No Warming From CO2

In the never-ending debate over man’s role in increasing global temperatures, carbon dioxide in the atmosphere is claimed by the alarmists to be the culprit responsible for causing unstoppable warming. But is it? What does the temperature record show?

The temperature record is a complicated thing. Zero credibility is given (by many, including me) to the results of the major scientific organizations that purport to monitor the earth’s atmosphere and ocean temperatures, and for many very good reasons. One of those reasons is that the earth is too big, and too varied, and proceeds through too many hourly, daily and seasonal changes, for a global average temperature to have any meaning. Another is the below-mentioned data manipulation, still another is bad locations of measuring instruments. However, it is instructive to observe the temperature record from a single site, especially a site with many decades of temperature readings. Such sites are available to everyone via data published over the internet.

I chose several sites, all small towns in the USA, and examined the temperature records. The data is from the discredited Hadley Research Center’s CRU3 data set. Briefly, the Hadley Center is in England, and is the center of the "Climategate" scandal in which thousands of emails, computer program listings, and other documents were either deliberately leaked or hacked (no one is quite sure which) but in either case were published on the internet in November 2009. As part of Hadley Center’s response, many hundreds of temperature records were published. I downloaded the entire dataset for archiving and my own research purposes. I will refer to the dataset as CRU3.

A word about the discredited CRU3 data. Among the allegations leading to the charge of discredited data include deliberate falsification of data in order to show a warming trend over the last part of the 20^th century. That warming trend is, according to the climate alarmists, due to CO2 placed into the atmosphere by man’s activities, primarily burning coal, oil, and natural gas but also from decomposing garbage in landfills. Even if the datasets are manipulated, and the data shows a warming where there is none, is it possible to find anything worthwhile from examining such datasets? I believe there is, as this article will demonstrate.

The premise that I started with is, if CO2 is responsible for warming the earth, then it should be based on physics and therefore must behave the same, no matter where on earth the behavior occurs. Physics is impartial. As some have expressed it, gravity works no matter where one stands on the earth. CO2, therefore, must cause warming wherever CO2 exists, not just in a few isolated areas. However, CO2 alone is not the cause, according to the climate alarmists. They hold that small increases in CO2 creates additional water vapor in the atmosphere, and that water vapor does the majority of the warming. Still, the effect must be the same in small towns as well as in big cities. Therefore, it will be possible to verify the premise, or falsify the premise, by examining the temperature records for small towns and big cities, all within the same hemisphere and roughly the same latitude. Hemispheres (north and south) have opposite seasons, and different latitudes have great variations in seasons, so those effects can be minimized.

In the CRU3 dataset, folder “72” contains 87 temperature files (or records), all in the USA. Some are large cities, including Miami (FL), Atlanta, San Antonio, El Paso, San Diego, Los Angeles, and San Francisco, among others. Others are small towns, including Ely (NV), Abilene (TX), and Meridian (MS), among many others.

Below in Figure 1 is the temperature record for Abilene, Texas, from 1886 to 2009, approximately 120 years. Abilene is dataset 722660 in the CRU3 dataset. The graph in Figure 1 was produced by copying the data into Microsoft Excel (TM) and performing simple graphing with trendline. The data is the monthly average temperatures for each year, which range roughly from 0 to 32 degrees C. The squiggly white line through the middle is a moving 12-month average. The solid black line through the middle is the linear trend line.

Figure 1

(click on graph for a larger view in a new window)

The overall trend of the temperature data shows essentially zero change, with the actual trend of -0.0019 degrees C per year, or -0.19 degrees C per century. So much for CO2 causing global warming. If any warming were to be occurring, and that warming is due to CO2 in the atmosphere, it must warm the earth equally. Abilene is certainly not isolated, instead, it is on a rolling plain just west of Dallas. Plants grow quite well in Abilene, as the trees, shrubs, grass, and agriculture show quite well. Plants need CO2 to grow.

However, the graph above shows some interesting things when examined in smaller pieces. For example, the climate alarmists claim that the last 25 years, since 1975, warmed at a much higher rate than previous years. Usually, the warmists' mantra is that the latter half of the 20th century was the warmest on record, or for the last 1000 years, or something dire like that. Does the Abilene data show this? I had a look at the 1975 to 2009 data, and the trend is positive, with a slope of 0.031 degrees C per year, or 3.1 degrees per century. Yet, the trend from 1910 to 1940 shows a much higher trend, of 0.045 degrees C per year, or 4.5 degrees per century. Finally, the bit in the center, from 1940 to 1970, shows a distinct cooling trend of -0.0224 degrees C per year, or -2.24 degrees per century.

