedos and moderately larger infrared fluxes than those assumed by Lindzen. As a result, decreases in these clouds would cause a significant but weak positive feedback to the climate system, instead of providing Lindzen’s strong negative feedback. The Iris Hypothesis was not bad science, but it looks to be incorrect. Moreover, Lindzen himself said he did not quite understand how it worked. If something else convincing were proposed, I would carefully examine it (but the Lindzen-Choi paper seems to have errors and doesn’t use the CERES data).
4. The slight increase in solar radiation in the last 60 years (when the Sun seems to have perked up) seems too small to affect climate to the degree that temperatures have changed. I believe that the solar signal is an add-on to the CO2 signal but not an alternative. I would reconsider my position if someone showed a plausible, demonstrated mechanism for translating this small amount of energy into a big temperature change at the surface.
Anyone want to weigh in? As Edward de Bono said, “If you never change your mind, why have one?”
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DrDeeg
Mountain climber
Mammoth Lakes, CA
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Jul 23, 2010 - 12:06am PT
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Chief - Just a quick comment. Because global warming will cause more evaporation from the ocean, global precipitation must increase (the atmosphere stores, on average, only about one inch of water). And almost all climate scientists agree that the climate models do not represent precipitation well. In contrast to temperatures, the models do not agree with each other about future precipitation. Therefore this result in the Sahel is not surprising.
Once we agree that climate is changing (by humans or by other means) let us indeed address the consequences. But I really would like your answer to my post above yours.
With good wishes.
Edit added after Chief's P.S. above:
Understanding water vapor and clouds is a huge key to the feedback effects. Water vapor is the most important greenhouse gas, a warmer ocean would evaporate more, so anything that causes the ocean to warm would increase atmospheric water vapor and thereby increase the warming. This is an example of a positive feedback (i.e., a change in one direction leads to an additional change in the same direction).
Water vapor is also the source of clouds and thereby the source of precipitation. In comparison to the carbon cycle, the atmospheric part of the water cycle is incredibly dynamic. The atmospheric storage is about one inch; annual global precipitation averages about 40 inches. So the atmospheric water content is recycled 40 times per year, and the average water molecule spends only 9 days there! In contrast, the average CO2 molecule spends 4-5 years between respiration and photosynthesis.
This is why precipitation is so spatially variable (in the summer in the mountains, you can have a huge thunderstorm in one area and be dry only a few miles away), why interannual variability is so large (consider just the variability in the Sierra Nevada snow in the last decade – the range we have seen in 10 years is 80% of what we have seen in 70 years), and why the climate models don’t do precipitation well. There are two things I can confidently say about precipitation in a warmer world: (i) globally there will be more, but some places will be wetter, some drier; (ii) in the mountains the rain-snow transition will move up in elevation.
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WBraun
climber
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Jul 23, 2010 - 01:02am PT
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Ed H -- "it's not the money, it's the mission"
Just enough money for the food and the climb .....
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DrDeeg
Mountain climber
Mammoth Lakes, CA
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Jul 23, 2010 - 01:11am PT
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Chief, I’m not worried about the planet, but I am worried about humanity. Let’s get away from climate change for a bit and point out another example where humans have caused widespread change. What do you think is the most significant invention of the 20th century, for good or ill? The airplane? The computer? The atomic bomb? The answer might well be one most readers of this thread have not heard of: the Haber-Bosch process to synthesize ammonia from atmospheric nitrogen at industrial scales, and then oxidize the ammonia to produce fertilizer. On the plus side, the invention vastly increased agricultural productivity to feed a lot of people, many more than have ridden airplanes or used a computer. On the negative, its overuse has led to hypoxia (lack of oxygen) in coastal waters and a complete transformation of freshwater chemistry worldwide. Almost all high-elevation watersheds used to be nitrogen-limited; now many export nitrogen.
The point is not to start a thread about nitrates, but to point out that though we consider humans puny, they can change the world. Changes in land use are another example. After the Pleistocene and the Holocene has come the Anthropocene.
