“It is one thing to show a man that he is in error, and another to put him in possession of the truth.” -John Locke

When one encounters the term “climate change” in the media, it is a shorthand phrase usually meaning Science has identified global warming as the cause of an impending climate catastrophe threatening humanity itself , manmade carbon dioxide emissions is the singular cause of that global warming, and the existential magnitude of the threat to our continuation as a species justifies even the most drastic and costly corrective policies. The proposed response to that alleged threat by national and global government bodies is truly massive in its scope, far more ambitious than simply adopting alternative energy sources. Is it the only response? Is it the best response? Is the scope of it necessary?

How can the average person make such judgements unless they have a clear understanding of the problem and our options, in all their dimensions and facets? Scant few of us are scientists. My view is one doesn’t need to be a scientist to understand this issue.

Common Sense Will Suffice

Whenever I write or comment online on this subject, the most common response is that what I say has no value because I’m not a climate scientist. In fact, I do have the credentials to read science research papers, but that is not at all what this essay today entails. Instead, I believe that common sense applied to a few widely accepted, non-controversial facts is sufficient to give clarity to this whole issue sufficient for the average person to make informed judgements. That is what the reader will find here, and that is my objective: clarity on the climate change issue in all of its dimensions, without diving into the weeds. My intention is not to show anyone the error of their beliefs, but rather to show how much clarity on the issue can be had by applying simple common sense to a few uncontroversial facts. With clarity, the readers can make up their own minds on the nature of the threat and on the options for our response to it.

The starting point of the science is the established fact that doubling the level of atmospheric carbon dioxide (CO2) in the atmosphere will raise the global temperature about one °C (just under two °F), which each successive doubling having less and less additional effect. That is well-researched and widely accepted science. The ending point of the UN Climate Change Agenda (as best can be determined) is, according to environmental and other economists, included Nobel Laureates, an accumulated cost of over eighty trillion dollars by the end of this century and a global economy by the end of the century supported, well or poorly, by non-fossil energy.

Between that starting and that ending point, there is a vast landscape of science, facts, hypotheses, theories, speculations, weather statistics; there also are the different policy alternatives; the national agendas and agreements subsumed within the umbrella of the climate change agenda; the corollary political agendas intending to be advanced by the climate agenda; the social and moral consequences on nations in poverty from policies that raise the price and lower the availability of energy; the allocation and redistribution of wealth which shapes the climate agenda and results from it; and the social and moral implications of all that wealth being no longer available for other urgent human purposes.

An open-minded and honest person can see that there is a great deal to be discussed without first having to deny proven science, and that acceptance of proven science alone does not lead inexorably to the complete proposed political climate agenda being advocated, in all its vast scope. The rest of this essay will be useless to anyone who disputes that point, so if you disagree, best you quit now and read something else.

An Existential Threat?

A great many real or potential threats do face humanity; I trust that is not a controversial statement. It’s prudent to want to mitigate the extent of those threats. The goal should be to do the right things for the right reasons. The right thing to do is the relief of preventable misery and death across the globe; the right reason is simple morality (and self-interest). We who are able do that must do that, to the extent we can, because of our shared humanity (and self-interest). I hope none of that is controversial, because that is basic to this writing.

Is climate change today an existential threat to humanity? It is being presented that way wherever one looks, but is it really? That question is where we will begin.

Where threats are complex, it is usually not at all clear what is the best course of action. Such is the case with the threat of changes in earth’s climate. What we do know for certain is that changes in climate have many times caused great disruptions in human societies, at times nearly causing our extinction as a species. But what is the situation today? What are the actual nature and extent of any threats from changing climate today? What are other kinds of threats to mankind, and is climate change greater or lesser than they are? Our best response to climate change requires clarity about the actual situation. Addressing the wrong problem or the right problem in the wrong way wastes resources and does little good.

Since the case is complex, I will break it down into six essays for easier digestibility and to keep the essays focused and manageable.

Essay 1: it’s happened before; it’ll happen again.

Essay 2: How has climate affected humanity in the past?

Essay 3: Why the climate changes is poorly understood.

Essay 4: Will the UN Climate Agenda achieve what it promises?

Essay 5: Is the UN Climate Agenda the best bang for the buck?

Essay 6: Is there a better way?

Since this article is presented in separate essays, I will arrange for only the last one to allow reader responses. I don’t want to debate every little thing.

Now that I have laid my cards on the table, I expect anyone who worships at the Church of Climate Change is half-way out the door. If you are open-minded, stay with me, you might enjoy the ride.


