Climate Science Glossary

Term Lookup

Enter a term in the search box to find its definition.

Settings

Use the controls in the far right panel to increase or decrease the number of terms automatically displayed (or to completely turn that feature off).

Term Lookup

Settings

All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

Home Arguments Software Resources Comments The Consensus Project Translations About Support

Bluesky Facebook LinkedIn Mastodon MeWe

Twitter YouTube RSS Posts RSS Comments Email Subscribe


Climate's changed before
It's the sun
It's not bad
There is no consensus
It's cooling
Models are unreliable
Temp record is unreliable
Animals and plants can adapt
It hasn't warmed since 1998
Antarctica is gaining ice
View All Arguments...



Username
Password
New? Register here
Forgot your password?

Latest Posts

Archives

CO2 is not the only driver of climate

Posted on 25 October 2009 by John Cook

Climate scientists tend to go on a bit about CO2. However, as readers often point out, CO2 is not the only driver of climate. There are a myriad of other radiative forcings that affect the planet's energy imbalance. Volcanoes, solar variations, clouds, methane, aerosols - these all change the way energy enters and/or leaves our climate. So why the focus on CO2? Is it because scientists are all hysterical treehuggers determined to run peoples' lives with a one world government? Or is there a rational, scientific reason for this CO2 preoccupation? Let's find out which...

When I first started investigating global warming science, I attempted to discern the cause by a process of elimination. I studied all possible causes and ruled out any that couldn't be causing all the warming. As my understanding grew, I came to realise this was an inappropriate approach. Understanding what drives climate does not occur by a process of elimination. It's happens by a process of integration. There are many influences of climate and they all need to be considered together to gain the full picture.

For clarity, let me note a few definitions. Radiative forcing is loosely defined as the change in net energy flow at the top of the atmosphere. In this post, we're talking about the radiative forcing from 1750 to 2005. Values are taken from Chapter 2 of the IPCC AR4 which in turn took all their values from peer reviewed papers - apologies that I was too lazy to cite all the original sources. Positive radiative forcing has a warming effect (so obviously, negative radiative forcing has a cooling effect).

  • Surface Albedo has changed due to activity such as deforestation. This increases the Earth's albedo - the planet's surface is more reflective. Consequently, more sunlight is reflected directly back into space, giving a cooling effect of -0.2 Wm-2.
  • Ozone affects the climate in two ways. The depletion of stratospheric ozone is estimated to have had a cooling effect of -0.05 Wm-2. Increasing tropospheric ozone has had a warming effect of +0.35 Wm-2.
  • Solar variations affect climate in various ways. The change in incoming Total Solar Irradiance (TSI) has a direct radiative forcing. There is an indirect effect from UV light which modifies the stratosphere. The radiative forcing from solar variations since pre-industrial times is estimated at +0.12 Wm-2. Note that the radiative forcing from solar variations may be amplified by a possible link between galactic cosmic rays and clouds. However, considering the sun has shown a slight cooling trend over the last 30 years, an amplified forcing from solar variations would mean a greater cooling effect on global temperatures during the modern warming trend over the last 35 years.
  • Volcanoes send sulfate aerosols into the stratosphere. These reflect sunlight, cooling the earth. A strong volcanic eruption can have a radiative forcing effect of up to -3 Wm-2. However, the effect of volcanic activity is transitory - over several years, the aerosols wash out of the atmosphere and any long term forcing is removed.
  • Aerosols have two effects on climate. They have a direct cooling effect by reflecting sunlight - this is calculated from observations to be -0.5 Wm-2. They also have an indirect effect by affecting the formation of clouds which in turn affect the Earth's albedo. The trend in cloud cover is one of increasing albedo which means a cooling effect of -0.7 Wm-2.
  • Stratospheric Water Vapour has increased due to oxidation of methane and had a slight warming effect of +0.07 Wm-2.
  • Linear Contrails from aviation have a slight warming effect of +0.01 Wm-2.
  • Nitrous Oxide reached a concentration of 319ppb in 2005. As a greenhouse gas, this contributes warming of  +0.16 Wm-2.
  • Halocarbons (eg - CFC's) were used extensively in refrigeration and other industrial processes before they were found to cause stratospheric ozone depletion. As a greenhouse gas, they cause warming of +0.337 Wm-2.
  • Methane is actually a more potent greenhouse gas than CO2. Pre-industrial methane levels, determined from ice core measurements, were around 715 parts per billion (ppb). Currently methane rates are at 1774 ppb (eg - 1.774 parts per million). The radiative forcing from methane is +0.48 Wm-2.
  • CO2 levels have increased from around 280 parts per million (ppm) in pre-industrial times to 384 ppm in 2009. The radiative forcing from CO2 is +1.66 Wm-2. CO2 forcing is also increasing at a rate greater than any decade since 1750.

Here's a visual summary of the various radiative forcings:


Figure 1: Global mean radiative. Anthropogenic RFs and the natural direct solar RF are shown. (IPCC AR4 Figure 2.20a)

Putting it all together, Figure 2 compares the warming from human caused greenhouse gases to the total radiative forcing from all human sources.


Figure 2: Probability distribution functions (PDFs) from combining anthropogenic radiative forcings. Three cases are shown: the total of all anthropogenic radiative forcings (block filled red curve); Long-lived greenhouse gases and ozone radiative forcings (dashed red curve); and aerosol direct and cloud albedo radiative forcings (dashed blue curve). Surface albedo, contrails and stratospheric water vapour RFs are included in the total curve but not in the others. Natural radiative forcings (solar and volcanic) are not included in these three PDFs. (IPCC AR4 Figure 2.20b)

Greenhouse gases and ozone contribute warming of +2.9 Wm-2. The majority of this is from CO2 (+1.66 Wm-2). This warming is offset by anthropogenic aerosols, reducing the total human caused warming to 1.6 Wm-2. So surprisingly, the warming from CO2 actually exceeds the final total radiative forcing. If ever asked how much CO2 contributes to global warming, you could say "all of it... and some!" But a more appropriate response would be to list the various contributors of forcing, both negative and positive, although this may cause the questioner's eyes to glaze over (and wish they'd never asked). Framing science is never easy.

The other important point to glean from Figure 2 is that we have a relatively high understanding of greenhouse gas radiative forcing. The probability density function (PDF) shows a much higher probability than the aerosols PDF, meaning the uncertainty associated with greenhouse gas forcing is much lower. This degree of confidence is also confirmed by experimental observations from both satellites and surface measurements which confirm the degree of enhanced greenhouse effect from rising greenhouse gases.

So bringing it all together, there are two reasons for the focus on CO2:

  1. CO2 is the most dominant radiative forcing
  2. CO2 radiative forcing is increasing faster than any other forcing

UPDATE: just read an interview with climate scientist Ken Caldeira which focuses on the issue of geoengineering. But one particular quote summed up the issues discussed above:

Question: They also write that you are convinced that human activity is responsible for “some” global warming. What does that mean?

