For the reasons discussed in a journal article I published last spring, it is clear that the Catastrophic Anthropogenic Global Warming (CAGW) hypothesis does not satisfy the scientific method and thus does not explain global warming/climate change. So what does? The UN Intergovernmental Panel on Climate Change (IPCC) claims that they cannot think of any natural cause, so in their view it must be CAGW, but of course this cannot be correct given the negative findings using the scientific method. But if there is a natural cause, one of the IPCC’s principal but very weak arguments disappears anyway.
This post will sketch one such possible natural hypothesis that has the major advantage that it much better explains the available global temperature data since 1850 on the subject than all of the general circulation models used by the IPCC in their 2007 report.
A Major Natural Cause of Climate Change Needs to Be Much More Carefully Examined
The possible natural cause is that Earth’s climate is primarily but not exclusively determined by variations in the sun, the source of all our heat and light. These variations may in turn be determined by changes in the effects of planetary orbits on the center of mass of the solar system. As the IPCC agrees, there is also an important effect of major volcanic activity, particularly in the mid-latitudes. The IPCC claims, however, that solar variations are too small to explain the observed variations in global termperatures. This appears not to be the case because of indirect effects that the IPCC chose not to examine.
The best known (but not necessarily the only one) of these indirect effects occurs because cosmic rays reaching the Earth’s atmosphere from outer space increase the production of small particles by more than a factor of ten (see Svensmark and Calder and more recently CERN’s Kirkby et al.). This appears to increase the probability of formation of low clouds, which in turn influences the reflection of solar radiation back into space. This, in turn, appears to influence global temperatures since low clouds generally reflect a much higher proportion of solar radiation than the earth or its oceans do. Global climate also appears to be closely related to various oceanic cycles.
There Is an Amazing Relationship between the Various Solar System, Solar, Oceanic, and Climate Cycles
In fact, unlike the poor correlations between CO2 and global temperatures, all these effects–of solar system mechanics on the sun, of solar variations on cloud formation and oceanic cycles, and of cloud formation and oceanic cycles on global temperatures–appear to have amazingly similar cyclical properties. So although the system is quite complex and very little has been done to understand it, this astronomical explanation of climate change appears to be a much more likely hypothesis than the IPCC’s CAGW hypothesis.
Current research suggests that the major solar/global temperature cycles include 20, 60, and approximately 1,000 years, and possibly a 200 or 210 year cycle, in addition to the 100,000 year astronomical/ice age cycle. So if, as it appears, the 60 year cycle reached its peak in the last decade, the 100,000 year cycle about 6,000 years ago, and the 1,000 year cycle either recently, or at the latest, in the next few decades, the prognosis for Earth’s climate under this hypothesis would appear to be for a colder rather than a warmer climate. The only major cycle that may defy this shift, but only for the next ten years, is the 20 year cycle, which appears to be nearing its low point. Various observations of Earth’s climate over the current Holocene period can be explained by assuming reasonable strengths and phases for the solar cycles that have been examined so far. The ice age 100,000 year cycle has long been attributed to astronomical cycles. Why not the shorter cycles as well? Why are they alone unrelated to astronomical cycles as the IPCC argues?
The Need to Move Climate Research Out of Its Current Pre-Copernican, Medieval Mindset on the Earth Alone
Unfortunately, the US has spent well over $100 billion on CAGW research over the past two decades and almost nothing on astronomical hypotheses. I would argue that at least 50 percent of US-funded research should be on non-CAGW hypotheses in order to have a balanced program that gives equal weight to all the possibilities. Surely a major portion of this 50 percent deserves to be used to explore astronomical hypotheses. Some of the obvious tasks are to better determine the major cycles of the solar system, the sun, the oceans, and global temperatures, what phase each one is in, and the extent to which and the mechanisms by which these cycles influence each other.
It is time for climate researchers to go beyond the confines of Earth to seriously examine astronomical sources of climate change. Astronomers have done so for hundreds of years in seeking to understand Earth’s role in the universe; climate researchers need to follow their lead rather than continuing to pretend that the rest of the universe plays only a minor role in climate. It defies common sense to think that the sun that provides all our light and heat has little impact on Earth’s climate. But this is what the IPCC and other CAGW supporters do to this day.
Unfortunately, the underlying reason that little serious research has been done on the astronomical hypotheses for climate change is the same reason that the results of using the scientific method in determining the validity of the CAGW hypothesis have been ignored–little funding is available for non-CAGW research. Research follows the money and for several decades the funding has been primarily for CAGW. Until this changes we are destined to repeat the mistakes, waste, and bad policy prescriptions that have characterized the last two decades in climate research.