Essay 1: It’s happened before; it’ll happen again

Looking at human history, climate change has been the most drastic threat by far to our continued existence as a species. This essay will present some facts to back that statement up and give the reader a sense of the impact. The essay is a bit long because the story is just so compelling and interesting. I tried to shorten it, but everything I might leave out is needed for a fuller understanding of what changing climate can do to our lives, and everything links up with other sections later on.

Birthday in the Ice Age

To set the stage for this discussion, early humans arrived on earth during epochs of severe cold and ice. The global temperatures around two million years ago, before humans, were about what we enjoy today. Then began a descent into an age of ice which continued until about 10–11,000 thousand years ago. The decline happened over roughly 10,000 years, and the global temperature declined over thirty °F. We can draw solid evidence about the period back to about 400,000 years ago, and some evidence back about 740,000 years ago, from Antarctic ice cores, and even better evidence from Greenland ice cores back to about 120,000 years ago. Sea floor cores give evidence of climate over 2 million years, and in the 1950s sea cores were the definitive evidence for the existence of the Ice Age. Science also gathers evidence from many other kinds of sources. So we have some fair idea of the general geologic conditions in which humans lived. Most of the land area was and is in the Northern Hemisphere, and much of that was covered by glacial ice 2–3 miles thick. The climate was very dry and cold. Except in the tropics, it could be described as semi-arid tundra, grasslands and boreal forests, and in the tropics rainfall was about half what we know today. That world has been described as glaciers surrounded by deserts. That world is where humanity began.

It is important to note also that ocean levels were about 400 feet lower during the peak of Ice Age glaciations, meaning earth’s topography was quite different. Australia was connected to Asia by land through Indonesia, and Alaska was connected by land to Russia. North and South America were connected; Ireland and England were part of the European landmass. This aided human migrations at the time, such as the overland migration of East Asians into North America through Alaska 14,000 years ago. It has been calculated that about 11 million square miles of dry land was created by the falling sea levels caused by locking up water in the glacial caps. It is certain that that land was inhabited, although no evidence of it remains. There are many stone structures found on that land around the world, now under water, that some archeologists conclude were the result of human building, but that idea is very controversial. Such structures, if true, would predate Stonehenge by several thousand years; unlikely but possible.

Climate Stresses on Human Species

Neanderthal humans, the main human subspecies during the early to mid Ice Ages, were not at all the brutes commonly depicted, but rather a very successful subspecies. They left Africa, migrated as far as the edges of the Ice Age glacier caps, and survived in tough conditions. They had technology sufficient for their conditions. Neanderthal man explored and migrated to much of the reachable earth over their several hundred thousand years on earth. They survived some apocalyptic natural catastrophes that, combined with the conditions of ice age climates, decimated their numbers at times to an estimated 25,000 individuals, according to DNA studies; and in particular the climatic consequences of the explosion of the Toba super-volcano 70,000 years ago, occurring during the depths of Ice Age cold climate, reduced humans to an estimated 10,000 individuals total. Climate change and natural catastrophes like volcanism and asteroid or comet impacts caused humanity to hang on by our fingernails more than once. Neanderthals disappeared 30–40,000 years ago, not because we Homo Sapiens killed them off, but because we absorbed their few numbers into our greater expansion. Homo Sapiens simply out-reproduced Neanderthals. Everyone today whose ancestors migrated out of Africa long ago carries Neanderthal DNA at the 1–3% level.

At least four times over the age of humans, perhaps many more, the great glaciers retreated to a large extent in sudden and extensive global warming, lasting some few thousands of years, before each time the climate resumed ice age coldness. And perhaps it will again; who knows? In particular, around 130,000 years ago there was an interglacial warm period which melted all the glacial ice, even nearly all the ice on Greenland. We know that because only the oldest remnants of ice at the very bottom of the Greenland ice sheet are older than that. A graph will be found in the next essay showing that that interglacial period peaked at about nine °F warmer than temperatures today, before reversing back into Ice Age temperatures.

Numerous other sudden warmings have been documented, which no doubt caused some smaller extent of glacial retreat, always followed by sudden cooling and glacial growth. Charts in the next essay display dozens of such events, by no means all of them. No doubt these warm periods contributed to human recoveries, while the resumption of arid cold made life again difficult. Since we don’t know what caused the Ice Age, we can’t say those climatic drivers are gone for good.

The Age of Megafauna

By about 20,000 years ago, it is estimated the glaciers on North America were up to three miles thick, extending down to Ohio. The North American ice cap is estimated to have contained seven million cubic miles of water, and another three million cubic miles in the ice caps over Asia and Europe. The rest of North America was probably tundra, grassland and boreal forest, home to massive mammals and later some few humans. The seas off the coast of Georgia were probably thick with icebergs. Agriculture was impossible; hunt and gather or die.