Caldeira: I don’t think we can say with certainty whether we’re responsible for 90 percent of it or we might be responsible for 110 percent of it. But the vast majority of global warming, I believe, is due to human release of greenhouse gases to the atmosphere.

0 0

Printable Version  |  Link to this page

Comments

Prev  1  2  3  4  5  6  Next

Comments 51 to 100 out of 252:

  1. Chris - re:your post#49 Funny that you use phrases like this: - "pseudophysics approach combined with false logic" What "pseudophysics" and What "false logic" ??? I am the one providing BACK-UP Links to the Physics to support everything I say. You just provide your "OPINIONS" ! Face the FACTS: - You have not produced ANY argument for my posts based on any Physics! - ALL your posts are just your "opinions" with ZERO Back-up. HAHAHA...you are hilarious!
    0 0
  2. Steve - re: your Post #50 The Blanket analogy is false: Do Greenhouse Gases Act As Blankets? http://atmoz.org/blog/2007/08/08/do-greenhouse-gases-act-as-blankets/ Further, right from an on-line AGW Physics textbook... Fundamentals of atmospheric radiation By Craig F. Bohren, Eugene Edmund Clothiaux "....This is yet another reason why assertions about "atmosphere acting like a blanket" are absurd" http://tinyurl.com/lp483t
    0 0
  3. Does anybody here understand any Physics? Take the time to go through my posts, and make a reasonable argument based on FACTS and PHYSICS. Opinions are just "ranting". I will be back later.
    0 0
  4. "If you treat the Earth as a sphere for the Solar Flux you get this equation:" Gord, respectfully, you're **way** off base. The amount of light shining on a sphere is exactly the same as if there were a disk continually facing the light source(if you take a photograph of a sphere it will always look like a disk). Your equation might make sense if there was no such thing as nighttime on any part of the Earth, though. Cheers, :)
    0 0
  5. re #52, Not really Gord. We've already seen that your two fundamental assertions are based on false logic: 1. The greenhouse effect doesn't violate the 2nd law, since the suppression of radiative dissipation of thermal energy from the surface by back radiation from a cooler atmosphere, doesn't require (as you assert) a flow of heat from a colder (atmosphere) to a warmer body (the surface). However much you attempt to dress it up with false logic, your "argument" fundamentslly fails since it's based on a semantic confusion of heat and radiation. 2. The accumulation of thermal energy in the earth system under a positive radiative imbalance obviously doesn't require the "creation of energy". Your non-sequiter ("the sun is the ONLY energy source"...therefore increased thermal energy in the climate system under radiative imbalance is "a violation of The Law of Conservation of Energy") is just silly...it's equivalent to asserting that the analogy of water flowing through a reservoir under constrained outflow (my posts #41 and #43) requires "creation of mass", when nothing is being "created"; the thermal energy (or water) is simply accumulating.
    0 0
  6. Gord, I didn't insist that the atmosphere acted just like a blanket; I said the fact that colder blankets can help you stay warm stomps on the simplistic idea that the Sun is the only factor governing temperature. You didn't take the time to follow the link the I supplied indicating that I'm not saying "the atmosphere is a blanket". And apparently you didn't bother to read the rest of the textbook or Atmoz's blogs to see why the greenhouse effect is real, despite being poorly named and despite the 2nd Law of Thermodynamics. By the way, how are your calculations coming for explaining the relative surface temperatures of Mercury, Venus, and Earth? And come to think of it, here's another thing for you to explain: http://skepticalscience.com/How-do-we-know-CO2-is-causing-warming.html
    0 0
  7. "So bringing it all together, there are two reasons for the focus on CO2: 1. CO2 is the most dominant radiative forcing 2. CO2 radiative forcing is increasing faster than any other forcing" Wouldn't a third reason be the atmospheric life of CO2 compared with say, methane? A little more than a decade for methane. A few centuries for CO2 at least, or perhaps tens of milleniums for a portion of it, according to other studies... http://www.springerlink.com/content/t1265r6548477378/
    0 0
    Response: Good point and thanks for the link. Of course, there are other reasons for the focus on CO2, not the least being we're the ones causing the CO2 rise and unless we stop CO2 emissions, the radiative forcing will only increase. But I've learned through experience to keep the "take home points" from each post down to just one or two concise points. Trying to say too much reduces the impact of the message.
  8. Chris - re:your post #55 You said... "1. The greenhouse effect doesn't violate the 2nd law, since the suppression of radiative dissipation of thermal energy from the surface by back radiation from a cooler atmosphere, doesn't require (as you assert) a flow of heat from a colder (atmosphere) to a warmer body (the surface)." First, there is no "suppression" of radiated energy from the Earth by the Atmosphere. The Radiation occurs at the speed of light and ALL the Earth's Radiation (390 w/m^2) is radiated to cold space....without "suppression"! ------ Second, the "Greenhouse Effect" links say EXACTLY THE OPPOSITE OF YOUR RANT ! Tutorial on the Greenhouse Effect- University of Arizona “In this case, the Earth still gains 240 Watts/meter2 from the sun. It still loses 240 Watts/meter2 to space. However, because the atmosphere is opaque to infrared light, the surface cannot radiate directly to space as it can on a planet without greenhouse gases. Instead, this radiation to space comes from the atmosphere. However, atmospheres radiate both up and down (just like a fire radiates heat in all directions). So although the atmosphere radiates 240 Watts/meter2 to space, it also radiates 240 Watts/meter2 toward the ground! Therefore, the surface receives more energy than it would without an atmosphere: it gets 240 Watts/meter2 from sunlight and it gets another 240 Watts/meter2 from the atmosphere — for a total of 480 Watts/meter2 in this simple model.” http://www.lpl.arizona.edu/~showman/greenhouse.html The Greenhouse Effect “Absorption of longwave radiation by the atmosphere causes additional heat energy to be added to the Earth’s atmospheric system. The now warmer atmospheric greenhouse gas molecules begin radiating longwave energy in all directions. Over 90% of this emission of longwave energy is directed back to the Earth’s surface where it once again is absorbed by the surface. The heating of the ground by the longwave radiation causes the ground surface to once again radiate, repeating the cycle described above, again and again, until no more longwave is available for absorption.” http://www.physicalgeography.net/fundamentals/7h.html Both examples violate the 2nd Law because there is heat energy flowing from a colder atmosphere to a warmer Earth. The above Greenhouse Effect links describe a Perpetual Motion Machine, actually a Perpetual