Science Heresy

November 2012


Fig 2 (lower) of Humlum et al 2012 showing that atmospheric CO2 concentrations lag behind global temperature variations by about a year.

Climate Change is not Man-Made

  In August this year a key paper became available on the Web. The paper, by Humlum, Stordahl and Solheim, has been accepted for publication by the peer-reviewed journal Global and Planetary Change and will be published in hard copy form before the end of the year.

They show that atmospheric CO2 consistently LAGS ocean temperature.

Their data sources are impeccable and in the public domain. What they did was carry out the sort of statistical analysis which should have been done by the IPCC 30 years ago.

This is a very important paper because it constitutes the first direct experimental refutation of the theory that increased atmospheric CO2 from industrial activity is the cause of increased global average temperatures. The lag between them indicates this cannot be the case; an effect cannot precede its cause.


  • The overall global temperature change sequence of events appears to be from 1) the ocean surface to 2) the land surface to 3) the lower troposphere.

  • Changes in global atmospheric CO2 are lagging about 11-12 months behind changes in global sea surface temperature.
  • Changes in global atmospheric CO2 are lagging 9.5-10 months behind changes in global air surface temperature.

  • Changes in global atmospheric CO2 are lagging about 9 months behind changes in global lower troposphere temperature.
  • Changes in ocean temperatures appear to explain a substantial part of the observed changes in atmospheric CO2 since January 1980.

  • CO2 released from use of fossil fuels has little influence on the observed changes in the amount of atmospheric CO2, and changes in atmospheric CO2 are not tracking changes in human emissions.
  What are the implications?

The time scale here ranges from months to decades. It has been known for some time that ice-cores reveal a similar effect on a time scale of centuries to millennia where a lag of several centuries has been observed. This paper is important because the theory of human-induced climate change (formerly known as the Anthropogenic Global Warming or AGW theory) proposes that certain gasses CO2, O3 and H2O trap infrared back-radiation from the earth as it radiates into space and that increases in concentrations of these greenhouse gasses will inevitably lead to greater warming of the lower atmosphere. The observations presented by Humlum et al clearly show that such warming commences in the sea, not in the lower atmosphere as required by the AGW theory. The AGW theory cannot account for the observations of Humlum et al and must be abandoned.

The AGW theory has been looking rather flaky for some time. It is well known that the temperature of lower atmosphere is controlled by convection and hence by the thermodynamic properties of gasses, not by radiation which only becomes important at the "top of the atmosphere" (i.e. above the tropopause) where water vapour concentrations become very small. The lower atmosphere is already opaque to infrared and adding further CO2 makes little difference. This theory is confirmed by observation thousands of times a day when met balloons measure the "adiabatic lapse rate", the rate at which temperature falls off with height. Furthermore the numerical "climate models" (OAGCMs) have never been able to predict the observed geographical distribution of temperature variations accurately (see here) and they have also failed to predict the plateau in global temperature of the last decade which has occurred despite continued increases in atmospheric CO2 concentration.

This paper is, or should be, the final nail in the coffin of the absurdly simplistic AGW theory.


  What alternatives are there?

A close association between CO2 concentration in the atmosphere and global temperature has long been apparent. It is observed in ice-core records going back nearly a million years as well as on shorter timescales as discussed here. There are two possible mechanisms. Either it exists because (a) atmospheric CO2 traps infrared radiation or (b) the warming of seawater causes it to release more CO2 into the atmosphere.

Explanation (a) was first proposed by the Swedish chemist Arrhenius who was aware that CO2 was a strong absorber of infrared radiation. Unfortunately, at this early stage, Arrhenius did not know about convective cooling and the "adiabatic lapse rate". These are not mentioned in his 1896 paper.

Explanation (b) fits the one year lag of the Humlum et al observations and also explains the multi-century lag which occurs when the earth was warmed during ice-age terminations. The different time lags are explicable in terms of the different water masses being warmed or cooled. Short term variations only affect the mixed layer, the upper 100m or so of the ocean, whereas long term changes affect the deep ocean. The circulation of deep ocean currents takes centuries. When an opened can of soft drink warms up when it is removed from the refrigerator it loses its CO2 bubbles at a faster rate. When the earth comes out of an ice age and the deep ocean warms up, it also loses its dissolved CO2 at a faster rate.

The alarmist view that observations of the steadily increasing atmospheric CO2 concentrations of the 20th century are due entirely to industrialization is not supported by the analysis of Humlum et al. Instead it seems more likely that it is due to the upwelling of deep ocean water masses. This may be questioned by oceanographers since there is no smoking gun. However degassing of CO2 by upwelling water is impossible  to measure because of the abundance of respiring plankton in such places. Oceanographers naively assume that the oceans are always in steady state and completely ignore major forcing due to hydrothermal vents and submarine volcanoes.

This idea that variations in climate can be explained in terms of ocean instabilities is not new. The effects of the ocean instability in the Equatorial Pacific, El Nio, have been known for some time. The idea that other random or quasi-periodic variations in ocean circulation exist and have similar climatic consequences is a reasonable assumption.



Humlum, Ole, Stordahl, Kjell, Solheim, Jan-Erik, The phase relation between atmospheric carbon dioxide and global temperature, Global and Planetary Change (2012), doi: 10.1016/j.gloplacha.2012.08.008



November 2012