We have all heard about the Ice Age, if only in cartoon movies. A time when massive ice sheets covered the planet while mammoths and saber toothed cats roamed the frozen landscape. What is more, the cycle of interglacial-glacial-interglacial has happened over and over again during the past million or so years. During the last half a million years the cycle has repeated every 130,000 years, with the warm period we are now enjoying—the Holocene—just the latest interglacial respite from the icy conditions of the Pleistocene Ice Age. What most people don't know is that there were many areas on Earth that remained unchanged, even during the height of the last glacial period. The Sahara was hot and dry, and in the Amazon rainforests, though a bit smaller in area, looked much like they do today.
A lot has been written about melting ice caps and new mini-ice ages recently. Seems that science can't decide if we are going to drown in rising oceans or starve because summer will be a thing of the past. This leaves the layperson justifiably confused as to who to believe—the climate change alarmists who back rapid global warming or those who warn of a new glacial period. There is little certainty when it comes to science but one thing that can be counted on is our ignorance. Quite simply, scientists cannot predict with any certainty what Earth's climate will do next. If someone tries to tell you different they are lying.
One of the scary scenarios frequently trotted out by climate change alarmists is the possible shutdown of the ocean currents in the Atlantic Ocean. This would disrupt northern hemisphere climate, particularly in Europe. Indeed, one Hollywood disaster movie had frozen military helicopters falling from the skies in the UK and Manhattan buried under a tsunami of ice. We are told this could happen at any time, if the world gets too hot from all that CO2 our species is churning out. Now a shocking new paper in the journal Science implies that the standard view of a relatively stable interglacial circulation may not hold for conditions warmer/fresher than at present. Why? Because it happened before, over 100,000 years ago, without the help of man made global warming. Another catastrophic climate threat is shown to be totally natural and to have happened before our species began burning coal and driving SUVs.
Most people have never heard of the Anthropocene era and with good reason—it is not an officially recognized geologic time period. It is the invention of a small group of scientific busy bodies who evidently have nothing better to do than try to effect a change in the official timeline of Earth's past. The International Commission on Stratigraphy, the body charged with formally designating geological time periods, has been petitioned in the past and just recently a group of chuckle-heads attending the Society for American Archaeology meetings in Hawaii have brought the idea up again. Only problem is, the proponents of the Anthropocene have fallen to arguing amongst themselves—when did the “Age of Man” really start?
Since it was recently Earth Day, a yearly day of celebration and protest by conservationists and assorted greens, it is instructive to take a look at a number of recent studies taken from the scientific literature. The dire predictions made by climate change alarmists are many, far to numerous to all be addressed here, so this article will examine three areas of concern: increased drought, destruction of the world's rainforests, and the die-off of ocean coral reefs. Each of these reported calamities has been linked to increasing anthropogenic greenhouse gas emissions and that supposed bane of nature, anthropogenic global warming (AGW). These threats have been repeated ad nauseum by talking heads and climate change activists, but the truth is that these predicted outcomes are not as threatening as they would have you believe.
It has been vilified in the press and maligned in school classrooms by the ignorant. Opposing it has become a cause célèbre in Hollywood an a litmus test for liberal politicians. Labeled man's chosen weapon for ravaging nature and laying waste to the environment this poor, largely misunderstood gas is in fact essential to our existence. Without carbon dioxide, CO2, we would not be here and Earth would be a frozen lifeless chunk of rock. Forget that life would never have developed on a planet without greenhouse warming, a recent scientific study say the daemon gas has rescued the planet from the deep freeze at least twice during the Neoproterozoic era, roughly 750 to 635 million years ago.
A newly released study from the Research Council of Norway has climate change alarmists abuzz. One of the things the alarmists have been pushing for is to halt warming at a 2°C increase at any cost (and they mean that literally). In the Norwegian study, much to the alarmists' dismay, researchers have arrived at an estimate of 1.9°C as the most likely level of future warming. The report also recognizes that temperatures have stabilized at 2000 levels for the past decade even though CO2 levels have continued to rise. Meanwhile, a reconstruction of the Eemian interglacial from the new NEEM ice core, published in the journal Nature, shows that in spite of a climate 8°C warmer than that of the past millennium, the ice in Northern Greenland was only a few hundred meters lower than its present level. This finding casts doubt on the projected melting of ice sheets and resulting sea-level rise.
A new study in the Proceedings of the National Academy of Sciences (Early Edition on-line), is shaking up science's view of polar bear evolution. Previously, it had been suggested that the white bear of the north was a relatively young species that diverged from brown bears during the last glacial period. That glaciation started after the Eemian epoch (~125,000 years ago), peaking around 25,000 years ago. New genetic analysis pushes that estimated divergence back to 4-5 million years ago, though there seems to have been a significant level of interbreeding between the two species over time. Another important finding is that the polar bear population underwent a significant contraction around 500,000 years ago. According to this new information the polar bear has been around for much longer than previously thought, implying that it has survived many interglacial warm periods. In other words, those who think the polar bear cannot survive the shrinking of Arctic ice packs are dead wrong.
