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  1. #1
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    GLOBAL WARMING: Or not...

    Warming fastest since dawn of civilization, study shows - Science

    Fastest planetary warming since dawn of civilization - or not...

    A good example of how to mislead with statistics.

    People - look at the chart, to begin with. Look at the Y axis. This Y axis declares that the global avg temp has, for 12,000 years, never strayed outside of a one-degree celsius range. Do you believe that?

    How did they achieve this result given the raw data?

    By various techniques used, they have estimated past global temps. However, obviously they cannot give a decent estimate down to the resolution of one day. So, their analysis could not indicate that July 1 of one year was 1 degree warmer or cooler than July 1 of the previous year.

    The resolution is more broad than that. The estimate for any point in time will thus be equivalent to the average of all time points within their resolution.

    If you calculate your home town's avg March temp across years, you will find that it varies very little. Avg might be, say, 20 degrees celcius, and that 2/3 of months fall within 1 degree C higher or lower.

    That avg technique is fine, but it hides the fact that temps within the resolution time span of one month can vary greatly. A fair amt of days within March might be from 15 to 25 celsius.

    They usually calculate these things with a "running avg," also. So, the data point for "March" retrospectively might be the value of seven months around and including March for that yr, so the avg of Dec-Jun.

    This is a representative, robust estimate when the more fine resolution is not quite needed, and you are using a bunch of proxies and want to do a lot of averaging and combining to tamp down the various errors here and there.

    This running-average strategy is often described as a "filter." It "filters" out highs and lows occurring within the time frame described. They are not actually "gone" like the air filter in my A/C takes dust out of the air going into the A/C. The data are still there, just tamped down by averaging, and by running-averaging.

    Here, they have "filtered" the data at a resolution greater than 100 years. This serves to totally flatten out highs and lows, including the Medieval Warming Period, the Minoan Warming Period, and the Roman Warming Period, ALL of which are estimated to have been warmer than the present day.

    The farther back in time you go, the more you have to be satisfied with filtering to make fairly confident, although blunt, estimates.

    This filtering has not been aplied to the modern era. We have daily thermometer readings from the 1600s, then more accurate and verified from the recent century, and then satellite data minute by minute in the recent 30 years.

    So, the highs and lows are not filtered out of the recent part of the temp record, but they are filtered out of the estimates of the past.

    If you go to Climate4you
    climate4you welcome
    Then select "Global Temperatures" from the sidebar on the left,
    Then select
    "Estimates of recent global air temperature change"
    From the list at the top, it will take you to a few global-temp data sets.
    They are black-and-white figures with a blue line for the temp.

    They all use 13-month running average or something very similar. You can read the note. You will see that the more bold average line does not go up to the most recent data point - that is because the current month has only had its previous months to contribute to the 13-month window;
    of the months to either side, the remaining months have yet to happen.
    So, on a 13-month running avg, the most up-to-date avg will be 6 months ago.

    This visually shows you how the "filter," at whatever resolution, hides peaks and valleys.

    The global warming skeptics dig into the data and think things thru.
    The warming fans take a picture like in this news story and get panicked.

    I hope this helps some of you true believer to understand how some of us who are skeptical have arrived at the healthy skepticism.

    It takes a bit of digging into the data. I hope my explanation makes sense.


    MODERATOR'S NOTE: I have edited the title to conform with the Style Guide.

  2. #2
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    So when was the fastest warming since the end of the last ice age (at least that is what I think this study claims based on a summary I read, dawn of civilization would be lesser portion of that time)?

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    From the climate4u site.

    Central England air temperature since 1659


    Seems to show pretty constant temps since 1659. There are peaks and valleys to the 11 year rolling average, but nothing outstanding. From 1980 to 2010 there looks to be peak, but it also appears to be dropping a bit. Looks like just another of the many peaks and valleys in the data.
    Joe
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    I wouldn't pretend to be knowledgeable about this topic but I'm pretty sure you can't pick any one place and talk about global changes. At least that is my impression, I'm pretty sure I've even seen where some places might be trending colder despite a global warming?

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    fastest warming based on 'reconstructions' of temp before thermometers or interweb:

    GLOBAL WARMING:  Or not...-globaltempsinceiceage01.jpg
    Quote Originally Posted by Dwayne Barry View Post
    So when was the fastest warming since the end of the last ice age (at least that is what I think this study claims based on a summary I read, dawn of civilization would be lesser portion of that time)?
    From 'climate4you' here is estimated temps since the last gen-u-wine ice age.

    The recent warming tend of the recent 100 years or so is evident.
    To consider the claim that the current is the most rapid, you would look for other increases of similar duration of time [horiz] and at least as steep [rise over run].

    Unfortunately, this graph barely has the resolution to compare this.
    However, you can certainly eyeball-locate several spans of time where the steepness of the rising line was at least as steep, and some where it is steeper - due to resolution, looks straight vertical.

