by Wm. Robert Johnston
last updated 7 September 2005
For details and sources on data series, see Historical data relating to global climate change.
Graph shows average annual atmospheric concentrations of carbon dioxide, in parts per million by volume.
Graph shows annual increase in atmospheric inventory of carbon dioxide and annual release of carbon dioxide from man-made sources (including fossil fuel consumption, gas flaring, and cement production). Both series are given in teragrams of carbon.
Graph shows two separate series pertaining to the atmosphere's absorption or reflection of sunlight. The volcanic dust index is model-based values of the amount of sunlight either reflected or absorbed by volcanic dust, expressed as a global annual average. Values towards the bottom of the graph correspond to more sunlight absorbed/reflected, i.e. to a potential cooling effect. The albedo index is the relative change in the Earth's albedo (fraction of visible light reflected back to space), as an annual average, and is mostly determined by cloud cover. Values towards the top of the graph correspond to more sunlight absorbed by the Earth, i.e. to a potential warming effect.
Graph shows average annual solar irradiance in two series: one from direct measurements (by satellites) and one reconstructed from historical proxy indicators. Both are in watts per square meter.
Graph shows five time series of mean global temperature variations, relative to the average from 1979 to 1988 (with the exception of the radiosonode-Sterin series). The two surface series and the radiosonode (Angell) series are for surface temperature; the satellite-based measurement series and the radiosonode (Sterin) series are for the lower atmosphere.
© 2002-2003, 2005 by Wm. Robert Johnston.
Last modified 7 September 2005.
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