Average global temperature

Discussion in 'Earth Science' started by vhawk, Mar 2, 2009.

  1. Trippy ALEA IACTA EST Staff Member

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    But that's not what you actually said though is it, you said you respond to every post in its entirety, something that blatantly isn't true, because i've seen you skip past points and not address them.

    And more to the point, you keep missing things.

    Round and round the Mulberry bush...

    You just don't stop do you? You're like a chihuahuah with a bone.
    You stated (essentially) that because I presented Monckton and Beck, that I must agree with them. I pointed out that to some extent Monckton and Beck represent the other side of the story.
    This BS you're spouting is precisely that.

    Total and utter crap.
    Every time except the first I have referred back to what Gore said, and what you claimed Gore said: "That’s why the citizens of these pacific nations had all had to evacuate to New Zealand".

    Or are you now denying that he said even this, even though it's right there in the transcript.

    And I notice that in spite of all of your hot air and testiculation, you have yet to prove how anything I have said differs substantially from this (or for that matter differs at all from this).
     
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  3. iceaura Valued Senior Member

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    !? Now I don't know where to begin - that shit isn't even close.

    Here's something I did say, that will do as a response from now on probably:
     
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  5. Buffalo Roam Registered Senior Member

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    I guess that I stated that wrong, I agree with you about the eccentricity in the Milankovitch Cycles and the 6% variation.

    Yes, I was commenting on ALGORE and His insistence on only His interpretation of Global Warming and the correct actions to the problem and that man actually can take corrective action to the problem.

    What I see is that we don't know if there actually is a true case of Global Warming going on, if anthropomorphic action is the cause, or if is all a natural cycle.

    ALGORE is advocating action only on the Idea that "We must do something now", with out knowing if those actions are a solution or will just exacerbate the problem, or if there is a problem at all.

    If this can happen as fast as ALGORE and His minions claim, the wrong actions could be even more damaging than doing nothing at all.

    So let find out what the actual situation is and what we really can do about it if anything at all.

    Exactly, but what are those "one thing or another" are they anthropomorphic, or natural source, because of warming from the Malinkovitch Cycles, I would tend to think that the Tundra's of Earth have a large sink of CO2 and potential source of CH4, plus the massive amounts of CO2 and methane from the natural cycles of the oceans, the flora and fauna, as it lives-breathes-dies-and decays, the vents, volcanic actions, and other thing I don't exactly remember right now, (Old Fart Milankovitch moment)


    Thank you.


    Sorry again I may have stated this wrong, I was talking about the Malinkovitch Cycle here, but in other post I have tried to address and bring into the debate, the Sun Spot Cycles, The natural Ocean Cycles, Volcanic Activity, ocean and land based sites.

    Don't doubt that I have brought up many different things that I believe are far more responsible for any perceived warming, than anything man can create.

    It is not just one cycle that is responsible, as the universe is nothing but interlocking cycles, gravity influences probably being the biggest driver of those cycles.

    To me the Two biggest things responsible for what is called Global Warming,

    1. Gravity, as shown by the Milankovitch Cycles, and there effect on the Orbital Aspects, Eccentricity, Precession, Obliquity, which then effects the solar forcing, and then the Statges of Glaciation.

    2. The Sun it's self, as the Source of all energy that make life possible on this Planet, no Sun no life. And until we can control the output of the Sun, I doubt that there is anything we can do on earth that will have any effect on the warming and cooling of the earth.

    Those two factors affect percentages changes in our environment, which will have effects to our environment that we can do nothing to affect.

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    My main concern is that if we can affect this, that we do what is effective, and the most effective corrective action, but as of today we don't know if this is Anthropomorphic, or Natural Environment.
     
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  7. Trippy ALEA IACTA EST Staff Member

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    I understood what you were saying, however, my point was that if we assume that the cooling trend you observed is real, and that the Milankovich cycles are responsible for it, then there should be a corresponding trend in the total global irradiance, as that is how the milankovic cycles affect the climate, there is however, no such clear trend (the point of the graphs that I produced) therefore if we assume the cooling trend you have noted is a real downturn in average temperatures, then the Milankovich cycles can not be responsible.
     