I am also not worried about the ultimate state of a warmer world, but about getting there. Suppose natural CO2 concentrations over the last few million years had been in the 500-600 ppm range, what would the world look like? There would have been fewer glaciers, Yosemite would not be so spectacular, and sea level would be higher. But I think civilization would still exist. The cradle of agriculture might have been somewhere else, as would the major ports, and the ocean plants and animals would have adapted to a more acidic environment (we keep forgetting in this thread about the ocean acidity as CO2 rises). But the world, its humans, and its ecosystems would be fine.
The problem is the rate of change. As precipitation patterns shift, will people move, will farmers grow different crops? As cities get too hot in the summer more frequently than they do now, will people move to higher latitudes or will we suffer more heat-related deaths? A historical sea level 10 m higher than now would be OK (sorry Florida), but a 1 m rise in sea level in a century outpaces the rate at which we renew infrastructure, and outpaces the rate at which many millions of people in some areas can migrate. Combine those issues with inertia or stubbornness (Should we really rebuild New Orleans in New Orleans? Should we really grow rice in places with chronic water shortages?) and I see a future where adaptation to changes might well be more expensive than mitigating them. For example, it might have been better had we used fertilizer more judiciously.
And don’t forget the ecosystems. Historically, even during periods of rapid climate change that occurred in the transitions from glacial to interglacial, animals could migrate. But in many places, such movement isn’t so easy today because of intervening land use.
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Reilly
Mountain climber
The Other Monrovia- CA
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Jul 23, 2010 - 01:50am PT
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Amazing how humans spend soooooooooo much time worrying about and then trying to control the future. Humans are always trying to control their surroundings.
Isn't that the essence of a well functioning society or, in your parlance, flight deck?
If you don't anticipate problems they're going to bite you.
If changes can be made without bankrupting society that will prevent the
expensive docks of Rotterdam or half the country of Bangladesh from flooding
wouldn't that be a reasonably pro-active course of action? I realize you
don't understand the science and that is fine. I don't really understand
most of it either but I happen to believe the vast majority of these
scientists are good honest people who are doing important work that is
subject to rigorous peer review by other honest people so that you and I
can take some comfort in knowing that 99% of their work is valid. As I
said a couple of pages back the real issues are how this knowledge is going
to be implemented by the politicos. That is where you should be directing your ire.
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DrDeeg
Mountain climber
Mammoth Lakes, CA
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Jul 23, 2010 - 09:04am PT
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My mind will not change as the impulses and insistence of the those that demand that we all succumb to their side/way of thinking.
Chief – You didn’t answer my question. I would not expect you to be convinced by any argument that starts out, “Hey, I am smarter and more knowledgeable on the subject than you are, so . . .” I tell my students the same thing: try not to pay attention to who I am, but to the logic and consistency of my explanations. We study and listen to others, and perhaps pay a bit more attention to people we think are wiser, but in the end we each have to make our own judgment.
So I understand what would not convince you. I am still wondering, what would convince you?
So let me try the question a different way. Suppose we live another 90 years and you, Ed, and I end up in the Big Pine Sanitarium, where Norman Clyde spent his final years (and where I visited him 6-8 weeks before he died in 1972). Most of the time, we try to regale the nurses with stories of how great we were back in the day, but one day one of them dredges up our SuperTopo 2010 postings and asks, “Who was right?”
So, nearly a century later, what would you think? Let’s say that solar radiation outside the atmosphere has stayed between 1364 and 1367 Watts per sq m (as it did between 1880 and the present). I can think of at least two circumstances in which I would think Chief was right:
- CO2 has risen to 550 ppm. The climate models say this should raise temperatures from 2-10C, with a modal value around 4.5C. This has not happened, and average global temperature has changed by less than +2C compared to the 1900-1950 average. Therefore the effect of CO2 on climate was overblown.
