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Global Warming

Letters: More global warming facts

Gord, why would I waste my time trying to engage you in a rational discussion of radiative physics when you've shown in every single one of your posts that all you do is argue from ignorance, state mathematical fallacies, and insult people? If you actually want to see how the numbers are derived, there are plenty of sources of information on the Internet...you've even posted some yourself. For example, the derivation of Earth's equilibrium temperature: http://www.uwmc.uw c.edu/geography/10 0/rad-temp.htm ...and the excess greenhouse heating: http://www.uwmc.uw c.edu/geography/10 0/greenhouse_effec t.htm Note that in that second link, they carefully go through the energy balance of each layer (surface, atmosphere, and space) to show how thermodynamics is *not* violated.  (Aug 5, 2009 | post #89)

Global Warming

Arctic CO2 Fueling Fierce Global Warming Cycle

Translation: Get off my lawn, you kids! Ah yes, to be young in the 50s...when the House Committee on Un-American Activities was in full swing, cigarettes were still healthy, and people of color weren't allowed to drink from the same water fountain. http://upload.wiki media.org/wikipedi a/commons/2/21/Is_ this_tomorrow.jpg  (Aug 4, 2009 | post #25)

Global Warming

There are no greenhouse gases

Why do I bother arguing with Gord? Am I a masochist, or do I just get a weird joy out of baiting trollsWell done, Gord. Now, two questions which show why your math is totally useless: Does any real planet have a non-zero albedo? Is any real planet a true black bodyWhich IR radiation? At low concentrations, only very specific wavelengths are absorbed. Increasing the CO2 concentration will widen the wings of its absorption band to cover other wavelengths of IR, making them opaque, tooHow can you even quote that great link while being totally blind to the summary points he lays out? "Without greenhouse gases, we calculated that the surface temperature would be 255 K (0 F), whereas with greenhouse gases we calculated the surface temperature would be 303 K (86 F). Therefore, the blanketing effect of atmospheric greenhouse gases has caused an elevation of the surface temperature" Maybe you should write the page's author and insist he publish Gord's Theorem: "If I mash the calculator with my fist, my equations don't work! Therefore the greenhouse effect is dumbAgain, you get a gold star for awesome improper use of an equation...That equation only works at Earth pressures for low CO2 concentrations. For much higher pressures, collisional broadening greatly expands the width of the IR absorption, and temperature will follow suit. Go read up on the "curve of growth" and the "voigt profile"...it should help demystify some of this absorption confusion you have.  (Aug 4, 2009 | post #788)

Global Warming

There are no greenhouse gases

Umm, what do you mean "get underway again"? Did it ever stop? Just look at global temperatures, courtesy of NASA: http://data.giss.n asa.gov/gistemp/gr aphs/Fig.A2.lrg.gi f That graph starts low to the left and goes high to the rightIf you look at the above graph, it's closer to 1ºC (1.8ºF), but that's actually a pretty big difference in terms of global temperatures. Remember, the last ice age was only 7ºC cooler than current temps. On the other end of things, the Paleocene-Eocene Thermal Maximum was only 5ºC warmer...which was enough for crocodiles to live comfortably in Hudson Bay, CanadaWell, for year-to-year changes El Niño and La Niña have far greater influence in the temperature variance than CO2. This might be the origin of your notion that global warming has slowed down - much ado was made about 2008 being cold, even though it was almost entirely due to a strong La Niña year: http://www.cdc.noa a.gov/people/klaus .wolter/MEI/ts.gif AGW is only seen on decade-to-decade scales. Think of it like using a yo-yo in a slowly ascending elevator. At an given moment, the yo-yo might seem to drop, but over the long haul it continues climbing. Now, add to that a superimposed trend of the Pacific Decadal Oscillation. The number of El Niños events versus La Niñas over a 30-year period also changes. They key here, however, is that it's also periodic - the number of events will repeat, resulting in a zero-sum phenomenon. This is *not* the case with AGW, which just continues slowly climbing. ...or were you originally asking what the effect of increased CO2 has on the frequency of El Niño and La Niña events? If that's the case, I don't think *anyone* knows the answer to that. The only thing we can be certain of is that warmer El Niño waters can dissolve more CO2, while cooler La Niña waters absorb lessIt's not? Again, look at the graph of temperatures - since 1880 there's a very noticeable acceleration. Nonetheless, there will be a lag between CO2 concentrations and temperature - even if we stopped all CO2 emission tomorrow, the atmosphere will continue to heat for another ~100 years to it radiative equilibrium temperature. Due to the pressure and heat capacity of Earth's atmosphere, it has a radiative timescale that's longer than its dynamical timescale (unlike, say, Mars). Using the Newtonian Cooling approximation, the actual lag will be as large as the difference between the current temperature and its radiative equilibrium timescale. This is a first-order differential equation, so if there's a big difference between Earth's final temperature and its current temperature, the lag will be short. If it's a small difference, the lag will be long. Put in other terms, slowly increasing the CO2 over 100 years causes the temperature to slowly follow suit. If instead we had dumped the same amount of CO2 into the atmosphere but in just a single day, the temperature would change much more abruptly.  (Aug 4, 2009 | post #787)