  8. Trippy ALEA IACTA EST Staff Member

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    Whatever.

    I can site all three things happening, i'm just not going to because I already know how that conversation will ends - you denying it, we've been down that garden path.

    You keep making stupid comments.

    Each and every time I've paraphrased Al Gore (except, I believe the first) I've also included or referred back to the text of the original quote from the transcript you provided, so your excuse that I keep making stuff up doesn't wash.

    I'm done with this conversation.

    My original point still stands, and it stands unchallenged (the point you contested wasn't the point that I was making) and that is that Taking the wrong (corrective) action is potentially more disasterous then waiting a little while and taking the appropriate corrective action.

    I've specifically stated that when I make this comment I'm considering some of the big geo-engineering projects which could take as long to correct, and be more expensive then delaying and making a correct action.

    I'm also fairly certain that I've explicitly stated that I do not consider reducing carbon emissions under the same umbrella, because carbon emissions can always be cranked back up pretty damn quickly should it become neccessary.
     
  9. Buffalo Roam Registered Senior Member

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    But, what about the Obliquity of the Ecliptic/Axial Tilt? added to that the drop in sunspot activity?

    Now from my reading, am I correct that we should be somewhere at the peak or just past it, in minimum Orbital eccentricity, and moving into the (I think this is the right word for what I am asking) ellipse?

    I know that it will not be something readily apparent for several centuries, but we should be starting moving into a orbit cycle that leads to the next ice age.

    You are making me think, I think I see what you are saying.

    Some times I can't quite find the right word for what I am trying to say, I can see it in my head, but having trouble putting it into words.

    Something else, when you reach the turn over in the cycle, and on the cosmic scale that this is;

    At the peak, is it possible that the swings between peaks warm and cold are natural, and as we move deeper into this part of the Milankovitch Cycles, the trend to cooling will steady out to consistent trend, with out the swings.

    That is what I think I am am seeing in the information I am reading, we are at the peak of the concentric orbit, or just past it, and putting all the part of the Milankovitch Cycles and Sunspot Cycles, and the Ocean Currents and their cycles, and the Gravitational influences, that we are in for a period of Global swings in temperatures and weather activity until we are far enough into the cycle's aphelion?

    And even today, the Perihelion and Aphelion of the Orbit, is only 3.4% and the difference between Perihelion and Aphelion is only 6.8%, but at the Perihelion, there is 23% more energy reaching the earth.

    So as we move into the Aphelion of the orbit those numbers will only increase, and a natural cooling will take place, and nothing we can do, unless we can increase the out put of the Sun is going to stop the cooling.

    I am getting a picture that man if He has any responsibility in this, is the most minimal of factors, Gravitational forces on a solar scale, Sun, and natural sources, released because of solar heating, all of which drive the ocean cycles, and melts the carbon sinks in the Tundras, are the major factor here, and until man can control any one of these forces, we are just along for the ride, unless we can get off the planet, by the next ice age.
     
  10. Trippy ALEA IACTA EST Staff Member

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    But i'm talking about solar irradiance (insolation) not solar activity.
    Insolation is how much energy is recieved at the surface, and so it varies in response to solar activity (increasing solar activity -> Increasing numbers of flaculae -> increasing total insolation) as well as the Milankovich cycles.

    Pretty much, yup.

    Pretty much, yup, and according to the grpahs that I've seen (i'll see if I can rustle them up again when I get home) this won't start to have a cooling effect until some time in the next couple of thousand or so years (i've seen one paper that suggested that if we cut out carbon emissions back to a specific level, with a few well timed injections of cabon into the atmosphere, we could potentially forestall the next ice age for another 500,000 years).

    I'm doing my job then, I'm glad someone appreciates it.

    I know the feeling.

    That seems to be the general mainstream consensus, yes, and seems to be backed up by the data - that once a certain point is reached, the climate becomes increasingly chaotic, until another stable phase is reached (an analogy would be spring weather).

    Eccentric, not concentric.
    Eggs are eccentric, ripples in a pond from a stone throw are concentric.
    More or less.
    The cycle doesn't have an aphelion. Aphelion literaly means 'furtherst from the sun' it's greek (I think), but yes, if we look at the various cycles we see minima and maxima, and the current thinking seems to be that the minima and maxima, the transitions from one trend to another, are associated with chaotic climate behaviour.