- Or
- Nations had decided to act and alternative energy sources are now the norm, CO2 during the century never went above 400 ppm and is now at 350, methane has remained at its 2010 level, yet global temperatures have risen more than 2C. Global warming is happening, but not because of greenhouse gases.
So, can you specify circumstances in which you would say, “Damn Deeg. You were right. Let’s have a drink.”?
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Bob Harrington
climber
Bishop, California
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Jul 23, 2010 - 10:49am PT
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Hey Jeff, thanks for posting such good summaries of the state of the science.
As far as policy goes, it looks like there are some things we can act on, like earlier snowmelt runoff, longer growing seasons, and higher sea levels, but the fact that we don't even know the sign of the change in precipitation is a big problem. The NRDC just came out with a study of likely areas in the conterminous US to suffer water shortages over the next forty years. Pretty interesting, with the conclusion that climate change will exacerbate water shortages in the southwest and Texas. Part of the study necessarily involved down-scaled predictions of precip from GCMs. For California, the prediction is decreased precip in 2030, but an increase in 2050. What's up with that?
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Bob Harrington
climber
Bishop, California
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Jul 23, 2010 - 11:50am PT
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My point is that policy decisions have to be made despite uncertainty, and one of the largest uncertainties in the GCM predictions is how precipitation will change. Jeff already mentioned this. It may be that precip won't change, but that still would spell trouble for water supply, because evapotranspiration is likely to increase.
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Bob Harrington
climber
Bishop, California
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Jul 23, 2010 - 12:33pm PT
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Those are certainly factors, although I wouldn't say we know how and where the population will change with 100% certainty. I'd venture that all important decisions are made with some uncertainty concerning the relevant information, so, with respect to climate change, the argument that we can't take any action until the science is settled is a red herring. Climate change is no different than anything else in that we will have to make decisions with imperfect information.
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dirtbag
climber
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Jul 23, 2010 - 01:05pm PT
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So if I'm understanding The Chief correctly, even if hypothetically, we knew with 100% certainty humans were causing massive climate change that would be dispuptive and deadly in the long run we shouldn't be worry warts and concern ourselves about it.
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dirtbag
climber
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Jul 23, 2010 - 01:32pm PT
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Alrighty, thanks.
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dirtbag
climber
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Jul 23, 2010 - 01:48pm PT
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Well, many wars are fought over resource issues. Adding more frequent and severe droughts to places like the Horn of Africa will not help.
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dirtbag
climber
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Jul 23, 2010 - 02:52pm PT
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"may be" just dead wrong.
And may be not--and likely not.
But I hadn't heard that about the Sahel, which was interesting.
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DrDeeg
Mountain climber
Mammoth Lakes, CA
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Jul 24, 2010 - 12:45pm PT
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My point and opinion is we have a tract record as a species of doing things on hypothetical conjuncture that regardless of intent, most consistently ends up having a negative impact on this planet. In most if not all cases, we conclude that we thought that we knew with certainty what is right for our species and the good of the planet, but it always ends up not being so.
I think the people who are trying to warn about climate change are, in fact, urging us to not do "things . . . regardless of intent." Humanity's addition of CO2 to the atmosphere, from carbon in coal and oil that was stored deep within the Earth millions of years ago, is in fact a grand experiment with potentially troublesome consequences. CO2 levels are already higher than at any time in the part of Earth's history with the continents in about the same position they are now. And we are pushing the levels even higher
The quote from Chief above is in fact an affirmation of the Precautionary Principle: If an action or policy has a suspected risk (with good reason) of causing harm to the environment, the burden of proof that it is not harmful falls on those taking the action. In this case, "those taking the action" are those who oppose efforts to reduce, or at least slow down, greenhouse gas emissions.
Yes, there is uncertainty about what a warmer world will be like, particularly the regional distribution of precipitation and temperature change and behavior of the ice sheets and thereby sea level. But, in support of Chief's point (perhaps implicit), a good argument for reducing greenhouse gas emissions is to reduce uncertainty.
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