Your right to be sceptical about any specific future claims made by anyone at this point, and about claims being made about the current rise in tempuratures. The truth is that the world is too big with too many variables to model with that kind of precision (weather man anyone?). However, here are the facts. 1. CO2 absorbes more heat from the sun then the standard composition of air. 2. CO2 levels are higher (from us) then they have ever been in any time that we have any data on, and they just keep going up. 3. Eventually, something has to break and earth will begin to heat up. Exactly when, at what concentration, and how much per unit rise in concentration it will heat up is currently not accurately known (I.E. recent revelations about the oceans soaking up more heat than expected, thing like this may keep happening because again there are just too many variables). The phenomenon is real, but sensational statements from the media and scientists involved that can be easily disproven, or called into question have created a distrust about the whole thing. Not to mention the climate gate crap. If they had just stuck to the facts they there could be no argument (cuz there facts you know, not that wouldn't stop some). It is inevitable if we continue on this course. I am quite sure however, that with all the distrust bad shit will have to happen (rising oceans destroying major cities and whatnot) that can be directly linked to global warming before any decisisive action is taken by the world as a whole. One can only hope that by then, it is not too late to do anything about it.
Actually CO2 levels are at historically very low levels, as is the temperature of the Globe. Please Register or Log in to view the hidden image! Or consider this chart. All the time that the temps are running from -2 to -8C (which is by far, MOST of the last half million years) the world is covered in a layer of thick Ice, often reaching down past Chicago, and the levels of the ocean's plummet by up to 120 meters. Please Register or Log in to view the hidden image! Note, while it's not obvious when comparing these two charts, do note that the RISE in global temperature in these charts PRECEEDS the rise in CO2 by roughly 500 years, and the FALL in temps is likewise not prevented by high levels of CO2, but falls after the temp falls. And the world looked like this: Please Register or Log in to view the hidden image!
They, the scientists involved, did just stick to the facts, and nothing they stated has been disproven easily or otherwise. That does not appear to have been enough.
Let's say roads average 20 feet across. That's 4500 square miles of road, or .00225% of the earth's surface. And keep in mind that seawater absorbs more heat than old asphalt (albedos of .08 and .12 respectively) and there's a lot of seawater. Gasoline contains about 36kwhr of thermal energy per gallon. So that's about 127 million kilowatts of heat generated by gasoline burning. Now let's compare that to the forcing by the CO2 that we've added to the atmosphere, which is about 1.6 watts per square meter. The surface of the planet is 510 000 000 sq km or 510 000 000 000 000 sq m. CO2 forcing affects radiated heat, so it affects the entire planet. That's 816 000 000 000 kilowatts of additional heat. To put it another way, the heat generated by burning the fuel is 0.000015% of the heat due to the extra CO2. Well, less obvious when you do the math.
Don't let facts get in the way of a good argument. Please Register or Log in to view the hidden image! Great post.
We had an Ice Age in the past, and there were no industries then to trigger global warming with carbon and other emissions as is claimed by the environmentalists or even by the governments. I strongly believe that our planet has its own reasons for climate change and we humans can't own it entirely with our limited knowledge !!
Strawman hypothesis. The claim that is made is that carbon causes warming,that we're causing the observed increase in atmospheric CO[sub]2[/sub] and that we are, as a direct consequence of this, causing warming in the environment. That greenhouse gasses cause warming is trivially demonstrable. That carbon dioxide is a greenhouse gas is equally trivially demonstrable. The first demonstration uses physics such as greybody and blackbody radiation, combined with the inverse square law and empirical measurements. The second demonstration can be done with simple harmonic motion, is backed up by quantum mechanics, and has been confirmed by empirical measurements. The only question that is then left is what effects this excess heat energy will have on the environment. The claim that "there were no industries then to trigger global warming with carbon and other emissions as is claimed by the environmentalists or even by the governments" is incorrect antiscience disinformation. What is "claimed by the environmentalists" is that previous episodes of climate change were driven by various naturally occuring factors: -Natural variations in atmospheric chemistry: There are a number of ways that atmospheric chemistry can vary naturally. The uplift of the Tibetan and Colorado plateaus, and their subsequent erosion, for example, is thought to be responsible for much of the cooling during the cenozoic. -Variations in Orbital Parameters: These are the milankovich cycles. Variations in elipticity, axial tilt, and so on lead to variations in the amount of insolation, which in turn changes climate forcings, warming or cooling the climate. Contrary to 'popular' opinion, environmentalists do actually believe that the sun drives climate. That's the whole point, in fact. -Variations in Solar output: Contrary to popular belief, solar variability part of climate modeling. -Variations in Geography: Things like equatorial supercontinents, land locked polar seas, and polar continents are all known (from the geological record) to be drivers of long term climate change. Basically, anything that affects the transport of heat energy from the equator to the oceans. For example, the opening of the drake passage and the establishment of the antarctic circumpolar current is one of the factors believed to have contributed to or even accelerated the glaciation of Antarctica.
Trippy/billvon, Excellent posts as usual. I'm not sure I've ever seen either argument put together like this. Very convincing.