Motion Machine in a Positive Feedback Loop. --------- Third, Trenberth's Energy Budget Diagram clearly shows 324 w/m^2 of Back Radiation from the Colder atmosphere being ABSORBED by a warmer Earth surface ! http://www.windows.ucar.edu/tour/link=/earth/climate/greenhouse_effect_gases.html Again, EXACTLY THE OPPOSITE OF YOUR RANT ! --------- Fourth, John Cook's response to my very first Post #15 said: "Response: The atmosphere doesn't create energy. Greenhouse gases absorb outgoing infrared energy, preventing some of it from escaping out to space. The absorbed infrared energy is then reemitted in all directions, some of it heading back to Earth where it warms the surface. It's not an argument or a theory that CO2 causes global warming. It's an experimentally observed physical reality." Again, EXACTLY THE OPPOSITE OF YOUR RANT ! ---------------------- It is obvious that YOU don't understand the Greenhouse Effect, no matter how many times it is shown to you! And, it is YOU that is uses "False Logic" and YOUR argument "fundamentally fails" because it's based on "semantic confusion of heat and radiation." !! ----------------------- Next, You said... "2. The accumulation of thermal energy in the earth system under a positive radiative imbalance obviously doesn't require the "creation of energy". Your non-sequiter ("the sun is the ONLY energy source"...therefore increased thermal energy in the climate system under radiative imbalance is "a violation of The Law of Conservation of Energy") is just silly...it's equivalent to asserting that the analogy of water flowing through a reservoir under constrained outflow (my posts #41 and #43) requires "creation of mass", when nothing is being "created"; the thermal energy (or water) is simply accumulating." There is NO OTHER Energy source besides the SUN! Proof: If the Sun were removed, the Earth and Atmosphere would rapidly cool to near absolute zero!! Your argument is the same as saying your MP3 player will continue to operate when the battery is removed !! Geez, this is as fundamental as it gets. Read the Greenhouse Effect links above, they ALL create energy ! Is 390 w/m^2 of Earth Radiation greater than the 168 w/m^2 of Solar Energy heating the Earth? A CLEAR CREATION OF ENERGY! Trenberth's Energy Budget claims that the Sun, Earth and Atmosphere ARE IN RADIATIVE BALANCE ! That's why he claimes that the in-coming 235 w/m^2 of Solar Energy is BALANCED by the 235 w/m^2 out-going IR radiation ! Again, EXACTLY THE OPPOSITE OF YOUR RANT ! And, The Law of Conservation CANNOT EVER be VIOLATED...no matter how "silly" you think Laws of Science are. ----------------------------- Like I said... You just provide your "OPINIONS" ! Face the FACTS: - You have not produced ANY argument for my posts based on any Physics! - ALL your posts are just your "opinions" with ZERO Back-up. You should spend more time reading the Laws of Science and getting your facts straight before babbling your uninformed "opinions". HAHAHA...you are hilarious!
    0 0
  9. Steve - re:your post #56 Geez Steve, what other energy source other than the Sun, is capable of heating the Earth to +15 deg C ? It just takes a "piddly" 390 w/m^2 X Surface Area of The Earth = 390 w/m^2 X 4 X Pi X Radius^2 = 390 X 4 X Pi X (6.371 x 10^6)^2 = 1.99 X 10^17 watts....that's all. Any Ideas? -------------- Here are some Calculations for Mars and Venus. Venus "The atmospheric mass is 93 times that of Earth's atmosphere while the pressure at the planet's surface is about 92 times that at Earth's surface..." Surface temp (mean) 735K or 461.85 deg C It has an atmosphere that is composed of 96.5% CO2. http://en.wikipedia.org/wiki/Venus Mars, atmosphere "The surface pressure on Mars is only about 0.7% of the average surface pressure at sea level on Earth." It has an atmosphere that is composed of 95.3% CO2. The surface temp is about 250K or -23 deg C. http://www.daviddarling.info/encyclopedia/M/Marsatmos.html Solar Constants Venus (2647 w/m^2 - 2576 w/m^2)= average of 2611.5 w/m^2 Mars (715 w/m^2 - 492 w/m^2)= average of 603.5 w/m^2 http://en.wikipedia.org/wiki/Solar_constant#Solar_constant Heating due to the Solar Constants/4 using Stephan Boltzman Law and (albedo = 0): Venus = 327.58 K or +54.43 deg C Black body temp. Mars = 227.12 K or -46.03 deg C Black body temp. With the addition of an atmosphere the temp increases are: Venus = 735K - 327.58K = 407.42K (461.85 C - 54.43 C = 407.42 deg C) Mars = 250K - 227.12K = 22.88K (-23 deg C -(-46.03 C)= 23 deg C) It should be obvious that Venus and Mars have about the same amount of CO2 in their atmosphere (96.5% and 95.3%) yet their temperature increases due to the addition of an atmosphere vary by 407.42 deg C - 23 deg C = 384.42 deg C! CO2 obviously does NOT have any effect on the temperature increases of these planets. The Ideal Gas Law PV = RT gives the general relationship between Pressure P and temperature T. Venus has a much larger atmospheric pressure than Mars thus the Venus temperature is much higher than Mars! CO2 has absolutely nothing to do with these planetary temperatures! ---------------------- Re: Your link: http://skepticalscience.com/How-do-we-know-CO2-is-causing-warming.html I take it that you want me to explain the "Measurements of downward longwave radiation" ? Well, I have already done that. See my post #16, where I show: "All the Instruments used to measure the so called "Greenhouse Effect" prove that it does not exist! They use IR detectors that have been COOLED far below the -20 deg C atmosphere temperature to make the direct measurement POSSIBLE." I then give the Specs's for the AIRS Instrument and TES Instrument and their IR Detector COOLING temperatures that make the direct Back Radiation measurements possible. Then look at my Post #18 where I provide a link to a paper and measurements done by the Physics Dept. of Brigham Young University proving that Back Radiation cannot reach the Earth. ----------------- Now it's YOUR TURN to provide some very basic answers. 1. Please supply ANY Law of Science that supports the "Greenhouse Effect" and AGW. 2. Please supply ANY Measurement that shows that CO2 in a Colder Atmosphere can Heat up a Warmer Earth. 3. Please describe (and back-up by Physics) how a -20 deg C atmosphere can heat a -18 deg C Earth up by 33 deg C to a whopping +15 deg C. There has been over $200 Billion spent on AGW, there are thousands of papers on AGW, the IPCC has written several reports on it and countless "Scientists" say AGW is real. So, this should a "snap" for you to produce....right? Good Luck!
    0 0