  6. #6
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    Quote Originally Posted by Dwayne Barry View Post
    I'm pretty sure you can't pick any one place and talk about global changes.
    Yep. To borrow from the OP, that's a "good example of how to mislead with statistics."
    Quote Originally Posted by Dwayne Barry View Post
    I'm pretty sure I've even seen where some places might be trending colder despite a global warming?
    Some may be getting colder not despite, but because of global warming

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    Quote Originally Posted by PJay View Post
    To consider the claim that the current is the most rapid, you would look for other increases of similar duration of time [horiz] and at least as steep [rise over run].

    Unfortunately, this graph barely has the resolution to compare this.
    However, you can certainly eyeball-locate several spans of time where the steepness of the rising line was at least as steep, and some where it is steeper - due to resolution, looks straight vertical.
    To consider the claim you have to look at global temperatures, since that is what the claim is about

  8. #8
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    Words can't stop it.
    We're letting a couple hundred billionaires scam us.

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    Quote Originally Posted by Dwayne Barry View Post
    I wouldn't pretend to be knowledgeable about this topic but I'm pretty sure you can't pick any one place and talk about global changes. At least that is my impression, I'm pretty sure I've even seen where some places might be trending colder despite a global warming?
    that is true to a point, but it does show long term data.


    Here is mid term data on global temps.

    What you see is warming trend from 1990, but a it is the same rate as 1925 to 1950.

    Data from 1979 to today might be more accurate globally, but it lacks the time duration to give it meaning. What you can see from the England data cycles that extent over 20-40 years. Temp goes up and goes down naturally.


    I have yet to see temperature date that can separate out temperature changes caused be normal cycles and or natural special cause (ie volcano) from anything created by man.
    Joe
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    Quote Originally Posted by Dwayne Barry View Post
    I wouldn't pretend to be knowledgeable about this topic but I'm pretty sure you can't pick any one place and talk about global changes. At least that is my impression, I'm pretty sure I've even seen where some places might be trending colder despite a global warming?
    The suspicious thing is that it is really difficult to find any place where temps are notably rising or falling to a degree [no pun intended] that would raise an eyebrow.

    You can explore this by going to "WolframAlpha," and asking it to provide a chart with average temps for the city of your choice.

    Even with this, confounded by "urban heat index," where local urban growth bumps the temp up for a relatively small portion of our geography, it is hard to find any examples of this runaway global warming.

    Try some U.S cities, then some international cities.

    Website:
    Wolfram|Alpha: Computational Knowledge Engine


    Follow this query format:
    average temperature Stratford-On-Avon past 80 years

    Enter however many years past you want - but it will gack if the data are not available - if so, then decrease the number of years, i.e., instead of past 100 years, ask for past 60 years.

    Enter the town: you can enter Memphis Tennessee or Memphis Egypt if you want.

    Now, play "Spot the Global Warming." Good luck. I tried, and barely could find a city with anything more than a degree over these time spans. That is within the error band, and within the confound of urban heat index.

  11. #11
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    Quote Originally Posted by PJay View Post
    Click image for larger version. 

Name:	GlobalTempSinceIceAge01.jpg 
Views:	37 
Size:	100.0 KB 
ID:	276896

    From 'climate4you' here is estimated temps since the last gen-u-wine ice age.

    The recent warming tend of the recent 100 years or so is evident.
    To consider the claim that the current is the most rapid, you would look for other increases of similar duration of time [horiz] and at least as steep [rise over run].

    Unfortunately, this graph barely has the resolution to compare this.
    However, you can certainly eyeball-locate several spans of time where the steepness of the rising line was at least as steep, and some where it is steeper - due to resolution, looks straight vertical.
    The other thing you have to look at in this chart is the vertical exaggeration. The x axis covers 11,000 years of history, the Y axis only covers 6 degrees of temperature.

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    Quote Originally Posted by JoePAz View Post
    What you see is warming trend from 1990, but a it is the same rate as 1925 to 1950.
    Of course, the plots from 1990 to now include data from 1940 to now. The filter just might be affecting things there

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    Quote Originally Posted by PJay View Post
    Now, play "Spot the Global Warming." Good luck. I tried, and barely could find a city with anything more than a degree over these time spans. That is within the error band, and within the confound of urban heat index.
    Much of the warming occurs closer to the poles. Turns out there aren't many cities there.

    But it's terrible to mislead with 'statistics'

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    On the upside, global temps have not risen over the last 17 years.

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    I didn't realize global warming was being measured and observed in Central England.

    How interesting....
    I hate you all

    j/k lol kthxbye!