Well, then, how about the claim that winters are much warmer in the recent 30 years, since 1975, and summers are hotter? No, the Abilene data refutes those claims, too. Winters were clearly warmer in the period 1907 to 1955 compared to 1975 to 2009. Summers were hotter from 1910 to 1955.

From the data plotted above, the sole reason for a warming trend since 1975 is unusually cold winters beginning in 1976 and ending in 1985. Five of the winters in that decade were colder than usual, with no previous decade having more than one equally cold winter.

Cherry-Picking Allegation

The climate alarmists will, as they always do, level a charge of cherry-picking the data by my selection of Abilene for this analysis. It is an empty charge, with no merit, as similar results are found from several other small towns with long temperature records, including Meridian, Mississippi, Dodge City, Kansas, Cape Hatteras, North Carolina, and Fresno, California.

Large City Results

So, then, do the large cities show a similar trend as Abilene? I had a look at three large cities, San Antonio, Texas, El Paso, Texas, and San Diego, California. Both El Paso and San Antonio are relatively near Abilene, both are inland, both have large populations (more than 1 million), with substantial growth in population since 1950. (Abilene is approximately 200 miles from San Antonio, and 400 miles from El Paso). San Diego is a very large city of more than one million population, is at almost the identical latitude as both Abilene and El Paso, has substantial population growth since 1950, but is located on the coast of California.

San Antonio and El Paso show almost identical results, with a small warming trend overall, greater warming trend from 1975 to 2009, but a warming trend of nearly the same degree from 1910 to 1940. The cooling trend from 1940 to 1970 is present, or almost entirely flat for El Paso. The warming from 1975 to 2009 is greater than for Abilene, at 0.049 for San Antonio, and 0.062 for El Paso. Since the CO2 was likely the same for all three cities, yet the large cities had much greater population growth, it is likely that urban heat island heating is the cause of any measured warming in the cities. El Paso shows a warming trend for winters and summers from 1975 to 2009. Yet, the warming trend for El Paso from 1910 to 1940 shows warmer summers but relatively constant nights.

San Diego Cooling

San Diego shows quite a different temperature trend than either El Paso or San Antonio. First, the biggest difference is that San Diego shows cooling from 1975 to 2009, at the rate of -0.0315 degrees C per year, or -3.15 degrees per century. How can this be? Perhaps CO2 is absent from the air over San Diego? No, there are plenty of trees, shrubs, and grass in San Diego and the plants are growing quite well. San Diego also shows a slight warming trend where all the other cities showed cooling or neutral from 1940 to 1970. In San Diego, the trend from 1940 to 1970 was 0.0185 degrees C per year, or 1.85 degrees per century. Yet, the early century period was consistent with all the others, as the warming trend from 1910 to 1940 was 0.0406 degrees C per year, or 4.06 degrees per century.

One might argue that San Diego is cooled by the Pacific Ocean, and thus it could be expected that effect to overwhelm the warming from the CO2. But how then did the city show a warming trend from 1910 to 1940?

Inconsistent CO2

For the climate alarmists to have credibility, they must show that CO2 has an effect in all locations, not just a favored few. CO2 clearly is not consistent, and therefore cannot be the cause of any climate change. Even when one uses their own data, published by their own Hadley Research Center, with all its manipulations and falsifications, clearly the temperature records for the cities in this small study show no abnormal warming in the final quarter of the 20th century, a flat or cooling trend in the middle of the century, and a major city showing a cooling while the others show a warming. CO2 is just a simple, three-atom molecule, one carbon plus two oxygens. It has no capacity for choice or selection or arbitrariness. Yet, the temperature records of San Diego, San Antonio, El Paso, Abilene, and others show that temperature trends are not consistent. Whatever is causing the earth's temperature to increase and decrease over time, and there is no argument that this occurs since ice ages come and go, that something is not CO2.

References:

City/town.............CRU File Number

Abilene, TX ............ 722660

Meridian, MS.......... 722340

Ely, NV.................... 724860

El Paso, TX............. 722700

San Antonio, TX.... 722530

San Diego, CA........ 722900

Cape Hatteras, NC. 723040

Fresno, CA.............. 723890

by Roger E. Sowell, Esq.