    Sounds about right, although I lack the will power to verify those numbers at this time.

    Not quite, if we accept that Carbon dioxide is a greenhouse gas, then elevating the levels of carbon dioxide will raise the average temperature of the earths surface (remember assuming that the rise in CO2 levels lags the rise in temperature, this doesn't rule out the role of carbon dioxide as a greenhouse gas).

    We may not be able to increas the output of the sun, but we can increase the amount of heat energy retained by the earth - but doing so would be one of those geoengineering projects I keep talking about.

    I don't know that I neccessarily agree with this statement, yes there are other climate forcings in play, however the physical properties of the atmosphere are governed by it's chemical composition, and we are in the process of altering that composition. This is the closest thing that youw ill find me to voicing my own opinion. You're on the right track here, but the other thing to bear in mind is that least significant is not the same as insignificant.
     
  11. Buffalo Roam Registered Senior Member

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    Question, Saturn and Jupiter have large gravitational affect on the sun, and its tidal actions, and that affects the Sunspot Cycles, what do those same gravitational forces do to our planet?

    I know the Moon exerts the strongest gravitational force on our oceans, but how do the gravitational forces of the rest of the planets figure into this mix, and what is their effect on our warming and cooling as they should have a effect on the La Nino, La Ninia, and the Gulf Stream Current, which affect our weather cycles, cooling and warming.

    I know there are more ocean currents that operate in this type of cycle, but those are the ones I have heard the most about.

    Now what about the Invariable Plane?

    Trippy, did I pull a good one, I was reading the graph left to right instead of right to left.

    I am used to seeing the "now" on the right side of the graphs.

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    But then I read this:

    The future

    Since orbital variations are predictable[8], if one has a model that relates orbital variations to climate, it is possible to run such a model forward to "predict" future climate. Two caveats are necessary: that anthropogenic effects and that the mechanism by which orbital forcing influences climate is not well understood.

    An often-cited 1980 study by Imbrie and Imbrie determined that, "Ignoring anthropogenic and other possible sources of variation acting at frequencies higher than one cycle per 19,000 years, this model predicts that the long-term cooling trend which began some 6,000 years ago will continue for the next 23,000 years."[9]
    More recent work by Berger and Loutre suggests that the current warm climate may last another 50,000 years.
     
    Last edited: Mar 10, 2009
  12. vhawk Registered Member

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    101

    well , you chaps are all obviously frightfully clever and i hope my naive question has not caused chums to fall out- it's all to complicate for a poor old fiool like me who can't even do sums as we call them in England either the world will drry out to a crispor flood- I don't know but most people seem pretty convinced and jump on me if I doubt AGW I doubt if the sea will rise as high as Devizes in Wiltshire where I dwell
     
  13. Buffalo Roam Registered Senior Member

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    16,931
    Again, I made a assumption of understanding, and didn't explain my thoughts fully, I should have said that we are at the most concentric orbit of the eccentricity of the Malinkovitch Orbital Cycle, which accounts for the low variation in the Insolation.

    Yes, the orbit of the earth has the Aphelion, and a Perihelion, not the Milankovitch Cycle, bow that clears up some of my confusion of statement.

    But my question is that CO2 lags behind the warming cycle, and as the levels of CO2 peak, cooling appears to occur, so from what I am reading and see, could it be Possible for CO2 to be a Ice House Gas, not a Green House Gas?

    The Ice Core samples show a lag in CO2 and CO2 increase to a maximum, not sure where that point is, the turnover takes place and cooling occurs, and the CO2 again lags the cooling until we reach the bottom of the cycle and CO2 and CH4 are again locked in the carbon sinks, of bottom ocean ice and tundra.

    http://www-odp.tamu.edu/publications/199_SR/synth/synth_7.htm

    I am getting a picture in my head, that with out CO2 that warming cycles would be much more sever, that CO2 just might be a damper on warming, and that once it attains a catch up point to the warming, it causes the change over to the next cooling cycle, along with the other cycles, and is the forcing of the cooling?

