Wednesday, 13 May 2009

Dirk Callebaut is not a climate skeptic

Even though it's rather old news from 2006 or so, i still see people expressing the belief that Belgian physicist Dirk Callebaut would be a climate skeptic.

It's a misbelief originating by something written by Hans Labohm.
Recently the astronomer Khabibullo Abdusamatov of the Pulkovo Astronomic Observatory in St. Petersburg declared that the Earth will experience a "mini Ice Age" in the middle of this century, caused by low solar activity. Temperatures will begin falling six or seven years from now, when global warming caused by increased solar activity in the 20th century reaches its peak. The coldest period will occur 15 to 20 years after a major solar output decline between 2035 and 2045, Abdusamatov said.

This view is shared by the Belgian astronomer, Dirk Callebaut, who expects a "grand minimum" in the middle of this century, just like the Maunder Minimum (1650-1700), a period during which the Thames, the Seine and the Dutch canals were frozen in winter.

It is clear that nowhere is written that Callebaut is a climate skeptic, neverthless by the way the paragraph is written many people interprete it this way.

It is true that Callebaut thinks there'll be a cooling effect of a solar "Grand Minimum". But this doesn't make him something even remotely close to a climate skeptic.

Read what Callebaut says himself :

Climate: Warning!

It is still unclear how much of the global warming can be ascribed to the high activity of the Sun during the twentieth century and how much is due to the human activity (green house effect). Callebaut, Makarov and Tlatov (2002a,b) and Makarov et al. (2002) estimated the increase in temperature on the Earth since the Maunder Minimum to be about 1±C. This value is in the range of other estimates (Cliver et al.,1998), based on a different approach. Moreover, it is well known that the period of the Maunder Minimum corresponds to a small 'ice age'.

However, the fairly large value of the temperature change has no clear explanation: the extra energy (about 0.1% of the total irradiation) during a maximum of a cycle can yield about 0.1±C only. The extra energy which can be caught thanks to the magnetic field from the solar wind can account for a similar value. Cliver et al. (1998) suggest that a longterm component of the solar forcing is present. Alternatively the indirect effect of the magnetic field on the cosmic rays and thus on the (low) clouds has been invoked to explain the great effect of a deep minimum on the temperature on Earth (Svensmark, 2007).

Whether we have a good explanation for it or not the gradual decrease to be expected in the coming deep minimum is thus 1±C. However, this will cause only a small slowing down of the global warming up due to human activity.

By no means it should incite to an euphoric use of oil or gas; on the contrary: after the deep minimum is over (taking about 50 years) the lost 1±C will be recovered leading to a catastrophe if the pollution due to carbon dioxide etc. has not been reduced seriously from its present day level. The need for alternative energy sources (solar and wind energy and most of all fusion) remains imperative.


Compare what Callebaut wrote to these words from Hans Labohm:
Currently, there is a growing number astrophysicists, who foresee a new little ice age in the near future, which is often referred to as a new Dalton minimum. They include scientists, such as Khabibullo Abdusamatov, Dirk Callebaut, David Hathaway and Olech Sorochtin.

The latter is member of the Russian Academy of Physical Science. In October 2007 his views were prominently disseminated by the Russian press agency Novosti, which in the period of the Cold War was generally considered to be a mouthpiece of the Kremlin.

Therefore, it is perhaps not too far-fetched to speculate that this might be a warning signal that the Rus­sians will drop out of Kyoto, when its first phase ex­pires in 2012.

If – a big if – these astrophysicists are right, the global warming hype will soon be over, while the Kyoto Protocol will prove to be redundant.

It's a nice example of how readers have to be careful not to be mislead by a suggestive way a text can be written in.

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