Global Climate Change

April 22, 2024

Part 1 of 3 Part Series

Is the Climate Changing ?

The easy answer is Yes.  The Climate has always changed and always will.

Unfortunately, the subject is characterized by misinformation.  On one hand, many in the major media broadcast a worst-case scenario, creating a fear factor that much of the population has adopted.  On the other hand, some are in denial of any change, or diminish its existence.  Perception is not Reality.

Global climate is a classic example of Variation which I discussed in my first post (Please Read).  Much of the public does not have the Perspective to evaluate the change, the magnitude, and the reasons for climate change.  A major issue is mankind’s effect on the current situation.

In this Part 1, I will present some history of Earth’s climate that we need for an expanded view of what happens with climate.  Using an objective basis, policymakers may determine what, if anything, mankind should do to ameliorate the effects on society.  One thing is certain, if the Global Climate wants to change it will proceed no matter what mankind does.

Let’s start with a look at Earth’s history from the beginning.  Since Carbon Dioxide is a greenhouse gas, this review includes components of the atmosphere as it has an effect on climate.

Earth’s Timeline

There are Five Major Eras with events summarized below.  The Eras are further broken down into Periods which are too many to cover for this discussion.  That would make a whole book.

O      Archeozoic Era       4.5 Billion – 1.5 Billion Years Ago 

-          The Earth solidifies from molten magma to rock on the surface.  (Earth’s core remains molten; hence we still have volcanoes).

-          Continental Plates (Tectonics) are formed.

-          Oceans form, or a barrage of asteroids deposit water, depending on different theories.

-          The Era starts with very little oxygen in the atmosphere. At one point the atmosphere is estimated at 15% Carbon Dioxide and 75% Nitrogen.

-          The Great Oxidation Event starts.  Research indicates that cyanobacteria produce mass amounts of Oxygen from photosynthesis.

-          The increase in Oxygen leads to a decrease of Methane in the atmosphere from a chemical reaction that produces Water and Carbon Dioxide, and may have cooled the climate.

-          The Huronion Glaciation coincides with a cooled climate – a global ice age period occurring 2.5 Billion to 2.2 Billion years ago.  Research says it caused a significant extinction of anaerobic organisms.

-          The Era ends with Oxygen Levels at about 10% of current levels.

O    Proterozoic Era       2.5 Billion – 542 Million Years Ago

-          Snowball Earth – another global ice age occurs 850 Million to 630 Millions years ago. 

-          More advanced Life develops as cells with a nucleus and organelles.

-          Evolution occurs from single cells to fungi, protists, plants, and animals.

-          Soft body organisms such as jellyfish appear near the end of this Era.

-          Oxygen levels increase significantly. 

-          Carbon Dioxide levels decrease as oxidation occurs from early photosynthetic life.

-          Content of the atmosphere changes to 35% Oxygen. 

O    Paleozoic Era        542 Million to 251 Million Years Ago

-          First hard structure species appear such as fish, coral, plant life, and vertebrates.

-          For reasons unknown, the Great Extinction occurs, which wipes out about 90% of all life forms.  (This was before the dinosaurs).

-          The continents form one consolidated continent called Pangea.

-          This may have caused a mass period of volcanoes which changed the Oxygen balance downward.

-          The Era includes the well-known Jurassic Period starting 201 Million Years ago.

-          The Period produces a dramatic change in life forms and climate, with large tropical plants, dinosaurs, and early mammals.

-          The Climate during the Era was much warmer and humid than today.

-          Average temperature at mid-latitudes were around 80 degrees F.

-          Average temperature at the poles were 40 – 50 degrees F.

-          With little ice at the poles, sea levels were much higher than today.

-          Carbon Dioxide levels were about 5 times higher than current levels.

O    Mesozoic Era      251 Million to 66 Million Years Ago

-          Supercontinent Pangea breaks up.  As continents move, so does local climate.

-          The Era ends with the Extinction Asteroid 66 Million Years ago.

-          Dinosaurs and many herbivores died off.  Small mammals survived.

-          The Asteroid impact initially caused a global winter from the debris in the atmosphere.

-          Worldwide fires drastically altered the atmosphere with consumption of Oxygen and creation of Carbon Dioxide.  This created a harsh environmental condition with Greenhouse gases and heat which played a role in the extinction of dinosaurs and other species.

O   Cenozoic Era    66 Million Years Ago To Today

-          The Age of Mammals ensues.

-          Early species of Humans evolve 2 – 6 Million years ago.

-          The Last Glacial Period, or the most recent Ice Age, starts 115,000 years ago and ends 11,700 years ago.

Summary

Global Climate History of Earth is marked by dramatic swings.  This is Variation demonstrated by the above major cooling/heating cycles, and changes in composition of the atmosphere.  Even mass extinctions.   And, the human race had no effect on this history, until lately.

Consider that the last Ice Age ended just 11,700 years ago.  To put this in Perspective, if the Earth were Ten years old, the Ice Age would have ended Yesterday.

There are numerous factors that cause Climate Change.  Influences include greenhouse gases, earth’s tilt and rotation, tectonic movement, and other contributors.

Now that mankind is a major environmental factor, what impact do we create?  And what are the plausible preparations, policies, and actions that we can take?

The next Two Parts of this Series will explore for answers.

David Hollaender