It is known that rapid and extensive changes in environmental conditions accelerates evolution, and it is tempting to speculate that the conditions I have described contributed to the evolution of mammals of massive size. North America was home to mammoths and mastodons half again the size of today’s elephants; giant ground sloths the size of an elephant; cave bears three times the size of a grizzly; powerful saber tooth tigers; dire wolves, bison, camels and horses. The human population that migrated to North America hunted such animals, and were hunted by them. It may be that climate variability during the Ice Age influenced the evolution of the human species as well as these mammals.

The End of the Ice Age Glaciation

Ice core and sea floor core analyses detect many periods of sudden and large climate changes during the Ice Age after the appearance of humans, but the impact of all that on human society, while certainly of serious consequence, is little known. We can deduce quite a bit about the impact of the specific changes in climate that occurred around 14,000 to 10,000 years ago as the Ice Age was ending. That was a time of dramatic changes in the climate that eventually warmed the earth and melted the glaciers covering most of the Northern Hemisphere, leading to the warm Holocene Period in which we live today.

Those changes were kicked off about 14,000 years ago with an abrupt and extensive warming that then abruptly changed to dramatic cooling, indicating major instability and shifts in the climate. There followed other rapid warming and cooling periods of short duration. Around 12,000 years ago, an extremely rapid decline in temperatures, estimated from ice cores at nearly twenty °F decline in less than a century, was reversed by a nearly uninterrupted and rapid warming that finally ended the Ice Age. Clearly the climate was undergoing huge changes of unknown cause (unknown until 2008; more on that in Essay 3), which could be fairly called a transition into a new stable configuration. By 10,000 years ago, the glacial ice caps were about gone and the oceans had risen 400 feet in a great melting. At about the same time all this was occurring, nearly all the megafauna mammals went extinct in North America, except for the bison. The theory is that they could not cope with the stresses of the rapid degradation of the climate and changes in the landscape. There is some evidence that the Clovis humans of North America held on for a time, but were finally done in by an asteroid strike, smaller but similar to the one that did in the dinosaurs. There is a “black mat” layer across the continent containing elements found in asteroids, with Clovis fossils below but none above that layer. The unsurvivable double whammy.

Only in the last ten or fifteen years has science begun to get hard evidence of what changes in the climate brought about the end of the Ice Age, and I emphasize only begun.

Impact of the Great Melting

The big chill ended about 10,000 years ago, or about 8,000 BC. The ice sheets melted over a period of about 2,000 years, starting around 10,000 BC, from warming which started around 11,000 BC. These dates are approximate, but the magnitude of events over that short time is astounding. The oceans are 70% of the earth’s surface and their level was 400 feet below today. Nearly all that unimaginable quantity of water, calculated at ten million cubic miles, was frozen into glaciers on the land of mainly the Northern Hemisphere, and it all had to melt and flow back into the ocean over only two thousand years. That sounds like a long time, but the flows of water required to accomplish that stagger the imagination. To empty North America of seven million cubic miles of glacial melt, 3,500 cubic miles of water had to flow over the land back to the sea every year. That’s every year for two thousand years.

The Mississippi, which connects to the Ohio and Missouri, drains most of the central Northern US. Think of the flooding that happens now when the Mississippi gets double its normal water in heavy sustained rains. The flow rate required when the glacial cap melted is the equivalent of 35 times that much water every year for 2,000 years. There had to have been vast flooding inland. The Mississippi today removes 200 million tons of sediment per year; the flooding from the melting glaciers would surely have scoured much more than that and caused a much higher sediment load; at a minimum, though, an astounding 14 million million tons of sediments would have been scoured away from North America, mostly from our US landscape. Perhaps that is why central states like Indiana and Illinois are flat as billiard tables.

As one example of such water flows, consider the horseshoe of Niagara falls, half a mile wide and 170 feet high. Geologists found a similar feature in Washington state five miles across and 400 feet high, which implies more than twenty times the might of Niagara at that one place. Geologic evidence of flowing flood waters many hundreds of feet deep and miles wide are found in Idaho and Washington. The Missoula Flood down the Columbia River Gorge in Washington has been estimated between 2.5 and 4 cubic miles of water per hour as the 500 cubic miles of ancient Missoula Lake emptied catastrophically.