    ??????????

    Prehistoric global cooling caused by CO2, research finds
    Feb 26, 2009 ... "Previous reconstructions gave no evidence of high-latitude cooling," ... How Earth's temperature changed during this climate transition ...

    news.uns.purdue.edu/x/2009a/090226HuberPete.html - 13k - Similar pages
     
    Last edited: Mar 10, 2009
  14. Trippy ALEA IACTA EST Staff Member

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    I understand what you mean, but i'm not sure that it's correct to refer use concentric in this context (it could be) least eccentric or most circular are the phrases i've usually seen used to describe it.

    Glad to be of service.

    The short answer is no, I'll try and explain more later.

    Essentially, greenhouse gasses are so called because they have the property that they absorb strongly in the infra-red part of the spectrum. This absorbed radiation is converted into thermal energy, and eventually released again as infra red radiation of (I think) the same wavelength. This means that, roughly speaking about half of the radiation that the carbon dioxide absorbs, that would ordinarily have been radiated back into space, is emitted downards, back to the ground. Some of this will be absorbed by other carbon dioxide molecules, heating the atmosphere, and some of it will be absorbed by the ground, heating the ground.

    This website has some good information on the physics behind what happens, and shows a spectrum of sunlight passed through carbon dioxide.

    The graph below:

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    Is courtosey of the TPF Book
    It shows the thermal spectrum of earth as seen from space. The red line is the ideal blackbody curve, the purple one is the measured spectrum.
    Here is the same for Carbon Dioxide:

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    And Water:

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    Linked is Methane: http://tpf.jpl.nasa.gov/library/tpf_book/gallery/images/4-6-ch4.jpg

    The importance of a gas as a greenhouse gas is based on the location of the absorption feature in the spectrum, and the strength of the absorption feature.

    The thing about gasses as they obey this thing called Henry's Law.
    One of the consequences of this is that as the partial pressure of the gas in the atmosphere - essentially it's concentration increases, so does the solubility of that gas in water, but, as the temperature decreases the solubility of the gas increases.

    This article talks about the Carbonate Compensation Depth. Essentially, what that means, is if you drop a sea shell into the Marianas trench, it will fall, above a certain depth, the calcium carbonate is insoluble, but, the solubility of the calcium carbonate varies in a predictable way with depth, pressure, and the concentration of CO2 in the water (which in turn depends on the Temperature, and the partial pressure of atmospheric CO2).

    The reason that it depends on the CO2 is that when calcium carbonate dissolves in water the following occurs:

    \(CaCO_3 \rightleftharpoons Ca^{2+} + CO_3^{2-}\)
    The Carbonate then reacts with water thusly:
    \(CO_3^{-2} + H_3O^+ \rightleftharpoons HCO_3^- + H_2O\)
    However, when we dissolve Carbondioxide in water, this also sets up an equilibrium reaction in the water:
    \(CO_2 + 2H_2O \rightleftharpoons HCO_3^- + H_3O^+\)
    These to sets of equations work in synergy to give:
    \(CaCO_3 + CO_2 + H_2O \rightleftharpoons Ca^{2+} + 2HCO_3^-\)

    Anyway, the CCD represents the depth in the ocean at which the rate at which calcium carbonate is dropped from above is equal to the rate at which it dissolves, below this depth, no calcium carbonate is preserved as deposits on the sea floor.

    Now, if I've remembered everything correctly (this is third year environmental chemistry we're talking about at the moment).

    Increasing the amount of carbon dioxide in the atmosphere increases the amount of carbon dioxide in the oceans, which raises the level of the CCD (assuming the temperature remains constant).

    Lowering the temperature of the oceans increases the solubility of calcium carbonate in the water which raises the level of the CCD (assuming the concentration of carbondioxide in the water stays constant).

    However, lowering the temperature of the ocean also increases the solubility of carbondioxide in the water, which increases the concentration of carbondioxide in the water, which adds to the lowering of the CCD.

    So, in a situation where you have rising temperatures, and constant pp CO2 in the atmosphere, the CCD would lower (it would become deeper).
    In a situation where you have a rising pp CO2 in the atmosphere, but a constant temperature, the CCD would also lower.

