Index of /MATLAB/SeeForcing

[ICO]NameLast modifiedSizeDescription

[DIR]Parent Directory  -  
[TXT]CO2.csv14-Nov-2015 12:21 1.0K 
[TXT]HadCRUT4.csv14-Nov-2015 12:22 1.1K 
[TXT]TSI.csv14-Nov-2015 12:23 1.6K 
[   ]ma.m05-May-2013 15:01 85  
[   ]sf.m17-Nov-2015 00:18 4.3K 

This directory contains MATLAB scripts and .csv data for visualizing the correlation of HadCRUT4 with CO2 forcing defined as log2(CO2/280).

Key files are as follows.

sf.m: The MATLAB script that does the work. Further instructions at top of file.

Data files: CO2.csv, HadCRUT4.csv, TSI.csv. Each has 147 lines of data, one datum per line, for the years 1868-2014 inclusive.

CO2.csv: Mandatory file with 2 columns. Any source of CO2 data is fine. The one provided here is Law Dome for 1868 to 1960 and the Mauna Loa Keeling curve thereafter.

The main output is this figure (right click and select "Open Link in New Window") showing the five curves named in the legend. The important points to note are:

  • HadCRUT4, 11-yr smoothing (grey curve). This is enough smoothing to remove solar cycles and 3-7 year ENSO events.
  • HadCRUT4, 65-yr smoothing (blue curve). This is enough to remove the 65-year Atlantic Multidecadal oscillation and everything faster.
  • The 65-year filter is not sufficient to remove the gradual rise in Total Solar Irradiance (TSI) during 1900-1950. The orange line shows Solar Forcing, 21-year.
  • Subtracting Solar Forcing (the orange line) from HadCRUT65 (the blue line) yields the much straighter red line, which rises in direct proportion to CO2 forcing.
  • The green line is the trend line fitted to the red curve with an R2 of 0.9990 (1-R2 = 0.10%). The blue line (HadCRUT4, 65-yr) is not as straight, with an R2 of only 0.99 (1-R2 = 1.03%).
  • The slope of the green line indicates CO2 has a climate sensitivity of has a 1.73 °C/doubling of CO2.
  • During the 31 years 1910-1940:
  • The grey 11-year HadCRUT4 rises about 0.4 °C.
  • The blue 65-yr HadCRUT4 curve rises about 0.13 °C.
  • The orange solar forcing curve rises about 0.055 °C.
  • Subtracting solar forcing (orange) from HadCRUT4 (blue) yields the very straight red curve. Its trend line (green) indicates a rise in GHG warming of 0.137 °C.
  • It follows that the 0.4 °C rise in 11-year HadCRUT4 can be split 2:1, with the 2 parts associated with whatever the 65-year filter removed and the 1 part with GHG forcing (0.082 °C) and solar forcing (0.055 °C)