The current interglacial warm period, the Holocene, started ∼11,500 years ago. At its start, among the dramatic changes in climate was a notable increase in rainfall, triggered by summer insolation values higher than those of today. This caused what is called the African Humid Period in North Africa—a time when the Sahara was dotted with large and small lakes, savannah grasslands, and in some regions, humid tropical forests and shrubs. The African Humid Period ended abruptly ∼5000 ybp (years before present) in many locations, such as western North Africa and northern Kenya. In other places, such as the central Sahara and the southern Arabian Peninsula, change occurred more gradually, taking several millennia. Regardless of the pace of change, those areas are tracts of arid desert today, and the animals and humans who had previously thrived in those formerly verdant regions have either moved or had to adapt to much harsher conditions. This is but one example of nature at its most capricious—the tyranny of climate change.
Unless you have been living in one of the few truly remote areas of the planet, you have been exposed to them. Climate change memes that pass from person to person and are repeated without thought or critical examination. They range from the subtle—bad weather is being increased by global warming—to the banal—over 97% of scientists agree about climate change. We are bombarded with these unsubstantiated ideas over and over again, from talking heads on TV, newspaper headlines, our friends and even the president of the United States. They are blatant untruths that have become legitimized by repetition, until school children and adults alike patriot them to each other. The recent tropical cyclone, Haiyan, has triggered another round of meme infection: it was the worst storm in history, tropical storms are getting bigger every year, there are more storms every year, and, of course, they are all caused by global warming. Trouble is, these “facts” are all false.
Much has been done to vilify carbon dioxide in the media. Listening to the talking heads and on-air “experts” could lead one to believe that CO2 is an evil scourge that the world would be better off without. Nothing could be further than the truth. CO2 is necessary for life on Earth, forests in particular. It is not just plant food, the maligned gas also plays a role in regulating water use by the world's forests. New research has uncovered an unexpectedly strong decrease in H2O uptake caused by increasing CO2. Along with global increases in photosynthesis, forest growth rates, and carbon uptake, higher CO2 levels contribute to enhanced timber yields and improved water availability. Who says higher CO2 levels are a bad thing?
Despite a decade and a half without temperature rise, climate scientists still stubbornly stick to their predictions of steadily increasing global temperatures. These predictions are all based on GCM, computer programs that model the circulation of Earth's atmosphere and oceans and a myriad of other factors in an attempt to simulate our planet's climate system. The problem is, the computer models are severely flawed, flawed at such a fundamental level that two climate modelers have called for a reassessment of all computer models currently in use. Sadly, a number of the flaws they point out have been known to scientists for decades, yet mainstream climate science continues to rely on these broken models, hoping to get lucky with predictions made for the wrong reasons.
The threat of widespread and persistent drought, ruining crops and threatening water supplies, is constantly cited as an outcome of global warming. Media talking heads, climate scientists (who should know better) and even the American President have all made this assertion—and there is nothing to back up the claim. Results presented recently at the annual assembly of the European Geosciences Union in Vienna show that forecasting drought is still beyond the reach of current climate models. Models run against historical data have either predicted periods of drought at the wrong times or missed them all together. Yet climate alarmists continue to spread this pernicious lie, preaching damnation with the certitude of an Old Testament prophet.
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.
For some reason a lot of people have become fixated on Antarctic ice—is it waxing or waning, accumulating or melting. Climate alarmists have striven mightily to show that ice at the poles in on the decline, melting in the face of rising global temperatures. Antarctica, with the largest store of glacial ice on the planet, is the primary focus of attention. If Antarctica’s ice sheets were to melt it would be a calamity for mankind. Unfortunately, Earth's climate system contains many cyclic trends, operating on decadal and longer periods of time. In the past, what some claim are clear trends have turned out to be only short term in nature. A new report, just published online, concludes that it is unclear if changes in atmospheric circulation over West Antarctica during the past few decades are part of a longer-term trend. In fact, ice cores reveal a significant increase in the oxygen isotopes from precipitation over the past 50 years, but the anomaly cannot be distinguished from natural climate variability.
Something happened this year that has become rare in recent times, much of the United States has had a white Christmas. As of December 28th, 64.4% of the US was covered by snow with an average depth of 6.2 inches (15.7 cm). This compares with last month's coverage of only 19.8%. My own town of Conway, Arkansas, received 10 inches on Christmas day and a winter storm advisory is in effect as another storm makes its way eastward. For Arkansas, this has been the snowiest Christmas ever, breaking the old record set in 1926, and the 7th snowiest day overall since 1875. But North America is not alone in feeling winter's bite—record cold continues in Siberia, while a vicious cold snap across Russia and Eastern Europe has claimed nearly 200 lives. What does all this say about global warming?