  10. shawnhet - re: your post#54 No, I'm not "off base". The Spherical Earth receives Solar Flux at an angle at all points except the Equator. It is only the vector portion of the flux that is 'normal' to the surface that will cause heating. All 'normals' to a spherical surface will be on a line passing through the center of the sphere. When you Integrate Solar Flux over the Spherical surface (this is called a surface Integral) facing the Sun, it is done by using a projection of the sphere onto a 2D plane. This projection is a disk (actually a circle) that has an Area = Pi X Radius^2. It will produce a Solar Flux density averaged over the disk with no variations for the Equator or any lattitude. You can see the development of this equation here: The Solar Radiation received by the Earth (modelled as a disk, a projection of a sphere onto a 2D plane) represents an average flux density over the entire spherical surface facing the Sun. This quantity is called PEabs, the average solar energy absorbed by the Earth facing the Sun. The emitted energy uses the Earth as a sphere. This is called PEemt. The two quantities are then equated and this equation is the result: TE = TS (((1-a)^0.5 * Rs)/(2*D))^0.5 So this equation represents the Solar Energy received by a disk Earth facing the Sun and emitted by a fully spherical Earth. TE is an average Night and Day temperature in absence of an atmosphere. http://en.wikipedia.org/wiki/Black_body ------------ To get the equation for the Earth as a sphere one just has to substitute the area of a sphere A = 4 X Pi X Radius^2 in place of A = Pi X Radius^2. And, you get this equation: TE = TS ( ( (1-a)^0.5 * Rs)/D) ) )^0.5) This will give the temp for Max Solar energy at the Earth's equator...not an average Earth temp. Hope this helps.
    0 0
  11. NASA now has a site for neat summaries of the data - http://climate.nasa.gov
    0 0
  12. Gord, I don't understand your point. I think we more or less agree up until the point where you calculate (for all practical purposes) how much energy would be absorbed if we peeled the "skin" off the Earth and stretched it out into a disk equi-distant to the sun(than it is now). The fact is your value as presented has no physical meaning. The Earth does have a night period and a day period and the energy of the Earth as a whole must take this into account. If you want to calculate the maximum insolation received by some portion of the Earth for some portion of the day, that's great, but it needs to be placed in some kind of context to have any meaning to the behavior of the Earth as a whole(IOW it has to be averaged or distributed somehow). IAC, your post to me has two different equations to allow you to derive the temperature of the Earth and they must be mutually contradictory(when you equate the 2 expressions for TE, you end up with D=2D such that D cannot equal 0). Cheers, :)
    0 0
  13. Question for Gord How does one explain the following... During two consecutive nights in a high desert location, there is no appreciable wind at ground level for two days. On the first night temperatures drop to 5 degrees C, while and on the second it goes below freezing. The only observed conditions at ground level between one night and the next were the high clouds of the first night. Most people usually attribute the warmer night to the cloud coverage that seems to act as a "blanket". Is there some fallacy to this model, and if so, what would be a better way to describe what is going on?
    0 0
  14. Shawnhet - re: your Post#62 Here is another way to look at it. The Solar Constant is the Solar Flux reaching the Earth before the Disk Averaging takes place. The Solar Constant for a Sun temp of 5778 K is 1368 w/m^2. To get the Earth as a Disk average you simply divide the 1368 w/m^2 by 4 to get 342 w/m^2 which is used by Trenberth's Energy Budget Diagram as the average Solar radiation at the top of the atmosphere. The 342 w/m^2 is the average Day and Night Solar insolation. The reason you divide by 4 is Area of Sphere = 4*Pi*R^2 and Area of Disk = Pi*R^2 has a ratio of 4 to 1. Without the Disk Averaging all the Solar Constant 1368 w/m^2 would be received at the Earth's equator and less at other latitudes because of the angle of the higher latitudes. Zero w/m^2 will be received at the Poles. The two equations describe the two situations. Hope this helps.
    0 0
  15. RSVP - re:your post #63 The answer is Adiabatic Warming. Here is a link. Adiabatic temperature change and stability http://www.uwsp.edu/geO/faculty/ritter/geog101/textbook/atmospheric_moisture/lapse_rates_1.html
    0 0
  16. Um... But Gord, the very same online book you just cited in comment 65 answers RSVP's question exactly the way RSVP said that most people answer it, and also explicitly states that air transfers energy down toward the surface. See http://www.uwsp.edu/geo/faculty/ritter/geog101/textbook/temperature/temperature_radiation_heat_p_2.html
    0 0
  17. Tom Dayton - re:your post #66 The difference is that Adiabatic Warming does NOT VIOLATE the 2nd Law of Thermodynamics! "These clouds absorb the radiation emitted by the earth and radiate it back down toward the earth's surface, warming the air." http://www.uwsp.edu/geo/faculty/ritter/geog101/textbook/temperature/temperature_radiation_heat_p_2.html “Second Law of Thermodynamics: It is not possible for heat to flow from a colder body to a warmer body without any work having been done to accomplish this flow. Energy will not flow spontaneously from a low temperature object to a higher temperature object.” http://hyperphysics.phy-astr.gsu.edu/hbase/thermo/seclaw.html#c3 Hmmm, now which one should I believe, the one that complies with Laws of Science or the one that violates Laws of Science?
    0 0
  18. Gord, many people already tried to show you where your pedantic and obsessively repeated reasoning is faulty. I'll try with simpler physics that I hope you manage better. Just my two cents. The sun is heating the earth, no questions about it. Given a constant power input, a body will warm indefinitely unless there is a mechanism of dissipating it; in this case, the body will exponentially approach an equilibrium temperature. If you put a suitable thermal insulator, you reduce heat dissipation and the equilibrium temperature will be higher. Is it the thermal insulator that heats the body? Definitely not. Is the thermal insulator warmer than the body? Clearly not, there will be a temperature gradient inside it (and in the right direction, also!). But it's effective in reducing heat dispertion and this results in a higher equilibrium temperature. Does this violate thermodynamics? Absolutely not, the outgoing flux is just reduced, didn't reverse. By the way, you used this very same concepts in #16 without even realizing it. You correctly wrote P = e*BC*A(T^4 – Tc^4); the two terms are two fluxes in the oppostite direction, one coming from a cooler body. Only after this point is clear, which appers to not be the case up to now, we can continue on how the thermal insulation works in the case of the earth atmosphere. P.S. Think about this, a random sequence of correct statements does not make the conclusions right.
    0 0