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    Unlike in Britain, there has been little publicity in Australia given to recent acknowledgment by peak climate-science bodies in Britain and the US of what has been a 17-year pause in global warming. Britainís Met Office has revised down its forecast for a global temperature rise, predicting no further increase to 2017, which would extend the pause to 21 years.
    Who said this?

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    Quote Originally Posted by TerminatorX91 View Post


    Temp records since 1880 are not conclusive of global trend. It may be they are the warmest on record, but temps rise and fall all the time. England data which is a stream from 300+ years of data shows many temperature cycles. To really understand climate change you need to understand the natural cycles and what part of these cycles we are in. If the cycles are 20-50 years then looking short term data is pointless. Looking at Ice cores from Greenland it appears we colder now that at times in the past, but temps are up short term.

    I believe one thing. Global temps are not constant. They are always changing. What I don't see is data to show man is involved with any of these temperature changes. All temp changes I see fit well with they typical temperature change the earth has seen for many many years.
    Joe
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  19. #19
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    People. You do not observe global warming by sticking your thermometer out the window. Global warming is the global average.
    I hate you all

    j/k lol kthxbye!

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    Quote Originally Posted by foto View Post
    People. You do not observe global warming by sticking your thermometer out the window. Global warming is the global average.
    20-50 years of data is nothing cannot be used to determine natural trends and cycles.

    The problem is how you measure global temps before we record data? We guess? It is like me say we have global warming by looking at temps from Jan to March this year.... You need to understand the cycles if you can understand that I can't help you.
    Joe
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    Quote Originally Posted by coreyb View Post
    Much of the warming occurs closer to the poles. Turns out there aren't many cities there.

    But it's terrible to mislead with 'statistics'
    This is the Global Warming Game. The people that believe in global warming cannot stick to an issue for more than one round of analysis. This is because since there is no global warming, it is pretty easy to debunk each claim.

    so, the global warming true believers have to change the topic.

    case in point: man-the man-made global warming theory predicts the warming ought to be in the troposphere, where the co2 is supposed to absorb radiation energy and radiate it toward the earth, bu tnot let that energy/heat escape back out into space, and the theory says that the "tropics" are supposed to get warm, not the poles.

    However, the troposphere is not behaving according to theory.
    And the tropics are not behaving according to theory.

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    Quote Originally Posted by foto View Post
    People. You do not observe global warming by sticking your thermometer out the window. Global warming is the global average.
    OK: if, overall, the global temps are rising at some alarming rate, then it would not be too difficult to find an example.

    Go ahead, plug away at WolframAlpha. Let us know how that works for you.

    When you find a warming city, enter three or four other cities around it.

    Logic says that you would not find those to be steady-state or cooling, but the simple majority of those nearby cities would have to be rising.

    The rising temps have to be somewheres.

    Where are they?

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    Quote Originally Posted by foto View Post
    I didn't realize global warming was being measured and observed in Central England.

    How interesting....
    Quote Originally Posted by foto View Post
    People. You do not observe global warming by sticking your thermometer out the window. Global warming is the global average.
    What/who are you referring to?

  24. #24
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    Oh, on WolframAlpha -
    if it does not give you the line graph, but instead gives a much mor recent time frame-
    in that "History" box, select "All." --It will thenm give you the entire record for that site.

    I realized this when exploring the Arctic, where all of the warming supposedly is happening.

    Barrow, Tiska Russia, Pevek Russia, Thule Island Greenland, Hammerfest Norway:
    D'oh! D'oh! D'oh! D'oh! and D'oh!

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    Quote Originally Posted by PJay View Post
    This is the Global Warming Game. The people that believe in global warming cannot stick to an issue for more than one round of analysis. This is because since there is no global warming, it is pretty easy to debunk each claim.

    so, the global warming true believers have to change the topic.

    case in point: man-the man-made global warming theory predicts the warming ought to be in the troposphere, where the co2 is supposed to absorb radiation energy and radiate it toward the earth, bu tnot let that energy/heat escape back out into space, and the theory says that the "tropics" are supposed to get warm, not the poles.

    However, the troposphere is not behaving according to theory.
    And the tropics are not behaving according to theory.
    Why do you say that? Because troposphere sounds like tropic?

    Global warming is an indicator of climate change. The actual phenomenon is the changing of the climate, not the temperatures rising everywhere. Some places are getting warmer, some places are getting cooler, some places are getting moister, some places are getting drier, and some places aren't changing much at all.

    Climate change doesn't mean deserts become rain forests, the earth polarity reverses, down becomes up, and Andy Schleck finishes races. There actually isn't a scientific debate as to whether climate change is happening, and whether it correlates with human activity. At this point, there is only scientific debate about the magnitude and cost of the impacts, what we are going to do about it, and society's willingness to pay.

    The only people debating the actual existence of climate change are deceivers, the willfully ignorant, and those that find amusement posting on internet message boards.
    I hate you all

    j/k lol kthxbye!

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