Global Warming

Letters: More global warming facts

Well, let's be clear - I stated that they should understand the science and judge for themselves - not that they should believe it without question. There are still plenty of unknowns in this field - hurricane frequency, cloud feedbacks, albedo feedbacks, etc. - that one *shouldn't* simply accept on faith, lest it becomes more religion than science. The problem I see is that you have posters like, well, Gord, who set up their equations wrong to begin with, come up with the wrong answer, and then assert that therefore the science must be flawed, too.  (Aug 4, 2009 | post #73)

Global Warming

Letters: More global warming facts

Actually, there's quite a few of us ranging from meteorologists in the soil department, fluid mechanics folks in the physics department, planetary scientists in the astronomy department, not to mention all the folks at white sands doing "super-secret government" stuffI can publish to scientific journals all I want about actual data and actual predictions, but only other scientists would read it. This wouldn't be a problem if we were talking about research in some obscure field that isn't politically/econom ically driven, but as it stands Earth climate research has a ton of money pouring into disinformation campaigns for the general public. If people actually understood the AGW science rather than just reading an editorial column in the WSJ bought and paid for by ExxonMobil, they might be able to make a more informed decision about the nature of the science.  (Aug 4, 2009 | post #71)

Global Warming

There are no greenhouse gases

You sound like you're about to have a stroke there, buddy. Take a valium and chill out on the couch for an hour. The 328K reference is right hereYou then go on to babbleYes, let's take a look at that post, shall weSo you use the 735K (measured, not derived) and conclude 407K of warming. Almost right (it's closer to 510K), though you still ascribe an albedo of zero for Venus...if you've ever seen it at night, that tells you right away it's albedo is *not* zeroNow this is the truly laughable part. Just because the percentages are similar does not mean they "have about the same amount of CO2". In fact, Venus has about 10,000 times more CO2 since its atmosphere is about 10,000 times more massive. A 15-micron infrared photon trying to escape from a planet's surface out to space doesn't care what the percentage is...it only sees 10,000 times more absorbers blocking its path.  (Aug 4, 2009 | post #782)

Global Warming

There are no greenhouse gases

So wait, what's the physical mechanism by which planetary mass increases the impact of CO2? The only way an atmosphere "feels" the mass of it's planet is from surface gravity. Venus has ~2 times the surface gravity of Mars, but ~10,000 times the amount of CO2. Which do you really think is going to have a bigger effect on temperature: twice the gravity which indirectly increases pressure by a factor of two, or 10,000 times the number of IR absorbers?  (Aug 4, 2009 | post #781)

Global Warming

There are no greenhouse gases

Wait, did you even read my post? I think you're trying to find the conclusion that you want to believe. My whole point is that on Venus CO2 concentrations *by mass* are ~10,000 times greater than on Mars. Translation: CO2 is a huge player on Venus, not so much on Mars. This results in a 5K increase above equilibrium temperature on Mars, but a 500K increase above equilibrium temperature on Venus. What other conditions would you hypothesize are responsible for this vastly different increase above equilibrium temperature? (Note that distance to the Sun is already taken into account in calculations of equilibrium temperature, so it can't be that.)  (Aug 4, 2009 | post #773)

Global Warming

There are no greenhouse gases

Actual temperature on Venus: 750K Gord's derived temperature using crazy-person math: 328K Keep on truckin', Gord!  (Aug 4, 2009 | post #772)

