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2011 Climate Change Index

The IGBP Climate-Change Index provides a snapshot of global climate change. It highlights the general trend by bringing together key climate-change indicators: atmospheric carbon dioxide, temperature, sea level and sea ice.
The Climate Change Index works like the Dow Jones Index, but instead of providing a snapshot of financial markets, it gives an annual snapshot of how the planet's complex systems - the ice, the oceans, the land surface and the atmosphere - are changing.

How is the index calculated?
The reference point is 1980 - the earliest date the index has been calculated. The annual change of each parameter (carbon dioxide, sea level, temperature, Arctic sea-ice minimum) is normalised (between 1980 and 2007).  Zero is no annual change. One hundred is the maximum-recorded annual change between 1980 and 2007. Minus one hundred is the minimum change between 1980 and 2007.

Each year, we take the average of the normalised parameters. This gives the index for the year. The value of the index for each year is added to that of the previous year to show the cumulative effect of annual change.

The Climate Change Index is in development and subject to review.

Climate Change Index - Bar chart, cumulative. Credit: International Geosphere-Biosphere Programme
Climate Change Index - Cumulative. Credit: International Geosphere-Biosphere Programme
Data source:
ftp://ftp.cmdl.noaa.gov/ccg/co2/trends/co2_annmean_mlo.txt
Reference: Dr. Pieter Tans, NOAA/ESRL (www.esrl.noaa.gov/gmd/ccgg/trends/) and Dr. Ralph Keeling, Scripps Institution of Oceanography (scrippsco2.ucsd.edu/)
Data source:
ftp://sidads.colorado.edu/DATASETS/NOAA/G02135/Sep/N_09_area.txt

Climate-change index from 1980, including cumulative change

  Global land surface temp. anomaly Atmos. CO2 N. hemis. minimum sea ice extent Sea level Climate Index Climate Index Cumulative
             
Year Degrees C ppm mill km2 mm
1980 14.30 338.68 7.85 142.20 28 28
1981 14.39 340.10 7.25 154.60 49 77
1982 14.09 341.44 7.45 148.90 -21 56
1983 14.34 343.03 7.52 157.30 44 100
1984 14.16 344.58 7.17 156.30 4 104
1985 14.14 346.04 6.93 146.00 -6 98
1986 14.20 347.39 7.54 146.70 9 107
1987 14.35 349.16 7.48 147.30 26 133
1988 14.43 351.56 7.49 152.00 34 167
1989 14.31 353.07 7.04 156.40 19 186
1990 14.46 354.35 6.24 157.80 33 219
1991 14.45 355.57 6.55 160.90 12 230
1992 14.17 356.38 7.55 163.70 -18 212
1993 14.2 357.07 6.50 159.33 12 225
1994 14.32 358.82 7.18 163.18 21 246
1995 14.51 360.80 6.13 168.76 52 298
1996 14.43 362.59 7.88 169.86 -10 288
1997 14.47 363.71 6.74 175.45 37 325
1998 14.77 366.65 6.56 177.75 50 375
1999 14.51 368.33 6.24 178.38 3 378
2000 14.50 369.52 6.32 180.73 13 391
2001 14.60 371.13 6.75 186.91 26 417
2002 14.71 373.22 5.96 190.83 42 459
2003 14.70 375.77 6.15 193.39 23 482
2004 14.63 377.49 6.05 196.85 18 500
2005 14.80 379.80 5.57 201.61 45 545
2006 14.70 381.90 5.92 203.34 10 555
2007 14.78 383.77 4.30 203.71 42 596
2008 14.57 385.59 4.73 208.37 6 602
2009 14.72 387.38 5.39 212.42 24 626
2010 14.86 389.78 4.93 213.75 37 663
2011 14.72 391.57 4.61 215.00 10 672

Data

Global Temperature Anomaly

Data - NASA Goddard Institute for Space Studies
http://data.giss.nasa.gov/gistemp/tabledata/GLB.Ts.txt
(Downloaded 25 January 2012)

Carbon dioxide

Data Carbon Dioxide Information Analysis Center (CDIAC)
ftp://ftp.cmdl.noaa.gov/ccg/co2/trends/co2_annmean_mlo.txt
Ref: Dr. Pieter Tans, NOAA/ESRL (www.esrl.noaa.gov/gmd/ccgg/trends/) and Dr. Ralph Keeling, Scripps Institution of Oceanography (scrippsco2.ucsd.edu/)
(Downloaded 25 January 2012)

Sea level

Data - Church and White Global Mean Sea Level Reconstruction
Proudman Oceanographic Laboratory
http://www.cmar.csiro.au/sealevel/sl_data_cmar.html
(Downloaded 23 February 2012)

Sea ice (Arctic minimum)

Data -  National Snow and Ice Center (Boulder Colorado)
ftp://sidads.colorado.edu/DATASETS/NOAA/G02135/Sep/N_09_area.txt
(Downloaded 25 January 2012)

Two-minute film about the index

Watch a short film that explains the index.