In the 70s when I became a science editor at an academic publishing house, covers like the above were beginning to grace popular magazines. The light bulb went on in my head: Why not a book on this issue going into sufficient detail for people to grasp what is going on?
I contacted three different climatologists, each happy to talk with me and each patiently explaining why there could be no book.
- In the first place, we are currently in not one but two ice ages. An ice age occurs in one of earth’s hemispheres whenever that pole is ice-covered year-round and long-term.
- In the second place, the ice age in the southern hemisphere, the Oligocene ice age, commenced 30 mya when the South American plate broke free from the Antarctic plate and started its northward drift, in the process opening up the Drake Passage leading to formation of the Circumpolar Current, the planet’s largest and coldest.
- When the South American plate joined the North American plate 2.58 mya blocking the flow between the Atlantic and Pacific, we got the Quaternary ice age in the northern hemisphere, the one of greater concern as it affects large tracts of potential agricultural land suited to human habitation.
- Given that our exit from this situation depends on tectonic plate movements (which proceed at the speed of fingernail growth), we are likely to be in these two ice ages for many millions of years to come. Other ice ages in our past have lasted well more than a hundred million years.
- Antarctica is now stuck dead center over the South Pole and is likely never going anywhere again.
- No modeling offers a clear picture of what it will take for continental plates to reconfigure so as to end the Quaternary ice age.
- Our present Holocene epoch is part of our ice age, an respite from glaciation (by which is meant not glaciers but ice slabs covering land masses well down from the polar circle in the northern hemisphere).
Then they showed me this:
This is a reading of ice-core studies, which are only deemed accurate for 450 ky. This chart happens to be from Vostok, the Russian center on Antarctica. The one I was shown back in the day was Greenland ice, but the story was essentially the same.
Those pink-topped peaks are interglacial periods. That is our Holocene on the far right. You will see that it is cooler than prior interglacials, which has nothing to do with industrial COO but instead models, in addition to the ice melt chilling ocean currents typical of each interglacial’s onset, to a bolide strike that caused the Younger Dryas cooling for a millennium.
A few million Paleolithic members of our species peopled the Earth at the onset of our Holocene epoch, which was estimated to be near the carrying capacity of the planet during glacial conditions. Old stone-age man thrived on a high-protein diet as the cold-adapted fauna were slow and easily hunted while there was year-round refrigeration. Tribes were even able to put away food stores and firewood to survive in caves during frigid winter months. Mesolithic man, through the Younger Dryas, was on the brink of extinction, surviving only on fairly sessile foods—roots, mushrooms, turtles and such.
As the warm returned and grasslands replaced the tundra, Neolithic man was daunted by the fact that his more advanced atlatls and bows were still no match for the fleet species occupying the Steppes. We were reduced to eating grass, the seeds anyway, and to domesticating certain grassland species. Our genes had to undergo change before we could well-digest the grains and milk, but the eventual result was civilization.
As our Holocene draws to an end, we have as many billion people as we had million people at the start. As the paleo-climatologists I spoke with pointed out, when we return to glacial conditions any old time now, whether in two more decades or two more millennia, a new glacial period will dramatically cut growing seasons and lock up carbon dioxide in the ice and chilly waters, thereby returning us to a flora of conifers, lichens and other plant life edible only with four stomachs. The carrying capacity of our planet will return to some few million of us who will have no reason to cling sentimentally to the notion of civilization.
The only ray of light I see is that if we go back to Miocene conditions, the epoch before the Oligocene ice age which was the dreaded 5 °C warmer than now, it was a worldwide Mediterranean climate. How is that?
With two frozen poles, as now, heat gets trapped into tropical latitudes creating tropical hot spots. Our jet streams, north and south, then rocket around the planet redistributing tropical heat and polar chill willy-nilly. Get rid of the tropical heat and polar cold, and the jet stream simply redistributes balmy weather.
We could simply end all the restrictions on carbon output, except that all the hot air is coming from Al Gore and company, not carbon. Still, we could take all the funds wasted on creating a climate scare and plow it into finding a reasonable model for melting the poles and getting us out of an ice age, our future as a species will be a lot brighter.
Evolution: An Objective Look 