Melting glaciers are once again in the news, along with the associated threat of rising sea levels. NASA satellites have reported wide spread melting across Greenland which has the climate change alarmists all atwitter. But the NASA satellites are providing data never before available, so it is hard to say if the summer melting pattern is unusual. Meanwhile, some 80 year old scientific data has revealed that this is not the first time that there has been a period of glacial retreat in Greenland. This formerly lost data shows that many land-terminating glaciers underwent a more rapid retreat in the 1930s than in the 2000s. Even more interesting is that the two periods of retreat were interrupted by a period of widespread advance from 1943 to 1972. Greenland's glaciers seem to be oscillating with a period of around a century.
The last interglacial period (LIG)—the Eemian—is commonly believed by scientists to have been warmer than the current Holocene interglacial. Along with that balmier climate there is evidence that sea levels were significantly higher than today. Previous studies have pegged Eemian sea levels at 4 to 6m higher than today. Recently, a new investigation raises that estimate, reporting that ancient sea levels peaked between 6.6 and 9.4 m (~20 to 30 feet). Modern day accounts of flooding in low lying coastal areas and tropical islands abound, with ominous suggestions of links to global warming. How high the oceans will rise is a topic of debate for IPCC members, the news media and assorted climate alarmists, but they are asking the wrong question. Instead, they should ask why are sea levels so low?
An iceberg the size of Berlin is forming in Antarctica and is expected to break off from the Pine Island Glacier soon. As sure as night follows day, climate change alarmists will pronounce this a result of anthropogenic global warming—and they will be dead wrong. NASA scientists have already predicted the event and proclaimed it a part of a natural, ten year cycle that they have been studying for decades. The sad state of climate science is underlined by the fact that the researchers felt compelled to state that global warming is not the cause of the ice-shelf collapse.
You know, in science, there was once this thing we called the Theory of Multiple Working Hypotheses. Anathema (a formal ecclesiastical curse accompanied by excommunication) in modern climate science. So, in juxtaposition to the hypothesis of future global climate disruption from CO2, a scientist might well consider an antithesis or two in order to maintain ones objectivity. One such antithesis, which happens to be a long running debate in paleoclimate science, concerns the end Holocene. Or just how long the present interglacial will last.
Since the Mid-Brunhes Event, around 430,000 years ago, interglacial periods have grown warmer and their CO2 levels higher. Research confirms that Croll and Milankovitch were right: Earth's orbital cycles seem to be the cause of these documented cases of true global warming, with CO2 playing a supporting role, not the lead. Many of the catastrophic events warned of by climate change alarmists turn out to be well within the range of natural variation. Moreover, new findings indicate that the effects of the cycle induced changes, through their impact on the environment in the Southern Hemisphere, are not correctly accounted for in the IPCC models.
Earth's climate history includes numerous incidents of rapid warming and cooling. While Pleistocene ice-age glacial terminations are arguably the most dramatic recent examples of sudden climate change, during the last glacial period the climate of the Northern Hemisphere experienced several other significant episodes when the climate rapidly warmed. Scientists call these episodes Dansgaard-Oeschger (DO) events after the Danish and Swiss researchers who documented them using ice-core studies. These rapid oscillations are marked by rapid warming, followed by slower cooling. The most prominent coolings are associated with massive iceberg discharge into the North Atlantic Ocean known as Heinrich events (HE). The melting icebergs add large volumes of cold fresh water to the ocean, disrupting circulation patterns and causing further climate changes. Scientists look to past events like these to help us understand how Earth's climate system functions—what causes our planet to cool or suddenly warm. Recently, new data on past climate changes have led one commentator to predict the end of winter skiing in the American Southwest.
There have been a rash of bogus reports in the news media about rapidly rising sea-levels supposedly caused by global warming. Sea-levels are notoriously hard to measure on a global basis since land also rises and sinks due to tectonic activity. With historical records mostly unreliable how can we tell if current conditions are normal for Earth 14,000 years after a deglaciation? A new report, based on calcium growths in caves on the Mediterranean island of Mallorca, says that sea levels around 81,000 years ago were higher than today. Higher sea-levels imply less glacial ice and warmer temperatures than today as well. Even more interesting is that this occurred during a warm period called marine isotope stage (MIS) 5a, which was more than 30,000 years after the Eemian interglacial ended and glaciation had resumed. This could mean that current theories about how ice age glacial periods start are wrong.