  19. Riccardo - re: your post #68 You said... " But it's effective in reducing heat dispertion and this results in a higher equilibrium temperature." "...the outgoing flux is just reduced, didn't reverse." Wrong. All heat energy absorbed is radiated!...there is no "reducing heat dispersion" or "higher equilibrium temperature"! I already explained that the Earth at +15 deg C will radiate 390 w/m^2...always. The warmer Earth radiates 390 w/m^2 and heats up the atmosphere to -20 deg C. The atmosphere will radiate 324 w/m^2 in all directions...always. Between the Earth and Atmosphere the resultant EM field is (390-324) 66 w/m^2 in an upward direction. Past the atmosphere the Resultant EM field is 66 w/m^2 PLUS 324 w/m^2 for a total of 390 w/m^2 in an upward direction to cold space. ALL the 390 w/m^2 radiated by the Earth is radiated to cold space. If you removed the atmosphere, the Earth would still radiate 390 w/m^2 to cold space ! There is no "reducing heat dispersion" or "higher equilibrium temperature"! And, the "outgoing flux" IS NOT REDUCED!!! --------------------------- You said... "By the way, you used this very same concepts in #16 without even realizing it. You correctly wrote P = e*BC*A(T^4 – Tc^4); the two terms are two fluxes in the oppostite direction, one coming from a cooler body. "Only after this point is clear, which appers to not be the case up to now, we can continue on how the thermal insulation works in the case of the earth atmosphere." HUH?....P = e*BC*A(T^4 – Tc^4) = P/A = e*BC*T^4 – e*BC*Tc^4 (Watts/m^2) This is an obvious subtraction of two Electromagnetic Fields. This is EXACTLY what I used for "Between the Earth and Atmosphere the resultant EM field is (390-324) 66 w/m^2 in an upward direction." !! What do you mean by "Only after this point is clear, which appers to not be the case up to now, we can continue on how the thermal insulation works in the case of the earth atmosphere." ???? ----------------------------------- P.S. Think about this, a random sequence of correct statements HAS MADE THE CONCLUSIONS RIGHT!
    0 0
  20. I really appreciate this blog! As for this post, I wonder about two things: 1. What does the track racord until now tell us about the _net_ forcing (all feedbacks inclusive) from the CO2 increase we have had? Does it clearly show that the estimates of about 2 oC/doubling are the most plausible, given all data? (Maybe I should have known this, but I don't.) 2. Is the net feedback effect a stable and well-defined entity, or is it the average of several different terms, which may vary with a set of conditions? Has it been investigated whether variation in feedback may partially explain som of the climatic variability? ( Again, maybe I should have known this, but I don't.)
    0 0
  21. To Gord If greenhouse warming is not real, what then do you attribute global warming to? I suppose you dont have to have a theory, but it would be interesting to know if you do.
    0 0
  22. RSVP, Oh there is Global Warming, we are coming out of an Ice Age....just like we have many times before. The reason for Global Warming is the same as always...the ONLY ENERGY SOURCE....THE SUN.
    0 0
  23. Gord, "All heat energy absorbed is radiated!...there is no "reducing heat dispersion" or "higher equilibrium temperature"! You are compleately missing that there is earth, there is the atmosphere and there is empty space outside. Consider the whole system, not just a piece of it. "I already explained that the Earth at +15 deg C will radiate 390 w/m^2...always." Yes, all the bodies at a certain temperature will radiate a fixed amount of energy. No doubt. But again, you are not considering atmosphere and free space and then the total energy balance. "This is an obvious subtraction of two Electromagnetic Fields." And that's what we called IR radiation, indeed. And that's what is moving energy from the sun toward the earth and from the earth to outside space through the atmosphere. It's indeed the very same flux i'm talking about. "What do you mean by "Only after this point is clear, which appers to not be the case up to now, we can continue on how the thermal insulation works in the case of the earth atmosphere." ????" I mean that if we do not first fix the misconceptions in basic physics we can go nowhere.
    0 0
  24. Gord, I agree that the Earth absorbs as a disk and emits as a sphere. However, that fact is already taken into account in your **first** expression - TE = TS (((1-a)^0.5 * Rs)/(2*D))^0.5. Your second expression is mistaken(it has to be wrong if your first expression is accurate). Check the derivation of it here(about 2/3 of the way down the page). http://en.wikipedia.org/wiki/Black_body The reason for the division 1368 by 4(when you are calculating the energy **absorbed** by the Earth) is not to relate it to the surface of the sphere, but rather to average it over the day-night period and to account for the shape of the Earth (as you say here) "It is only the vector portion of the flux that is 'normal' to the surface that will cause heating. All 'normals' to a spherical surface will be on a line passing through the center of the sphere.". Cheers, :)
    0 0
  25. Gord, Upon thinking about it, I find that it is equivalent to say that one divides the energy received by the sun(1368Wm-2) by the surface area of the Earth and to use the explanation I gave in my last post. This doesn't change the fact that the following expression doesn't work to calculate the temperature of the Earth. TE = TS ( ( (1-a)^0.5 * Rs)/D) ) )^0.5) Cheers, :)
    0 0
  26. Riccardo - Re:your Post #73 You said... "You are compleately missing that there is earth, there is the atmosphere and there is empty space outside. Consider the whole system, not just a piece of it." "Yes, all the bodies at a certain temperature will radiate a fixed amount of energy. No doubt. But again, you are not considering atmosphere and free space and then the total energy balance." Read my post #69 again...the Earth, atmosphere and cold space were all included in the calculations.
    0 0
  27. shawnhet - re: your posts #74 and #75 Here is the derivation of the equation. BC = Boltzmann's Constant Te = blackbody temp of the Earth Ts = surface temp of the Sun Rs = radius of the Sun D = distance between the Sun and Earth a = albedo of the Earth Psemt = (BC*Ts^4)(4*pi*Rs^2)....energy emitted by the Sun Peabs = Psemt(1-a)(Pi*Re^2)/(4*pi*D^2)....energy absorbed by the Earth as a "disk" Substitute (4*pi*Re^2) for (Pi*Re^2) to get Earth as a "sphere" Peabs = Psemt(1-a)(4*Pi*Re^2)/(4*pi*D^2)....energy absorbed by the Earth as a "sphere" Peabs = (BC*Ts^4)(4*pi*Rs^2)(1-a)(4*Pi*Re^2)/(4*pi*D^2)....energy absorbed by the Earth as a "sphere" after replacing Psemt. Peabs = (BC*Ts^4)(4*pi*Rs^2)(1-a)(Re/D)^2....energy absorbed by the Earth as a "sphere" Peemt = (BC*Te^4)(4*pi*Re^2)......energy emitted by the Earth as a sphere Equating... Peemt = Peabs gives: (BC*Te^4)(4*pi*Re^2) = (BC*Ts^4)(4*pi*Rs^2)(1-a)(Re/D)^2 (BC*Te^4)/(BC*Ts^4) = (1-a)(Re/D)^2(4*pi*Rs^2)/(4*pi*Re^2) (Te/Ts)^4 = (1-a)(Re/D)^2(Rs/Re)^2 Taking the square root of both sides gives: (Te/Ts)^2 = (1-a)^0.5(Re/D)(Rs/Re) (Te/Ts)^2 = (1-a)^0.5(Rs/D) (Te/Ts)^2 = ((1-a)^0.5 *Rs)/D Taking the square root of both sides again gives: Te/Ts = ((1-a)^0.5 *Rs)/D)^0.5 Te = Ts (((1-a)^0.5 *Rs)/D)^0.5) And what I posted was: TE = TS (((1-a)^0.5 * Rs)/D)))^0.5) Which I typed too many brackets in, but does not change the result. This equation gives the temperature of the Earth at the equator. Hope this helps.
    0 0
  28. Gord, no need to read it again. You did not consider the atmosphere for what it really is and that's explain, i hope, what i said. You simply did elementary calculations of the electromagnetic fluxes of an immaginary static system at fixed temperature and with no absorpion. It should be clear that it does not apply in our case.
