Average GLOBAL temperature anomalies* are reported on the web by NOAA (National Oceanic and Atmospheric Administration)
HADcrut3 (Met office Hadley Centre, UK)
GISS (Goddard Institute of Space Studies)
UAH (University of Alabama at Huntsville)
RSS (Remote Sensing Systems)
The first three all draw from the same data base of surface measurement data. The last two draw from the data base of satellite measurements. Each agency processes the data slightly differently from the others. Each believes that their way is most accurate. To avoid bias, I average all five.
The averages since 2001 are listed here.
*A temperature anomaly is simply the difference between a measured temperature and a reference temperature, such as the average for some previous time period.
A straight line fit to these data has zero slope (actually slightly negative). That means that, for over a decade, average global temperature has not changed.
These data, but with noted offsets applied to approximately compensate for differences in reference temperatures, are graphed (through the month noted) in Figure 1, below.
Rising Atmospheric CO2 Level and Not-Rising Temperature
To test if atmospheric carbon dioxide is a direct driver for a change of temperature may be examined by differencing the month-to-month changes in both. Graphically, this is constructed by, each month, subtracting the percent change of the temperature anomaly since 2001 from the percent change of atmospheric carbon dioxide since 2001. Any sustained ‘separation’ vs. time would indicate other important drivers to temperature change.
The resulting graph is displayed as Figure 2. It corroborates the weak connection between the atmospheric carbon dioxide level and average global temperature.
The NOAA temperature anomaly data used in this comparison are from ftp://ftp.ncdc.noaa.gov/pub/data/anomalies/monthly.land_ocean.90S.90N.df_1901-2000mean.dat . The percent change of temperature anomaly is calculated by subtracting the current value from the average value for 2001 and dividing the difference by 0.74°C which is the usually accepted value for average global temperature increase during the 20th century.
Similarly, the percent change in CO2 level is obtained by subtracting the Mauna Loa season-corrected value for June, 2001 as given at ftp://ftp.cmdl.noaa.gov/ccg/co2/trends/co2_mm_mlo.txt from the current season-corrected value and dividing this difference by 89.5 ppmv which is the increase from 1800 (281.6) to 2001 (371.1).
The Mauna Loa data are representative of the entire planet as demonstrated by a co-plot of the atmospheric CO2 level at several places and times in a graph on page 7 of Reference 1.
The average level of atmospheric CO2 in 2012 was 393.82 ppmv (ftp://ftp.cmdl.noaa.gov/ccg/co2/trends/co2_annmean_mlo.txt ) which is 22.7 ppmv more than in 2001. It is not credible that an increase of 89.5 ppmv caused the temperature rise called Global Warming but that a further increase of 22.7 ppmv caused no increase in average global temperature.
This data corroborates the finding disclosed at http://www.middlebury.net/op-ed/pangburn.html that “carbon dioxide change does NOT cause significant climate change”.
Variation of Temperature Measurements
The substantial scatter, in the Figure 2 data, primarily results from artifacts of the temperature measurement process as discussed starting on page 4 of Reference 1.
A major contributor to this scatter is demonstrated in animations of sea surface temperatures shown at
Recent global temperature anomalies reported monthly by the five agencies are graphed in Figure 3. This graph shows the erratic behavior of the reported values. However, the huge effective thermal capacitance of the oceans (about 30 times everything else) absolutely prohibits such rapid changes in actual average global temperature. Thus the measurements contain a substantial random component that is an artifact of the measurement process.
An explanation of the causes of the variation in reported surface temperature data obtained via meteorological satellites is at http://www.drroyspencer.com/2012/03/what-causes-the-large-swings-in-global-satellite-temperatures/
The ’29&71’ anomalies shown in Figure 1 are simply 29% of the land temperature anomaly reported by NOAA added to 71% of the ocean temperature anomaly reported by NOAA at the stated website. The percent values are simply the fraction of the surface area of the planet covered by each.
NOAA also reports a single four-digit number for the average global temperature anomaly each month at ftp://ftp.ncdc.noaa.gov/pub/data/anomalies/monthly.land_ocean.90S.90N.df_1901-2000mean.dat . The plot identified as ‘NOAA ref’ in Figure 3 displays these values.
Reporting a value with four significant figures for anomalies is mathematically possible because many separate measurements are averaged. It is a misleading indication of accuracy, however, because the reported values have an apparently random variability with a standard deviation of approximately ± 0.1°C with respect to the trend. This magnitude of variability in actual average global temperature is prohibited by the physics. The uncertainty of the trend average for the 12 years is about 1/√12 times the standard deviation of the individual measurements or only about ± 0.03°C.
Long Term Assessment
An assessment including earlier data is presented in a paper titled ‘Natural Climate change has been hiding in plain sight’ which is at http://climatechange90.blogspot.com/2013/05/natural-climate-change-has-been.html . This paper presents a simple equation that calculates average global temperatures since they have been accurately measured world wide with an accuracy of 90%, irrespective of whether the influence of CO2 is included or not. The equation uses a proxy of the time-integral of sunspot numbers. A graph is included which shows the calculated trajectory overlaid on measurements.
Future Average Global Temperature
Future temperature anomalies depend on future sunspot numbers and future ocean temperature oscillation behavior, neither of which has been confidently predicted for more than a decade or so in advance. The effective sea surface temperature oscillation has been consistent for over a century. It has been dominated by the PDO, which has been observed to fade for periods over the years (MacDonald and Case, 2005).
The effective global sea surface temperature oscillation, although dominated by the PDO, depends also on complex phase interaction with lesser oscillations. Considering all this, the effective sea surface oscillation can be expected to fade in and out in its contribution to AGT in future decades. However, average global temperature should continue to correlate with the time-integral of sunspot numbers, as it has ever since sunspots have been regularly recorded.
Humanity has wasted over $100,000,000,000 in failed attempts using super computers to demonstrate that added atmospheric CO2 is a primary cause of global warming and in misguided activities to try to do something about it. An unfunded engineer, using only a desk top computer, applying a little science and some engineering, discovered a simple equation that unveils the mystery of global warming and describes what actually drives average global temperature. The many documents produced along the way to this discovery are at http://climaterealists.com/index.php?tid=145&linkbox=true . The refined version of the equation is presented at http://climatechange90.blogspot.com/2013/05/natural-climate-change-has-been.html .
Source: End of GW