Comments on Yesterday's blog from a Geologist

Greetings, Aruna.  I follow you and yours with interest.  I would like to comment on Earth Changes from the vantage of my geology training for anyone interested.  In my younger years, before the modern Arctic and Antarctic research, we understood that there had been four great Ice Ages. Now, with the Antarctic and Greenland ice core studies conducted here in Denver, Colorado, we see that the Earth has very regularly moved into and out of Ice Ages for over a million years for which we have continuous data.  We are approaching another Ice Age, according to the data, in the very near "geologic" future.  The temperature fluctuations coincide with astronomical alignment of such things as planetary wobble, axis tilt, etc.  Over the last million years temperature has controlled the greenhouse gas (CO2, methane, etc.) levels. That changed in the late 1800's when CO2 levels began to rise in earnest due to human combustion, primarily of coal.  Isotope studies of the carbon in the atmosphere indicates it to be geologically old carbon, so we know it is from coal that was mined by humans.  This is to say, without a doubt. the present rise in CO2 is from human processes.  Significantly, these CO2 measurements were made at 14,000+ feet on Hawaii so the readings aren't contaminated by nearby industry, urban areas, or forested areas.

The scientific interpretation of this information is that humans were not the cause of CO2 rise prior to the Industrial Revolution, but they are now.  In the past natural temperature fluctuation controlled CO2 levels, not the other way around.  This is to say that we have natural Ice Age conditions returning at some point, but we are altering that scenerio for the time being with human induced warming. 

Another point to be made here is to say that "climate change" is the norm on this planet.  Life on this planet has adjusted many times throughout Geologic Time.  Life has changed a lot, but it has been very survivable throughout the Earth's history.  Now, however, for the first time we have billions of humans along with the biota.  Human migrations are largely the result of the economic hardship of living where the climate is not agriculturally productive.  Reasons for migrating cascade with political turmoil.  Across Geologic (Deep) Time cyclic sea level rise periodically forces relocation inland.  Animal, plant, and microbial disease populations are also forced into relocation from time to time.  We use the term, "invasive species" today to describe this natural relocation for survival. All of this our pubic has heard about.

What many humans are unaware of is that we are well into a "mass extinction event" that may rival what happened to the dinosaurs in the late Cretaceous.  It began approximately 50,000 years ago.  That is the time when humans began to leave Africa and spread across the planet.  That is the time when the mega-fauna largely vanished in the America's, Africa, Australia, Europe and Asia.  Did humans hunt and eat them all?  No, that would have been impossible.  In the America's, Australia, and elsewhere we have recently learned that many plant/tree-types began to change beginning approximately 50,000 years ago. What part did we humans play in these biotic changes observed?  Well, we began to "manage" the land.  Our land-use practices began to change the face of the planet.  It began with Native populations using fire to control the large animals.  That practice led to clearing land for agriculture as we shifted from hunters to gatherers.  Modern humans are very, very, good at altering the surface of this planet for our many perceived needs.  Lightening naturally started fires, but humans are very, very, good at burning grasslands and forests, plowing and cutting, spreading insecticides, etc.  Most "natural" vegetation we see today is not actually natural.  What has this meant to the biota of Earth? Extinctions and in great numbers, Mass Extinction.

Now we begin to see our predicament.  We humans have been altering the face of our planet by our actions for over 50,000 years.  It has crept up on us.  I like the analogy, 'It is as if we have been slapped with an animal fur, but now with our un-natural ramping-up of carbon dioxide levels, we are about to be hit with a fur that has wrapped inside it, an anvil.'

Can we do anything at this point? Well, yes we can, but will we?  We humans caused ozone depletion in our upper atmosphere allowing UV-light to strike the Earth's surface causing all sorts of problems for us surface dwellers, like skin cancer.  We changed our ways and the ozone problem is receeding.  We have found slight changes in tropical forest land use that have returned nearly lost land. There are many examples of small changes, by very small numbers of people, that have brought animals back from the verge of extinction. The American bison is one example.  The major highway to be built across Africa's Serengeti, cutting of animal migration routes, can be done with innovations that can permit the migrations to continue.  Win-Win. We humans can live with this planet and all its inhabitants...if we choose to.  If not, our own presence on this physical planet may end abruptly when the anvil hits us on the head.
Climate change is the norm.  We are only just beginning to experience this one.  If humanity can learn from this opportunity how to pull together for the benefit of all beings sharing this planet, we might have a chance of survival, when an even more catastrophic disaster heads our way requiring quick action.  We have a polar reversal underway; we have an asteroid making multiple close-orbits in the late-2020's; we have Yellowstone, a super-volcano, over-due for eruption (keep in mind that when Toba, another supervolcano, erupted the human population, world-wide, dropped to about 10,000 survivors); ...not to mention the human and biotic suffering brought on by "regular disasters" such as  tsunami's , earthquake's, hurricanes, tornadoes, floods, and the like.


This modern dilemma that we humans have created can be a learning opportunity.  Will we learn, help one another, and change our ways?  We can if we choose.

Wayne Pound
Colorado, USA

'We may quarrel with men sometimes about things on earth, but we should never quarrel about the Great Spirit. Chief Joseph, 1881

Related Subject Posts:
Changes - Birds and Fish
Nature - Birds and Fish