A new “comprehensive” report about the melting of Antarctic and Greenland ice sheets is being touted by climate alarmists as “grim news” but in fact says no such thing. This latest estimate, published this week in Science, combines data from many sources including 20 years of satellite data and 32 years of ice-sheet simulations to arrive at a mixed conclusion. It estimates that, between 1992 and 2011, the Antarctic and Greenland ice sheets lost 1350 ± 1010 and 2700 ± 930 Gt of ice, respectively. That is equivalent to an increase in global mean sea level of 11.2 ± 3.8 mm, less than 1/2 an inch. Moreover, while some areas were losing ice mass others were gaining mass from snowfall. The East Antarctic Ice Sheet (EAIS), which occupies over 75% of Antarctica, experienced mass gains during the final years of the study.
The Intergovernmental Panel on Climate Change (IPCC) has consistently predicted expanding world wide drought as one of the horrors of global warming. New research suggests that things may not be quite as arid as they predicted. According to scientists, a commonly used technique for estimating drought severity may actually overestimate the effects of dry spells. Revisiting historical data for the period 1980-2008, a new assessment technique found that the global area stricken by drought grew by approximately 0.08% per year—less than one-seventh (14%) the increase previously reported. Moreover, researchers found that drought causes higher temperatures, not the other way around. Once again, the horrendous effects of anthropogenic global warming have been found to be over hyped by the self-serving savants of the IPCC.
Earth's climate is controlled by the global balance of energy. Radiation from the Sun heats up the planet while heat energy is re-radiated into space through complex interactions of land, sea and air. The journal Nature Geoscience has just published an update about the balance that controls Earth's temperature and overall climate. Scientists conclude the global balance of energy flow within the atmosphere and at Earth's surface cannot be accurately measured using current techniques and is therefore uncertain. The current uncertainty in this net surface energy balance is an order of magnitude larger than the changes associated with greenhouse gasses. In short, previous estimates of climate change are invalid, swamped by fundamental uncertainty.
Climate change alarmists point to the past several decades of European weather to reinforce their claim that global warming has the continent in its grip. A new report shows that this recent warm spell is nothing abnormal or unprecedented—during the 1990s there was simply a return to conditions present during 1931-1960. The reason for the shift is warm ocean temperatures that are, in turn driven by variation in warm ocean currents from the tropics. The instrumental record shows that, relative to the average temperature of the rest of the world’s oceans, the temperature of the North Atlantic Ocean has fluctuated between anomalously warm and anomalously cool phases, each lasting several decades at a time. Palaeoclimate records suggest that similar variations extend much farther back in time. The observed pattern of multidecadal variation in North Atlantic sea surface temperatures (SSTs) has become known as the Atlantic Multidecadal Oscillation (AMO).
There has been a wave of triumphal announcements by climate change proponents recently, almost giddy over the summer shrinkage of the Arctic ice sheet. “Lowest level ever!” they proclaim, thought that is not quite true. Nonetheless, The Arctic pack ice has been receding over the last decade or so, but that is only natural. You see, there is a well known, if poorly understood, linkage between the ice at the north pole and the ice in and around Antarctica—and the ice around Antarctica is doing quite well. Satellite radar altimetry measurements indicate that the East Antarctic ice sheet interior increased in mass by 45±7 billion metric tons per year from 1992 to 2003. This trend continues today, reinforcing recent scientific investigations into this millennial scale oscillation between the poles. According to studies, this is how things have been for hundreds of thousands of years.
That large changes in solar radiation can affect Earth's climate is widely accepted. However, the hypothesis of solar-induced centennial to decadal climate changes, which suggests feedback mechanisms in the climate system amplifying even small solar variations, has not found acceptance among orthodox climate scientists. The climate change clique would rather place their money on greenhouse gasses—human generated CO2 in particular. It is true that satellite-based measurements of total solar irradiance show that mean variations during solar cycles do not exceed 0.2 W m−2 (~ 0.1% of the Sun's energy output). It has also been noted that relatively large variations of 5–8% in the ultraviolet (UV) frequencies can occur, though how this could change global climate remained a puzzlement—but perhaps no longer. From studying a significant climate shift 2,800 years ago, a group of scientists have concluded that large changes in solar UV radiation can, indeed, affect climate by inducing atmospheric changes.
Between 15 and 20 million years (Myr) ago, Earth's climate took a pause during its long slide into the Pleistocene Ice Age for a period of real global warming. During this relatively brief time glaciers around the world retreated and there are indications that, at least around the edges of the continent, there was significant vegetation on Antarctica. Temperatures may have been as high as 11°C higher than today. Scientists say this global warm spell took place under under CO2 levels in the range of 190–850 ppmv, both significantly higher and lower than today's 390 ppmv. It is hoped that studying conditions during the Miocene warming can provide constraints on the fundamental laws governing the climate system. Why? If the Pleistocene Ice Age is truly coming to an end, as some have said, this may be the climate of the future.