Global Warming

Letters: More global warming facts

Wow, you're doing quite a disservice to those of us who actually are atmospheric scientists here in Las Cruces. Who are you? LessHypeMoreFact actually did a great job replying to your falsehoods with actual physics, but just to supply some supporting materialSimply wrong. As you can see from this graph of Earth's thermal emission (i.e. actual data): http://lasp.colora do.edu/~bagenal/10 10/graphics/earth_ ir_emission.gif 1) The CO2 IR band is not saturated. Increased CO2 would drive the absorption band deeper. 2) The CO2 IR band is not narrow. It covers a good 4 micron bandwidth (200 cm^-1, for those of us who use actual atmospheric science units) As LessHypeMoreFact mentioned, this is due to pressure broadening. You can clearly see this effect by looking at the tiny emission peak at ~15.5 microns within the wide CO2 absorption band. That tiny peak is a small amount of IR escaping to space emitted from CO2 way up in the stratosphere, which is at much lower pressure. Notice how narrow it is - this would also be the width of IR absorption in the troposphere if CO2 weren't at high pressure thereAgain, wrong. Widening/deepening that CO2 absorption band would cause thermal energy to be displaced to higher wavelengths to maintain planetary energy balance. That displacement would necessitate an increase in temperature in line with blackbody emission. Just take a look at Venus and how massive CO2 concentration affects its temperatureOn the contrary, the fact that the stratosphere is cooling while the troposphere warms indicates that it is precisely CO2 which is responsible. Increased solar heating (the usual culprit deniers conjure up) would warm the stratosphere even more than the troposphere. The actual data indicates it must be IR absorption and re-emission which is causing the hot troposphere/cool stratosphere situation...which is precisely what CO2 doesA common red herring tossed out by deniers. Yes, water vapor is the strongest GHG, however, it is *always* in vapor pressure equilibrium with Earth's temperature due to massive sinks/sources: the oceans. Water vapor always responds to temperature, it does not lead. Thus, increased water vapor is caused by increased temperature. CO2, on the other hand, is *not* in equilibrium. Its sinks (oceans and geological processes) have a much longer timescale...on the order of hundreds of years rather than water vapor's matter of days.  (Aug 4, 2009 | post #67)

Global Warming

There are no greenhouse gases

Fun Facts, the whole point is that they *don't* have comparable levels of CO2...that's why Gord's statement is so funny. Each atmosphere might be 95% CO2 *by volume*, but that's a useless measure since Venus' atmosphere is much, much thicker: 90 bars versus Mars' 6 millibars (Earth's atmosphere is 1 bar). In English units, that means each square inch of Venus' surface has a vertical column of about 1260 pounds of CO2 overlaying it. Each square inch of Mars' surface has a column of only about 1 ounce of CO2 overlaying it. The sheer difference in CO2 quantity produces much, much more saturated IR absorption bands on Venus since there are far more absorbers along an optical path. Furthermore, the greatly increased pressure on Venus introduces pressure line broadening: higher pressure means increased molecular collisions. These collisions induce different dipole moments such that absorption can occur at wavelengths displaced from CO2's usual IR absorption band. So, your answer is that it's all about quantity of CO2 and at what pressure that CO2 resides. The IR absorption band on Venus is not only much deeper due to the numbers of absorbers, but it's also much wider due to pressure.  (Aug 4, 2009 | post #764)

Global Warming

There are no greenhouse gases

Hehe, watching Gord try to do actual math is hilariousWow, I wonder who's doing their math right? Gord, or some guy who's just the head of climate analysis at NCAR? How 'bout this, Gord: try your wrong method of zero albedo out on Venus and see what temperature you get. Oh, try it out on Mars, tooNow that's precious! I haven't had this good of a laugh in a while. Don't tell me, it's because they're both 95% CO2, right? It's like saying an elephant and a mouse are both 70% water, therefore they have the same amount of water...  (Aug 3, 2009 | post #754)

Global Warming

There are no greenhouse gases

...and here's where Gord's calculation parts from realityYup, too bad Earth isn't a blackbody. You go to such great lengths to use accurate temperatures for the Sun, yet completely ignore the Earth's true albedo of 0.36. If the albedo were exactly zero, then Earth would not reflect any sunlight at all...it's a wonder how they'd get all those fancy images of Earth from space.  (Aug 3, 2009 | post #738)

Global Warming

Grayson vote traded to get storm center

Whoa, that is an amazing graph. I'm pretty sure by "lost" they mean "energy not turned into work". For example, note the huge energy percentage lost in transportation - the 4-stroke engine is notoriously inefficient and wastes most energy as heat. Admittedly, getting 100% efficiency is impossible (only a reversible, isentropic, adiabatic process can do this, which by definition won't generate any work), but there are a lot better solutions out there - e.g. the Carnot cycle.  (Jun 30, 2009 | post #166)

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