    But, in a situation where you have, for example, a rising pp CO2 and a rising temperature, whether the CCD rises or lowers depends on which effect is more important, and it may well be that there is some threshold level (as there often is with opposing trends) where first you see the CCD lowering, and then rising (or vice versa).

    I hope that's helpful, I think I have a couple of more things I want to say, but just at the moment I lack time.

    As I said, this is third year environmental chemistry we're talking about at the moment.
     
    Last edited: Mar 10, 2009
  15. iceaura Valued Senior Member

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    24,092
    As the deep water of the ocean changes slowly over centuries under the very light influence of thin air miles above it

    (at least, such is the traditional view)

    perhaps a mention of the effects of CO2 boosting on more shallow and surface water (temperature and chemistry)? The stuff we'll be dealing with over the next couple of generations.
     
  16. Trippy ALEA IACTA EST Staff Member

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    This isnt quite accurate.
    The shallow water is pretty much in dynamic equilibrium with atmosphere, I don't recall off the top of my head what depth this extends to.

    There is also an equilibrium that exists between the deep water and the shallow water, but this is more sort of a diffusion gradient then anything else, it's slow, and it depends on things like the CCD.

    where the deep water really comes into play is where it up wells. I think the deep water is about 10-12,000 years old (or some such) and so was in equilibrium with the atmosphereic composition at that time, so it's cold, it's dissolved CO2 may have been boosted by increased carbonate production at the surface, however, it still likely to be below equilibrium, meaning that areas that experience an upwelling of cold deep water (for example, the indian ocean, the north pacific ocean, off the coast of South America) can potentially act as a CO2 sponge (I think this has been verified by atmospheric measurements).

    One of the things that concerns me personally is that assuming we're correct, and assuming we manage to do something about it and lower CO2 levels in the short term, what happens when the current CO2 rich (as it will be by this time) surface water that's being turned into deep water begins welling back up to the surface - it will no longer be in equilibrium, the water will degas until it acheives a stable equilibrium, and there will be nothing that we can do about the rising CO2 levels.

    I have the same concern about seeding the oceans with plankton.

    Cliff notes: An increase in carbonate deposition. Potentially if the temperature of the surface waters rises far enough fast enough (unlikely currently, but if the Kyoto protocol is ratified and successfully implemented, then it becomes more of a possibility, however I lack the time to do the calculations, but if it's in the 10's (for example)of degrees then it won't happen), there will be pH changes and other stuff.

    I'll go into more detail when I get home from work tonight.
     
  17. Buffalo Roam Registered Senior Member

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    Traditional view? Thin Air miles above it, Now take a look at Thermohaline Circulation, the moon and it's tidal effects, thin air?

    http://biology.fullerton.edu/biol317/ch/ch02.html

    There is something far more prevelent and promotes far more boosting of global warming than CO2, it is the partial pressure of water vapor in a parcel of air to the saturated vapor pressure of water vapor at a prescribed temperature, it is a absolute positive feedback gas.

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    That ratio can be given as:

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    Mixing ratio can also be expressed with the partial pressure of water vapor:

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  18. iceaura Valued Senior Member

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    Well, as has been noted:
    and confirmed:
    we have a long time to worry about that. Maybe it will bail us out of an ice age, a wonderful gift from the Time of Ancestral Immolation.

    If in fact the deep water is that isolated, as is traditionally presumed.
    The heat trapping from the CO2 boost is feared to have a large boosting effect on the average water vapor capacity and content of the air, and be amplified thereby - that is possibly the major worry, among the dozens, of the CO2 boost.
     
  19. Trippy ALEA IACTA EST Staff Member

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    10,890
    First off, I find your statement "As the deep water of the ocean changes slowly over centuries under the very light influence of thin air miles above it" misleading. To me at least (which means it's probably not just me) it seems to imply that the chemistry of deep ocean water is influenced by the chemistry of the atmospher. It isn't. There's a bunch of factors such as the thermoclines, haloclines, and perhaps the lysocline that mean that vertical mixing of the oceans is non existent (or very close to it).