    0 0
  29. Gord, What would be the effective temperature of the Earth as seen from space? According to Wiens Law, what does the Earth radiating at 10 microns indicate as it's temperature. What is the globally averaged surface temperature of the Earth? Why the difference?
    0 0
  30. Gord, Your problem appears to start in this line "Substitute (4*pi*Re^2) for (Pi*Re^2) to get Earth as a "sphere" " In this step you don't do what you have done above, you should equate what Earth absorbs as a disc (from the Sun) to what it emits as a sphere to space. (4*pi*Re^2) does not equal (Pi*Re^2) so when you substitute it in you are changing the value. (Obviously, you can only substitute two quantities that are equal). A brief scan of the rest of your work seems to show that it is fine, but the Earth does not *absorb* as a sphere, it *emits* as a sphere. Cheers, :)
    0 0
  31. Gord, You stated: ALL the 390 w/m^2 radiated by the Earth is radiated to cold space. If you removed the atmosphere, the Earth would still radiate 390 w/m^2 to cold space ! -------- Whatever the actual numbers are, the fact remains that all energy received from the Sun will eventually be emitted back to space as you state. The issue is from where most of this energy is radiated as seen from space. Most does not radiate directly from the surface, but rather from high in the troposphere because the lower atmosphere is made opaque to infrared radiation by the presence of greenhouse gases absorbing to extinction. The 255K effective temperature of the Earth is thus apparent from a globally averaged 16,000' above Earth's surface (layer of emissivity) due to the greenhouse effect rather than at the surface which averages 288k.
    0 0
  32. Gord, From post #58: Both examples violate the 2nd Law because there is heat energy flowing from a colder atmosphere to a warmer Earth. The above Greenhouse Effect links describe a Perpetual Motion Machine, actually a Perpetual Motion Machine in a Positive Feedback Loop. ----------- Greenhouse gases are very effectively absorbing IR, as is often stated by skeptic, IR absorption is "saturated" within the first 10 meters of Earth's surface. That first 10 meters of atmosphere is usually very nearly the same temperature as the underlying surface because it is directly exchanging energy with the surface by conduction, convection and radiation. Because of the saturation within the first 10 meters, the surface is directly exchanging energy radiatively only with that layer. The first 10 meters exchanges directly with the next higher layer and so on...until the radiation is finally released at 255K. Warmer objects receive radiative energy from cooler objects, the radiation does not raise the warmer objects temperature, but the energy doesn't just disappear. It is absorbed by the warmer object so that it cools more slowly than if it were not exchanging energy with other near by matter.
    0 0
  33. shawnhet - re:your post#80 One last time... Look at my Post #64 regarding the Solar Contant. "The Solar Constant for a Sun temp of 5778 K is 1368 w/m^2. To get the Earth as a Disk average you simply divide the 1368 w/m^2 by 4 to get 342 w/m^2 which is used by Trenberth's Energy Budget Diagram as the average Solar radiation at the top of the atmosphere. The 342 w/m^2 is the average Day and Night Solar insolation. The reason you divide by 4 is Area of Sphere = 4*Pi*R^2 and Area of Disk = Pi*R^2 has a ratio of 4 to 1. Without the Disk Averaging all the Solar Constant 1368 w/m^2 would be received at the Earth's equator and less at other latitudes because of the angle of the higher latitudes. Zero w/m^2 will be received at the Poles. The two equations describe the two situations." If you use the full 1368 w/m^2 (which is what would be received at the equator) you can calculate the temp of the Earth TE: SC * (1-a) = BC * TE^4 TE = (SC * (1-a)/BC)^0.25 where SC = Solar Constant (1368 w/m^2) a = albedo of the Earth (0.3) BC = Boltzmann Constant (5.67 X 10^-8) TE = Black Body Earth temp in K Gives: TE = 360.50 deg K TE = 87.35 deg C Here is my equation with the Earth as Sphere for receiving the Solar Energy Te = Ts (((1-a)^0.5 *Rs)/D)^0.5) Where TE is blackbody temp of the Earth in K TS is the surface temp of the SUN in K = 5778 Rs is radius of the Sun = 6.96X10^8 D is distance between the Sun and Earth in m = 1.496X10^11 a is albedo of the Earth = 0.3 Result: TE = 360.49 K or 87.34 deg C!! --------------------------------------- The results are the SAME!
    0 0
  34. Riccardo - Re:your Post #78 You said... "You simply did elementary calculations of the electromagnetic fluxes of an immaginary static system at fixed temperature and with no absorpion. It should be clear that it does not apply in our case." I DID USE THE ABSORBTION OF THE ATMOSPHERE !!! Again, ALL heat energy ABSORBED is RADIATED!!! The Earth Radiates 390 w/m^2 and the Atmosphere ABSORBS and RADIATES 324 w/m^2 in all directions. These numbers came directly from Trenberth's Energy Budget Diagram!!!! http://www.windows.ucar.edu/tour/link=/earth/climate/greenhouse_effect_gases.html Now, if you have a problem with the ABSORBTION numbers, I suggest you complain to Trenberth....NOT ME!
    0 0
  35. Gord, the hypothetical temperature of the equator in isolation is not the same as the temperature of the Earth as a whole. Thus, your TE is not "TE = Black Body Earth temp in K" as you have stated. I don't have an issue with dividing the SC by 4 to get the average energy received by a square meter on the Earth's surface. What you seem not to understand is that the textbook derivation of Earth's blackbody temperature *already* takes into account the fact that that a square meter near the equator absorbs ~ 4 times this average value. No matter how you slice it, the Earth does not receive energy as a sphere as you claim here "Here is my equation with the Earth as Sphere for receiving the Solar Energy Te = Ts (((1-a)^0.5 *Rs)/D)^0.5)". However, some sections of the Earth do receive nearly the full value of the solar constant while the sun is shining(for instance, a black parking lot on a clear day in Saudi Arabia, perhaps). Cheers, :)
    0 0
  36. WeatherRusty - Re:your Post#79 The Earth's average temperature is +15 deg C. The SUN is the ONLY energy source, the Atmosphere and the Earth ARE NOT ENERGY SOURCES. Proof: If the Sun were removed, the Earth and atmosphere would rapidly cool to near absolute zero. The Atmosphere and the Earth cannot Create Energy. Conclusion: The Earth's temperature of +15 is CAUSED by the ONLY ENERGY SOURCE....THE SUN! ----------------- To suggest that the Sun is NOT the cause of the Earth's temperature is the same as saying that your MP3 player is not powered by it's battery. It's powered by CO2 that somehow generates electricity. That's an equivalent Fantasy to the "Greenhouse Effect" Fantasy.
    0 0
