My temperature data analysis

Discussion in 'Earth Science' started by Zeno, Dec 17, 2013.

  1. Zeno Registered Senior Member

    Messages:
    239
    I decided to do my own test to see whether global warming is really occurring. I went to the website http://www.wunderground.com. Once there you can look at temperature records of weather stations. You can see for example in what year the high temperature record was set for say, January 1 at Salt Lake City, Utah. An idea occurred to me that I could use this information to see if it really is getting hotter. So what I did was I took the average of the years that the high temperature record was set for all 365 days at 30 different weather stations. I then compared this average with what the average 'should' be given that the Earth's temperature is remaining the same. For example, for Salt Lake City, Utah the max temperature for January 1 was set in 1997, January 2 was set in 1997, January 3 was set in 1934 and so on... I added up all the years and divided by 365 to get the average. If the Earth's temperature is unchanging, each year in the temperature record has an equal probability of holding the temperature record, so the average should be close to ((n+1)/2) where n is the number of years in the temperature record. A simple way of getting the same thing is ((first year + last year)/2). Nothing says how long they have have been keeping temperature records, so I went with the oldest year I could find that was holding a record. If the average is more recent than what it should be, that indicates some kind of warming trend. Conversely, if the average is further in the past then that indicates some kind of cooling trend. I tried to learn a little bit of statistics in order to see whether my results were significant or not. The years are in a uniform distribution so the standard deviation is equal to ((n^2-1)/12)^0.5. The oldest records from the weather stations in my sample are from 1871. That's 143 years of weather records. The standard deviation is about 41.2. We have from the central limit theorem (41.2/(365)^0.5) or about 2.15. So if the average is more than about 6 years away or about 3 standard deviations from what is expected, that is significant. Anyways, here's a summary of my results, ordered by difference from the expected mean.

    Station ID, City, Year when records began, expected average, actual average, difference, what it means
    Code:
    KSLC  Salt Lake City, UT       1875         1944         1967.03       23.03       significant warming
    KPHX  Pheonix, AZ              1895         1954         1975.05       21.05       significant warming 
    KMIA  Miami, FL                1895         1954         1973.96       19.96       significant warming
    KHOU  Houston, TX              1889         1951         1969.14       18.14       significant warming
    KNYC  New York, NY             1871         1942         1958.64       16.64       significant warming
    KMEM  Memphis, TN              1875         1944         1960.28       16.28       significant warming
    KDCA  Washington, DC           1872         1942.5       1955.02       12.52       significant warming 
    KSAN  San Diego, CA            1874         1943.5       1955.78       12.28       significant warming
    KSTL  St. Louis, MO            1874         1943.5       1955.28       11.78       significant warming
    KCQT  Los Angeles, CA          1878         1945.5       1956.82       11.32       significant warming
    KTLH  Tallahassee, FL          1894         1953.5       1964.54       11.04       significant warming
    KRDU  Raleigh, NC              1887         1950         1960.71       10.71       significant warming
    KMKE  Milwaukee, WI            1871         1942         1952.08       10.08       significant warming
    KSFO  San Francisco, CA        1928         1970.5       1980.57       10.07       significant warming
    KBOS  Boston, MA               1872         1942.5       1951.41       8.91        significant warming
    KPVD  Providence, RI           1904         1958.5       1966.67       8.17        significant warming
    KIND  Indianapolis, IN         1871         1942         1948.55       6.55        significant warming
    KLBB  Lubbock,  TX             1911         1962         1968.42       6.42        significant warming
    KPIH  Pocatello, ID            1935         1974         1980          6           warming
    KOKC  Oklahoma City, OK        1891         1952         1957.41       5.41        some warming
    KCMH  Columbus, OH             1879         1946         1950.25       4.25        close to average
    KPDX  Portland, OR             1940         1976.5       1979.5        3           close to average
    KBHM  Birmingham,  AL          1895         1954         1954.02       .02         close to average
    KMSO  Missoula,  MT            1893         1953         1952.66       -0.34       close to average 
    KMDW  Chicago, IL              1928         1970.5       1968.85       -1.65       close to average
    KCLS  Chehalis, WA             1948         1980.5       1978.54       -1.96       close to average
    KDET  Detroit, MI              1948         1980.5       1976.61       -3.89       close to average
    KLAS  Las Vegas, NV            1937         1975         1968.27       -6.73       significant cooling
    KRVS  Tulsa, OK                1905         1959         1950.88       -8.12       significant cooling
    KGSO  Greensboro, NC           1899         1956         1946.66       -9.34       significant cooling
    
    So, is it getting warmer? The answer appears to be....YES!
     
  2. Google AdSense Guest Advertisement



    to hide all adverts.
  3. Peregrine Registered Member

    Messages:
    90
    You are using faulty statistics.

    Yes, the Earth is warming both naturally (I will elaborate) and anthropogenically. However, you're data set does not go back far enough to be statistically sound.

    First lets address your data set. You are exprapolating from weather logs to prove global temperature. Bad statistical analysis.

    Luckily, statistical analysis has been done for you:

    View attachment 6791
    from: http://hyperphysics.phy-astr.gsu.edu/hbase/thermo/temp20.html
    View attachment 6792



    Now, if you look at an even further into the past...

    View attachment 6793

    From: http://ocw.mit.edu/courses/earth-at...-2011/lecture-notes/MIT12_009S11_lec12_16.pdf



    And if you look even further into the past:

    View attachment 6794

    From: http://www.nc-climate.ncsu.edu/climate/climate_change



    Now, there are a couple of factors current to the climate debate....


    1. Mpemba Effect http://hyperphysics.phy-astr.gsu.edu/hbase/thermo/hques2.html#c3

    2. 10, 100, 1000 year natural climate cycles (im rounding) View attachment 6795

    3. Biological Reaction to CO2


    It has been proven that CO2 acts as a 'blanket.' It has been proven that CO2 additionally warms the planet. What is being studied currently is how the Earth reacts to additional CO2.

    Regardless, your data set is irrelevant.
     
  4. Google AdSense Guest Advertisement



    to hide all adverts.
  5. Zeno Registered Senior Member

    Messages:
    239
    Really? Back to the 1800s isn't far enough?

    The data set comprises quite a large area over a long period of time.
    My data set takes into account 3,456 years of temperature records, or 1,261,440 days of temperature records.
    That's not enough to make some kind of sound statistical conclusions?
    Although, you may be right. A large number of high temperature records in the U.S. were set in the 1930s.
    Global warming skeptics often use that to indicate the planet is not warming.
     
  6. Google AdSense Guest Advertisement



    to hide all adverts.

Share This Page