What's wrong with this statement? i) It uses the word "historically" without qualifying it. Humans and other mammals are living in a climate which is "historically" low-temperature. ii) It looks like it's suggesting that everything is normal, nothing to worry about. But mammals, and certainly humans, don't have the same history; mammals are adapted to this relatively low-temperature and low-CO2 climate. Then this: Says nothing useful about the RISE in global temperatures being observed today and whether humans are responsible. The charts show natural variations in CO2 and temperature. It isn't true either, that historically temperature always preceded CO2 rises. And it isn't true that when these changes occurred in the past, the planet was dominated by a species that was very efficient at finding and burning fuel, at cutting down trees and making large-scale changes to the environment. And it isn't true that the historical warming mechanisms are fully understood. Nor is it true that the IPCC has all the answers. Since there is a "lot" of uncertainty it just isn't very intelligent to think "nothing much will happen" over the next century. In fact, we don't know enough to say. Proclaiming "the sea won't rise by more than 1 metre in the next 100 years", is really just guessing, I would estimate the uncertainty in that guess to be at least 100%. Note that rising sealevels is only one effect of warming, another is increased levels of H2O in the atmosphere, so more precipitation, more floods, wilder weather because of the increased transport of heat (because of the extra H20). My take is that humans (or some of us) are intelligent enough to understand the "dangers", but also complacent enough to not do anything. It is quite unlikely that we will collectively mitigate warming by drastically reducing our carbon output. We aren't that "intelligent". So the world is going to change, maybe not that noticeably for most people alive today, but then again, there is a large uncertainty. I know, I know, we like to be optimistic; perhaps some new technology will save the planet? Well, "historically", human technology hasn't had a good record there; I can't think of any example that we've been using for any decent amount of time that qualifies as a planet-saver, how about you?
Please Register or Log in to view the hidden image! billy T comment: This black cloud has a silver lining, especially for Russian exports to China. Also self accelerating, it would seem to me to be the great reduction in summer albedo - more sunlight heating with near black water instead of white snow.
Yes. It is mainly a function of the angle of incidence of the photon striking the water surface and that can be much more nearly normal due to waves and even ripples too small for humans to see. Artic regions often have winds so it is much more complex than just a latitude function. The low gross angle of incidence at high latitude means rarely will the photon hit the low point of the ripple (or wave) but mainly hit on the sides of the wave shape. This is the same reason any rough surface has lower albedo than same material with an atomically smooth surface does. Or crudely: rough surfaces are blacker than smooth surfaces for non-normal gross incidence as some of the photons do have near normal incidence on a rough surface. Quite possibly this is why the water in photo of post 850 looks so black.
No, Billy. All the information you need for interpreting that photo is in the photo itself. If you examine the photo carefully: Please Register or Log in to view the hidden image! You will see that the water is, in fact, quite calm. We can infer this from the fact that we can observe specular reflection of the ice cliffs in the background. If we examine the photo closely, we can see that the water is reflecting the colour of the sky almost through the entire photo - almost but not quite, because when the angle subtended to the water by the rays that reach the camera exceeds a certain value, the water is no longer capable of specular reflection, except off, for example, ripples in the surface. The water looks the way it does because the water is reflecting the sky up until the line to the camera reaches some critical angle and the camera can no longer see the reflection.
Yes at least on the scale of the film resolution, Perhaps even on the scale of human resolution, if you were there, but not very likely to be flat on the scale that counts for abledo determination - I.e. free of ripples on the scale of solar radiation wavelengths.
I doubt that the pressure is high enough to form methane hydrates under floating sea ice, except possibly below very large icebergs, but under the Greenland ice sheet, which at points is more than a mile thick, it surely is. As paper has been published by Nature one of the two most important general science journals in the world, their result must be taken seriously. The following is not new, but seems to be gaining support again:
Why are you still trying to argue this point Billy? Nothing in that article contradicts anything that I have actually said, if you've taken the time to understand what I'm saying instead of just reacting to it. Here's what you said: To which I replied: According to peer reviewed and published literature, the albedo of the ocean varies between 0.01 and 0.4, and as well as being dependent on the angle of incidence, is also dependent on wavelength, aerosol optical depth (the effect of which is angle dependent), wind speed, and chlorophyl loading. Snow, on the other hand, has an albedo in the vicinity of 0.8-0.9. So yes, when your albedo drops from 0.9 to 0.4 you're going to get increased warming, and at no stage have I suggested otherwise (nor is it reasonable to infer that suggestion from anything I have said). This, however: Please Register or Log in to view the hidden image! Is not, "Nearly black" (Desert sand has an albedo of 0.4) This, however is: Please Register or Log in to view the hidden image! (Fresh Asphalt has an albedo of 0.01). And yes, I'm aware that there are any number of sources that you will be able to cite that state that the ocean has an albedo of 0.01 to 0.1, however, the figure of 0.4 is empericly measured, but was only published in 2004. And so, I stand by my assertion that your statement "...more sunlight heating with near black water instead of white snow..." is wrong, because the water in the polar regions, due to the low incidence angle, is not properly characterized as "Nearly black", and my statement "You do know that the albedo of water is latitude dependent, right?" Nor anything I have said in that contradicts the assertion that melting in the polar regions will cause warming. Are we clear? Or do you want to keep flogging a dead horse?
No. Your long post is quite enough flogging, especially as in reply to your asking me if I knew about the latitude dependance, I said "Yes" and pointed out that what really matters is the angle of incidence of the light on the water surface and even tiny ripples change that from the gross latitude effect. I.e. even at the North Pole, with waves, some photons are nearly normally incident on the surface and they have very high probability of being absorbed. If, however, the wave are "rolling over" and making "white caps" that can boost the albedo back up. Post 855, was not to argue on what we basically agree on, but just to note that Cambridge Un. prof had just given a convenient quantative comparison (Change to open arctic water is like 20 years of man´s CO2 release.) and clearly stated (as I implied with my comment that there was a "silver lining" for Russian shipping to China) that the arctic would be ice free in the not distant future.
As George Carlin says about global warming.... http://www.youtube.com/watch?v=eGOBm2J4tn0&feature=player_detailpage
If you want to see a major source of natural CO2, look at this video from NASA; Fire and Smoke. It is based on 10 years of collecting fire data world wide from space. [video]http://www.nasa.gov/multimedia/videogallery/index.html?collection_id=72681&media_id=116635311[/video]