  37. WeatherRusty - Re:your Post#82 Heat transfer by Radiation has been identified as the "vehicle" for AGW and the "Greenhouse Effect". This is apparent in ALL the AGW literature. I already provided several AGW links to the "Greenhouse Effect". Trenberth's Energy Budget Diagram shows Back Radiation from a much colder atmosphere heating a warmer Earth. The IPCC uses Trenberth's Energy Budget Diagram throughout it's reports and uses an atmospheric temperature of -19 deg C in it's reports: "The energy that is not reflected back to space is absorbed by the Earth’s surface and atmosphere. This amount is approximately 240 Watts per square metre (W m–2). To balance the incoming energy, the Earth itself must radiate, on average, the same amount of energy back to space. The Earth does this by emitting outgoing longwave radiation. Everything on Earth emits longwave radiation continuously. That is the heat energy one feels radiating out from a fire; the warmer an object, the more heat energy it radiates. To emit 240 W m–2, a surface would have to have a temperature of around –19°C. This is much colder than the conditions that actually exist at the Earth’s surface (the global mean surface temperature is about 14°C). Instead, the necessary –19°C is found at an altitude about 5 km above the surface." http://www.ipcc.ch/pdf/assessment-report/ar4/wg1/ar4-wg1-faqs.pdf You should read the AGW literature before making comments. - ALL the AGW'er literature IGNORE the FACT that the SUN is the ONLY Energy Source. - They ALL use a COLDER atmosphere to HEAT a Warmer Earth. - They ALL use "Creation of Energy" by the Earth and Atmosphere. ----------------- You said.... "Warmer objects receive radiative energy from cooler objects, the radiation does not raise the warmer objects temperature, but the energy doesn't just disappear. It is absorbed by the warmer object so that it cools more slowly than if it were not exchanging energy with other near by matter." What Laws of Science supports this "Fantasy" statement? I can tell tell you the Laws of Science that your "Fantasy" statement VIOLATES! You said ... "Warmer objects receive radiative energy from cooler objects.." That VIOLATES the 2nd Law of Thermodynamics: You said.... "....the radiation does not raise the warmer objects temperature, but the energy doesn't just disappear. It is absorbed by the warmer object..." And, that VIOLATES Two Laws of Science ! All objects that Absorb energy HAS to increase in temperature!...a VIOLATION of the Stefan-Boltzmann Law. If the object aborbed energy and DID NOT increase in temperature then the energy would HAVE to disappear!....a VIOLATION of The Law of Conservation of Energy. ---------------------- Your post is rife with errors and violations of numerous Laws of Science.
    0 0
  38. WeatherRusty - Re:your Post#81 First, the atmosphere Radiates ALL the heat energy it absorbs and it DOES NOT AFFECT THE EARTH'S SURFACE AT ALL! There is absolutely no back radiation from the colder atmosphere reaching the Earth's surface at all...let alone heating the Earth. The Earth's radiation heats the Greenhouse Gases (because of the emissivity) to -20 deg C....that's all! The "Greenhouse Effect" that relies on a colder atmosphere heating a warmer Earth DOES NOT EXIST. The fantasy "Greenhouse Effect" is PROVEN to not Exist because: 1. It would VIOLATE the 2nd Law of Thermodynamics. 2. It would VIOLATE the Law of Conservation of Energy. 3. ALL actual measurements PROVE that it does not exist. -------- If YOU still think it exists then provide these very basic answers: 1. Please supply ANY Law of Science that supports the "Greenhouse Effect" and AGW. 2. Please supply ANY Measurement that shows that CO2 in a Colder Atmosphere can Heat up a Warmer Earth. 3. Please describe (and back-up by Physics) how a -20 deg C atmosphere can heat a -18 deg C Earth up by 33 deg C to a whopping +15 deg C. There has been over $200 Billion spent on AGW, there are thousands of papers on AGW, the IPCC has written several reports on it and countless "Scientists" say AGW is real. So, this should a "snap" for you to produce....right? Good Luck!
    0 0
  39. Shawnhet - re: your Post#85 Summary: 1. This equation gives the AVERAGE Earth temperature (Day and Night) for Solar Energy received by the Earth as "disk". TE = TS (((1-a)^0.5 * Rs)/(2*D))^0.5 Where TE is blackbody temp of the Earth in K TS is the surface temp of the SUN in K = 5778 Rs is radius of the Sun = 6.96X10^8 D is distance between the Sun and Earth in m = 1.496X10^11 a is albedo of the Earth = 0.3 Gives TE = 254.90 K or -18.25 deg C 2. This equation gives the Earth temperature for Solar Energy received by the Earth as a "sphere". It will give the Earth temperature at the equator. Te = Ts (((1-a)^0.5 *Rs)/D)^0.5) Where TE is blackbody temp of the Earth in K TS is the surface temp of the SUN in K = 5778 Rs is radius of the Sun = 6.96X10^8 D is distance between the Sun and Earth in m = 1.496X10^11 a is albedo of the Earth = 0.3 Result: TE = 360.49 K or 87.34 deg C. 3. This equation gives the Earth temperature for Solar Energy received by the Earth as a "sphere". It uses the full amount of the Solar Constant (1368 w/m^2) being received at the Earth's equator. SC * (1-a) = BC * TE^4 TE = (SC * (1-a)/BC)^0.25 where SC = Solar Constant (1368 w/m^2) a = albedo of the Earth (0.3) BC = Boltzmann Constant (5.67 X 10^-8) TE = Black Body Earth temp in K Gives: TE = 360.50 deg K TE = 87.35 deg C --------------------------------- Now, Please show your calculations for the Earth temperature at the Equator. -----------------------------------
    0 0
  40. Gord, I don't have an issue with your temperature calculation for the equator during the day, but you have labelled it wrongly again. This is not the Black Body temperature of the *Earth*, but only of a portion of it (during the day). It has nothing to do with the Earth receiving energy as a sphere, it has to do with the fact that the equator is the part of the Earth that is directly facing the sun. Other parts of the globe have the sun's light hit them at an angle(as I think you have already agreed). IAC, I still don't understand what relevance you think this value has for the Earth as a whole, as I've been saying since at least post #62. Cheers, :)
    0 0
  41. Shawnhet - re:your post #90 It has EVERYTHING to do with the Earth as a Sphere! That's why Area of Sphere = 4*Pi*R^2 was substituted for Area of Disk = Pi*R^2 !!! And, that's why it applies to the Equator, the only point on the the Earth that is "perpendicular" to Solar Flux !!! Exactly like said in my post#54 to you! "To get the equation for the Earth as a sphere one just has to substitute the area of a sphere A = 4 X Pi X Radius^2 in place of A = Pi X Radius^2. And, you get this equation: TE = TS ( ( (1-a)^0.5 * Rs)/D) ) )^0.5) This will give the temp for Max Solar energy at the Earth's equator...not an average Earth temp."
    0 0
  42. Gord, your expression was wrongly labelled and has been from the beginning(Te should be blackbody temp of the equator, perhaps, cetainly not of the Earth). It is true that the equator during the day absorbs the same amount of energy as if we had peeled the entire surface area of the Earth's sphere and laid it out facing the sun. However, this is a very confusing way of formulating it IMO and combined with the poor labelling makes you very difficult to understand. I still don't see what the point of calculating this is though. Clearly, the equator doesn't exist in isolation. Cheers, :)