    This tends to be backed up when one examines the physico-chemical properties of deep ocean water versus shallow ocean water, as well as isotopic analysis.

    What I was saying is that the age of the deep water in the ocean varies from about 400 years (or 200-500 according to other sources) in the atlantic, to 1600 (or 1000-2000 according to other sources) years in the pacific (Broecker, W. S., M. Andree, G. Bonani, W. Wolfli, H. Oeschger, M. Klas, A. Mix, and W. Curry (1988), Preliminary Estimates for the Radiocarbon Age of Deep Water in the Glacial Ocean, Paleoceanography, 3(6), 659–669).
    This means that the deep water in the atlantic ocean (depending on whee you look) is in equilibrium with the atmosphere as it was 400 years ago, and in the pacific 1600 years ago.

    The implication of this is that possibly in as little as 50 years the water that was at equilibrium with the atmosphere at the beginning of the Industrial age is going to start welling up to the surface in the atlantic ocean, and possibly in as little as 200 years water that is in equilibrium with the atmosphere now will well up.

    So no, not a beneficial gift that will benefit our children and help stave off an ice age.
     
  20. Buffalo Roam Registered Senior Member

    Messages:
    16,931
    For nearly 30 years, Professor Christy has been in charge of NASA's eight weather satellites that take more than 300,000 temperature readings daily around the globe. In a paper co-written with Dr. Douglass, he concludes that while manmade emissions may be having a slight impact, "variations in global temperatures since 1978 ... cannot be attributed to carbon dioxide."

    Moreover, while the chart below was not produced by Douglass and Christy, it was produced using their data and it clearly shows that in the past four years -- the period corresponding to reduced solar activity -- all of the rise in global temperatures since 1979 has disappeared.

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  21. iceaura Valued Senior Member

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    As has been noted repeatedly by various alarmists, the influence of CO2 heat trapping on both water vapor concentration and partial water vapor pressure is one of the more worrisome possiblities of the CO2 boost.

    The generally increasing density for its contribution to further heat trapping, the geographically critical (in, say, Australia) decreasing vapor pressure for its drying effect on plants and fresh water bodies (among other and varied influences).
     
    Last edited: Mar 23, 2009
  22. vhawk Registered Member

    Messages:
    101
    then why do so-called scientist keep saying that the average global temperature is x or y or is going up? I thought scientist were supposed to be precise in their language or use a suitable caveat, never once have i heard one say mind you it all depends on how you define average global temperature or where or when you measure it. I thought only a system in stasis could have an average temperature but maybe I did not mean stasis
     
  23. iceaura Valued Senior Member

    Messages:
    24,092
    By choosing an appropriate time scale (a year works pretty well, because it matches critical agricultural and ecological cycles), agreeing on one of the generally informative and stable methods of calculating the average, and comparing averages calculated the same way in each cycle -

    so each year the average is calculated by the same method as last year, and these averages can be compared.

    For example, the temperature at Mitch's Weather Station can be recorded every five minutes, an agreed average temperature per minute, hour, day, week, month, year, etc, calculated (by fitting curves and numerically integrating, by simply taking the arithmetic mean of the readings, by one or more of several standard methods agreed upon in advance), and after many years we can go back and look at these averages and see patterns. It's cold in January at Mitch's Weather Station, we observe, and we can put an exact number on it by calculating the monthly average temperature reading for several Januaries and comparing them with each other and with August's averages.

    Now if somebody wants to know the average temperature at Mitch's Weather Station, there are several possible answers - the 24hr average calculated by numerical integration under fitted curves will not quite match the arithmetic mean of the temperatures taken at hourly intervals, for example. And the motive of the questioner will help select the appropriate calculation method - the questioner might be more interested in the chances of frost or bolting for estimating seed planting time, say, and so the numerical integration might mislead by concealing spikes. But that does not make the entire concept of an average temperature at Mitch's worthless - if I tell you that the 24 hour average is below 0C for the month of January, you have acquired meaningful information.

    And if we look at a graph of the average temperature for the year over a thirty year run, calculated by a method appropriate for our questions, and see a trend, we can tell people about that.
     
    Last edited: Mar 23, 2009

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