As one example of the scale of this, an 18,000 ton boulder was found 700 feet up the side of a canyon wall which was carved by flowing water. So the ice was deep enough to carve out a boulder of that size and weight, and during the melting of the glaciers, an iceberg large enough to float that weight was carried away, with the boulder, on the flood waters, which were so deep they could wedge that iceberg 700 feet up a canyon wall, where the boulder was deposited when the ice melted.

Now that geologists know what to look for, they are finding evidence of the magnitude of the impact all this melt water had on the landscape. The impact of all this water flow on life must have been catastrophic. Small wonder the megafauna went extinct.

[in the interests of common sense, please note that that quantity of ice, seven million cubic miles, is about the same as now resides on Antarctica and that continent is about the same size as the USA. It required 2,000 years of extreme heat energy (more on that later) and massive water flows to melt that much ice and drain it off North America in only two millennia. Remember that the next time you hear hysterical warnings of the dangers of Antarctica melting by the end of the century.]

Impact of Sea Level Rise

Similar but smaller scale dynamics were occurring in Europe and Asia. As the sea levels were rising 400 feet around the globe, many human habitations were submerged and the people forced inland. There are oral histories today of those floods among the aboriginals of Australia, to name just one society. To rise 400 feet in 2,000 years, oceans would have to rise six feet over the average 30 year lifespan of humans of the time, and continue doing that for around 70 generations. Many prehistoric peoples would have racial memories of the effects this had on dozens of past generations of their peoples. And this all happened roughly between 10,000 BC to 8,000 BC , when humans in some places were building societies and settlements and in other places were being washed away. It is no wonder that most all ancient human societies passed down myths and legends of great floods wiping out civilizations. A Great Flood is arguably the most common myth humanity shares. Underwater exploration is today looking for and finding stone constructions off the coasts on what was dry land during the Ice Age, possibly of human origin. Those great flood myths should be understood as actual histories of humanity.

Our Benign Holocene Period

Just as great cold stressed human civilization, and the changes at the end of the ice age were catastrophic to many humans, the following warmth of the Holocene Period, our modern age, was immensely favorable. Almost immediately humans developed agriculture and city-states, developed trade routes with distant civilizations, developed technology, higher forms of art, philosophy and astronomy that come with times of peace and freedom from want. Human numbers exploded. The area now the Sahara Desert was changed at the time to a lush, fertile area of great benefit to the humans who lived there. Iraq was literally a garden of eden, and speculation is that it was the biblical Garden of Eden.

Human history has never experienced a time of climate constancy, and our Holocene is no exception. 6,000 years in, another climate change of unknown cause made the Sahara the world’s biggest desert and emptied it of humans, and Iraq became an arid, sandy place. Time and again the Holocene climate abruptly plunged into cold, with consequences on crops, famines, warfare, only to warm again to the enrichment of human society. Most recently, that sequence of cold climate disrupting human tranquility played out in the Dark Ages, and again in the Little Ice Age, when over 10% of the human population of the Northern Hemisphere perished, while the Minoan Warming, the Roman Warming and the Medieval Warm Period were times of tranquility and human advancement. Speculation about how all that climate change came about has only in the last ten or fifteen years begun giving way to scientific evidence. A great deal remains unknown.

I will treat in the next essays how frequent, abrupt and extensive were the changes in climate in the past, and the state of knowledge about the causes and dynamics. The plain fact that science knows so little about what caused those changes nor the mechanisms of how they developed, nor what ended them and precipitated new climate conditions, only drives home the point that the climate is vastly more dynamic and complex than is commonly reported today. Regarding the many components of earth’s climate dynamo and the interactions among those components, science today often doesn’t even know what it doesn’t know. We can observe and measure much of what constitutes climate today, but the attributes we measure are the consequences of the climate dynamo, not how it works or what drives it. In many cases we have evidence that something happened, but not why.


* Humans have repeatedly been decimated and in places wiped out by a variety of climate and other catastrophes.

* At times, earth’s climate was so harsh that the global population of humans was reduced to an estimated 25,000 and even at one point to an estimated 10,000. Humanity certainly has repeatedly been an endangered species.

* At other times, the climate was so benign that human societies flourished and multiplied.

* The times of greatest stress are when the climate is abruptly and drastically changing to a different mode, like the onset or ending of Ice Age glaciations.

* Humanity lives at the whim of nature and it’s twin forces of climate and natural catastrophes. Climate change has been and can be again an existential threat as well as a gift to humanity.

Show your support

Clapping shows how much you appreciated Rick Fischer’s story.

The author has chosen not to show responses on this story. You can still respond by clicking the response bubble.