    0 0
  43. Shawnhet - re:your post #92 There was no "peeling" of the Earth's surface and laying it out to face the Sun !! The Earth....ROTATES! and there is ALWAYS a MUCH greater warming at the Equator as it ROTATES!! The "point" was stated in my Post#50 to Chris: "Result: TE = 360.49 K or 87.34 deg C!! That's the energy that the Ocean can store at the equator and distribute over the Earth by conduction."
    0 0
  44. Gord, To help me understand what you're thinking, let's switch the topic from absorption-and-re-emission to good old-fashioned reflection. In my lab I shine an infrared flashlight at a mirror, and measure more infrared coming from the mirror when that flashlight is turned on than when it is turned off. I conclude that the mirror reflects infrared from my flashlight. Do you agree with my conclusion? I take that mirror outside at night and suspend it above the ground, with its reflecting surface facing the ground. I measure more infrared coming from the mirror than from the empty sky next to the mirror. I conclude that the mirror reflects infrared from the ground. Do you agree with my conclusion?
    0 0
  45. Gord, yes it rotates, but it never **at any point** has more than an area of pi*r2 facing the sun at any time. There is never an area of 4pi*r2 that is illuminated by the sun. You were subbing a non-existent/imaginary area into an equation to allow you to calculate the actual energy received by a real *section* of the Earth all the while labelling your expression wrongly. I think most folks would find that confusing. Anyways, if your point is that if the equator existed in isolation and *did not* rotate it could heat its surface to 87C from solar radiation alone, I agree with you. However, neither of those qualifiers apply. Cheers, :)
    0 0
  46. Gord, By the application of your "physics" the Sun would instantly implode and Earth's liquid core would have long ago solidified. Your understanding of the greenhouse effect and radiative transfer is totally wrong. You do seem to understand the Laws of Thermodynamic but your failure to comprehend how radiation interacts with matter leads you to believe those laws are violated.
    0 0
  47. Shawnhet - re:your Post #95 The facts are that the Oceans are warmer at the equator than other latitudes and the reason is the direct heating of Solar Energy at the equator. As the latitude increases there is progressively less heating of the Oceans by Solar Energy. Heat conduction, convection and Ocean currents due to the Earth's rotation (Coriolis acceleration) ensure heat transfer to colder Ocean waters. ---------- See SOLAR RADIATION ENTERING THE EARTH SYSTEM and Insolation: Solar Radiation Striking the Surface I = S cos Z I= Insolation S~ 1000 W/m2 (Clear day solar insolation on a surface perpendicular to incoming solar radiation. This value actually varies greatly due to atmospheric variables.) Z = Zenith Angle (Zenith Angle is the angle from the zenith (point directly overhead) to the Sun's position in the sky. The zenith angle is dependent upon latitude, solar declination angle, and time of day.) http://edmall.gsfc.nasa.gov/inv99Project.Site/Pages/science-briefs/ed-stickler/ed-irradiance.html ---------- PHYSICAL OCEANOGRAPHY See the Sea Surface Temperature (Mean)(2nd row first graph) for the Ocean temperature at the equator. The mean Sea Surface Temperature IS 29 deg C at the Equator. (If you take the area under the curve with AutoCad the average temp occurs at a 40 deg latitude and the temperature is 18.7 deg C.) http://www.ngdc.noaa.gov/mgg/geology/hh1996/ocean.html
    0 0
  48. Tom Dayton - re:your Post #94 Your questions can't be answered directly. Reflection and/or emission of Electromagnetic Fields and resultant Vector summation or subtraction depends entirely on the reflecting/emitting surfaces and the point chosen for analysis. Review these links: 1. Vector addition of fields... http://hyperphysics.phy-astr.gsu.edu/hbase/electric/mulpoi.html#c3 2. Cancellation of Light http://www.exploratorium.edu/ronh/bubbles/bubble_colors.html http://webexhibits.org/causesofcolor/15F.html http://micro.magnet.fsu.edu/optics/lightandcolor/interference.html -------------------------------- The cancellation of light links show how constructive or destructive interference of EM fields work in the time domain. Vector summation of EM fields is usually used for actual calculations.
    0 0
  49. WeatherRusty - re:your Post#96 You said... "By the application of your "physics" the Sun would instantly implode and Earth's liquid core would have long ago solidified." Where did you dream that up that little "gem of wisdom" and what "Physics" are you talking about? ------------------ You said... "Your understanding of the greenhouse effect and radiative transfer is totally wrong. You do seem to understand the Laws of Thermodynamic but your failure to comprehend how radiation interacts with matter leads you to believe those laws are violated." Again, you just are "babbling" your "opinion" with no specifics or back-up. I have already shown in my Post #87 that you have an astonishing ability to create posts that are rife with errors and numerous violations of Laws of Science. ----------------- Any luck coming up with these items? 1. Please supply ANY Law of Science that supports the "Greenhouse Effect" and AGW. 2. Please supply ANY Measurement that shows that CO2 in a Colder Atmosphere can Heat up a Warmer Earth. 3. Please describe (and back-up by Physics) how a -20 deg C atmosphere can heat a -18 deg C Earth up by 33 deg C to a whopping +15 deg C. There has been over $200 Billion spent on AGW, there are thousands of papers on AGW, the IPCC has written several reports on it and countless "Scientists" say AGW is real. So, this should a "snap" for you to produce....right? Good Luck!
    0 0
  50. Ah, your answer helped me understand your perspective, Gord. How about this situation? No flashlight, no lab. Just walk into your bathroom, turn on the lamp, stand in front of the mirror, adjusting your position until you see yourself in the mirror. Please do that right now so we aren't talking about a hypothetical situation, but a completely real, concrete one that you personally experienced. I believe that the reason you saw yourself is that light from the bathroom lamp reflected off your face to the mirror, then reflected off the mirror back to your face. Do you agree with my belief? I'm not asking you how much light was reflected, or how much interference there was, or the angle of reflection. I'm asking merely for your interpretation of the factual experience you just had: Did light from the lamp reflect off your face onto the mirror and back onto your face? Yes or no?
    0 0

Prev  1  2  3  4  5  6  Next

You need to be logged in to post a comment. Login via the left margin or if you're new, register here.


The Consensus Project Website

THE ESCALATOR

(free to republish)


© Copyright 2024 John Cook
Home | Translations | About Us | Privacy | Contact Us