Breaking News: The Climate Actually Changes! - Larry Bell - The Bell Tells for You - Forbes

Breaking News: The Climate Actually Changes!
May. 3 2011 - 12:03 pm
By LARRY BELL

The new convention is to refer to “global warming” (something many have told us to worry about) as “climate change” (meaning pretty much the same thing since it’s supposed to be bad and caused by us anyway). The main difference appears to be that climate change is even worse, since global warming also causes global cooling along with a seemingly endless variety of other carbon dioxide-induced upheavals that we are responsible for.

So whenever someone asks whether I believe in global warming, (aka climate change) the simple answer is YES. In fact, I don’t really know anyone who doesn’t. If so they clearly aren’t very old or observant! On the other hand, I don’t buy into the causes, consequences or remedies that alarmists project.

Cyclical, abrupt and dramatic global and regional temperature fluctuations have occurred over millions of years, long before humans invented agriculture, industries, internal combustion engines or carbon-trading schemes. Many natural factors are known to contribute to these changes, although even the most sophisticated climate models and theories cannot even begin to predict the timing, scale (either up or down) or future impacts — much less the marginal contributions of various human influences.

And while global warming has been trumpeted as an epic climate change crisis with human-produced CO2, a trace atmospheric “greenhouse gas” branded as a primary culprit and endangering “pollutant”, don’t be too sure about the veracity of those pitches. Throughout earlier periods of Earth’s history those levels have been many times higher than today, with temperature changes preceding — not following — atmospheric CO2 changes. It doesn’t require a degree in a climate science, or rocket science either for that matter, to understand these basic facts.

Fossil records reveal that atmospheric CO2 levels around 600 million years ago were about 7,000 parts per million, compared with 379 ppm in 2005. Then approximately 480 million years ago those levels gradually dropped to 4,000 ppm over about 100 million years, while average temperatures remained at a steady 72 degrees. They then jumped rapidly to 4,500 ppm and guess what! Temperatures dove to an estimated average similar to today, even though the CO2 level was around twelve times higher than now. Yes, as CO2 went up, temperatures plummeted.

About 438 million years ago, atmospheric CO2 dropped from 4,500 ppm to 3,000 ppm, yet according to fossil records, world temperatures shot rapidly back up to an average 72 degrees. So regardless of whether CO2 levels were 7,000 ppm or 3,000 ppm, temperatures rose and fell independently.

Over those past 600 million years there have been only three periods, including now, when Earth’s average temperature has been as low as 54 degrees. One occurred about 315 million years ago, during a 45-million-year-long cool spell called the Late Carboniferous period, which established the beginning of most of our planet’s (gasp) coalfields. Both CO2 and temperatures shot back up at the end of it just when the main Mesozoic dinosaur era was commencing. CO2 levels rose to between 1,200 ppm and 1,800 ppm, and temperatures again returned to the average 72 degrees that Earth seemed to prefer.

Around 180 million years ago, CO2 rocketed up from about 1,200 ppm to 2,500 ppm. And would you believe it? This coincided again with another big temperature dive from 72 degrees to about 61 degrees. Then at the border between the Jurassic period when T. Rex ruled and the Cretaceous period that followed, CO2 levels dropped again, while temperatures soared back to 72 degrees and remained at that level (about 20 degrees higher than now) until long after prodigious populations of dinosaurs became extinct. And flatulent as those creatures may possibly have been, at least there is no evidence that they burned coal or drove SUVs.

Based upon a variety of proxy indicators, such as ice core and ocean sediment samples, our planet has endured large climate swings on a number of occasions over the past 1.5 million years due to a number of natural causes. Included are seasonal warming and cooling effects of plant growth cycles, greenhouse gases and aerosols emitted from volcanic eruptions, Earth orbit and solar changes, and other contributors with combined influences. Yet atmospheric CO2 levels have remained relatively low over the past 650,000 years, even during the six previous interglacial periods when global temperatures were as much as 9 degrees warmer than temperatures we currently enjoy.

Over the past 400,000 years, much of the Northern Hemisphere has been covered by ice up to miles thick at regular intervals lasting about 100,000 years each. Much shorter interglacial cycles like our current one lasting 12,000 to 18,000 years have offered reprieves from bitter cold. Yes, from this perspective current temperatures are abnormally warm. By about 12,000 to 15,000 years ago Earth had warmed enough to halt the advance of glaciers and cause sea levels to rise, and the average temperature has gradually increased on a fairly constant basis ever since, with brief intermissions.

During a period from about 750 BC to 200 BC, before the founding of Rome, temperatures dropped and European glaciers advanced. Then the climate warmed again, and by 150 BC grapes and olives were first recorded to be cultivated in northern Italy. As recently as 1,000 years ago (during the “Medieval Warm Period”), Icelandic Vikings were raising cattle, sheep and goats in grasslands on Greenland’s southwestern coast. Then, around 1200, temperatures began to drop, and Norse settlements were abandoned by about 1350. Atlantic pack ice began to grow around 1250, and shortened growing seasons and unreliable weather patterns, including torrential rains in Northern Europe led to the “Great Famine” of 1315-1317.

Temperatures dropped dramatically in the middle of the 16th century, and although there were notable year year-to-year fluctuations, the coldest regime since the last Ice Age (a period termed the “Little Ice Age”) dominated the next hundred and fifty years or more. Food shortages killed millions in Europe between 1690 and 1700, followed by more famines in 1725 and 1816. The end of this time witnessed brutal winter temperatures suffered by Washington’s troops at Valley Forge in 1777, and Napoleon’s bitterly cold retreat from Russia in 1812.

Although temperatures have been generally mild over the past 500 years, we should remember that significant fluctuations are normal. The past century has witnessed two distinct periods of warming. The first occurred between 1900 and 1945, and the second, following a slight cool-down began quite abruptly in 1975. That second period rose at quite a constant rate until 1998, and then stopped and began falling again after reaching a high of 1.16 degrees above the average global mean.

About half of all estimated warming since 1900 occurred before the mid-1940s despite continuously rising CO2 levels. Even U.K. East Anglia University Climate Research Unit (CRU) Director Phil Jones has admitted that there has been no statistically significant warming for at least a decade. He has also admitted that temperatures during the Middle Ages may have been higher than today.

So perhaps you’ll wish to ponder this question; Given that over most of the Earth’s known climate history, the atmospheric CO2 levels have been between four and eighteen times higher than now – throughout many times when life not only survived but also flourished; times that preceded humans; times when CO2 levels and temperatures moved in different directions – how much difference will putting caps on emissions accomplish? Consider also that about 97% of all current atmospheric CO2 derives from natural sources.

And yes, change is the true nature of climate. After all, if climate didn’t change, we really wouldn’t need a word for it would we? Wouldn’t it all just be “weather”?