Today we are constantly deluged with material on climate change, some more alarming than others. Of course, there is no question that global warming has happened, but on this matter we with our usual human arrogance blame ourselves. True, we have aggravated the situation and true, we can lessen the problem, but the ultimate cause has little to do with mankind (and little to do with carbon dioxide, for that matter), just as the Little Ice Age that went from the 13th to the 18/19th century had little to do with human causes.
In the time before the Little Ice Age, the world was considerably warmer than it is now, even though the so-called greenhouse gases were very low. Here are two bits of evidence – in brief.
In England, grapes were grown throughout the country. In fact, so much wine was being made that the French complained about the influx of English wines. When the ice age began to take hold, the grape crops started to fail. People had to stop drinking wine, and turn to beer because barley (especially) and other grains did OK. As we got to the coldest time of the Little Ice Age, the years leading up to the French Revolution, even the grain crops started to fail. The French were particularly affected, because the peasants had refused to make the switch to potatoes, which were less affected. These famines contributed significantly to the revolution.
Another piece of evidence is Greenland. I have seen it suggested that Eric the Red called it “green land†to attract settlers, but this is not true. Greenland was in fact green, with luscious pastures for grazing, etc. The Greenland colony traded with Norway via ships that arrived at least once a month. After some 200 years of the colony’s existence, the climate began to change. The Little Ice Age had arrived. Snow and ice advanced, while the green fields retreated. Summers became very short. Ships could only rarely arrive through the ice bound seas. Finally, they couldn’t get through any more. The colony hung on as well as it could, but by the fifteenth century it had disappeared.
The real causes of global warming (and cooling) are of cosmic origin, as detailed in The Chilling Stars by Henrik Svensmark and increasingly verified by his subsequent work. The book is highly recommended reading.
I think the reason why Svensmark’s work is not at the forefront of discussion is threefold: (1) Svensmark is Danish, not American; (2) in the early years of awareness of climate change, any voices that appeared to be against mankind’s contribution to global warming were downplayed or attacked (Svensmark, however, supports the human contribution); and (3) the idea that humans are the cause of global warming is now so orthodox, so established, and everyone is jumping on the band wagon, that more rational investigatory voices are not being heard.
If the cause of global warming is not human, should we just go ahead on our own merry way? I think not. Apart from making sure that we adapt to climate change, the steps we are taking (or are being encouraged to take) will still be beneficial to the environment. Cutting down carbon dioxide emissions from vehicles or coal-driven power plants also cuts down other pollutants. Driving cars with better mileage, conservation and recycling—all these environmentally beneficial habits help to conserve our natural resources.
Does Svensmark’s theory give an explanation of the “hockey stick” graph? Does he have a theory on the natural cause of that rapid rise in global temperature? Also, it sounds like you’re worried more less about CO2 than other pollutants, so perhaps you think burning natural gas is a good idea? It has very little combustion byproducts other than carbon dioxide and water.
I’m not particularly concerned about CO2 as a greenhouse gas. Incidentally, other gases, such as methane and water vapor, are more potent in this respect. However, there may be unforeseeable consequences in having excessive CO2 in the atmosphere. For instance, one “positive†consequence would be increased plant growth, due to more available CO2.
The “hockey stick†graph is based on controversial estimations, flawed calculations and serious data defects. There doesn’t seem to be much value in addressing it until the controversies are resolved. Nevertheless, since we have just recently emerged from the Little Ice Age, a temperature graph over the last 500 years will approximate to something like a hockey stick.
Svensmark’s theory of climate change is based on the interplay of clouds, the sun and cosmic rays. His research has shown that cosmic rays play a major role in the formation of clouds, particularly the lower level clouds that have the highest reflective value. The more vigorous the action of the sun is, the fewer the cosmic rays that enter our atmosphere. During the Little Ice Age, for instance, solar activity was at a low. Before then was the Medieval Warm Period, and there have been similar fluctuations over the last 12,000 years. The Modern Warm Period (what we call Global Warming) is an interval in time when the sun has become more active and cosmic rays have become relatively scarce. (The historical data are based on ice core deposits of radioactive beryllium-10, which are made in the atmosphere by cosmic rays, and so are factually accurate as opposed to estimations of the “hockey stick†proponents.)
Oh, yes, I think natural gas is a great fuel. Its main shortcoming is that it cannot be replaced.