Global Climate Change - Part 2 - May 3, 2024

REVIEW OF PART 1.

We looked at the totality of Earth’s climate history over 4.5 Billion years.  It showed the giant Variations in temperature from hot to cold.  Major and Minor Cycles occur due to natural forces that affect climate.  From unlivable heat to “snowball” conditions, the Earth has swung through incredible changes in climate. 

The main point:  the Climate is always in a state of change (Variation).

You have heard information about Climate Change in unexplained bits at a time in the media.  Cogport will take a more comprehensive look so you can reach your own conclusions. 

This requires some examination of data, and I hope you are up for it.  With good information, you will have a better understanding of the issue.

INTRODUCTION - PART 2

In this Part, we analyze different time periods showing levels of GHG’s and Global Temperatures. 

These samplings provide some good indicators.  You will find some interesting (or entertaining) facts along the way.

We will review the current prevailing theory that Greenhouse Gases are the primary cause for Earth’s temperature variation.

DEFINITIONS

It is best to define terms and abbreviations at the start, so you can refer to them as you read.

O   Temperature: 

Stated in Degrees Fahrenheit (For example 70F).  Temperatures are stated as an Average of composite global temperatures (from around the globe and from pole to pole).  Historical Temperature data used in this article are estimates from scientific research such as geologic, ice cores, and fossil analysis.

Actual recorded thermometer data exist only for the last 170 years.

O   Greenhouse Gases (GHG):

Molecules in the atmosphere that have the effect of trapping heat in the atmosphere and warming the Earth.  There are several GHG’s that have this effect.  This article covers the three major ones:

Water Vapor (H2O)  (Yes, H2O is a GHG)

Carbon Dioxide (CO2):    The most prevalent GHG.

Methane (CH4):    A highly potent GHG.

O  Part Per Million (ppm): 

As used in the context of gases in the atmosphere, a unit of measure for a concentration of a gas measured as a ration to all other gases on a per million basis.  For example, one ppm of CO2 is compared to one million of all other gas molecules in the atmosphere.

O  Radiative Forcing:

A measure of the effect of GHG’s that trap solar heat on the Earth’s surface that would otherwise radiate back out of the atmosphere.  Positive Radiative Forcing leads to warming of the climate.   The Earth reflects about 30% of solar heat back to the atmosphere.

O  Tectonics

The change in position of the continents on the Earth’s surface.  The rate of change is 2 – 4 inches per year.  This does not sound like a lot, but over a very long period that adds up to major change.  It is driven by convection currents in the Earth’s mantle.

For example, the land mass of Alaska was positioned near the equator 250 Million years ago, in a tropical climate.  That was the time of Pangea when all continents were joined together.  It also explains why Alaska is drilled for oil produced from organic deposits of tropical foliage millions of years ago.

The rest of Part 2 covers the Atmosphere, ppm Levels of GHG’s, and Global Temperatures.

ATMOSPHERE – Baseline Totals

Total Atmosphere

Weight……   5.5 Quadrillion Metric Tons.

Troposphere    The Lower Atmosphere contains 80% of Earth’s air.

Volume……  10,077,000 Cubic Kilometers (212 Quintillion Cubic Ft).       

                           (For reference, 1 Quintillion = 1 Billion Billions). 

Weight……     4.4 Quadrillion Metric Tons.

Five Major Atmospheric Gases (excluding Water Vapor)

Nitrogen  (N2)……................. 780,840 ppm   (78%)

Oxygen  (O2) ………………..  209,640 ppm  (21%)

Argon  (Ar) …………..……….      9,340 ppm    (1%)

Carbon Dioxide (CO2) ……...          400 ppm     (0.04%)

Methane (CH4)…………….....              1.8 parts per billion    

KEY POINTS ON GHG’s

The immediate observation is that CO2 and CH4 are very small components of the total atmosphere.

From here, we look at their effect on Climate Change.

Water Vapor

Water Vapor varies significantly from 0.1% to 4% of the atmosphere depending on location and weather conditions.

It occurs naturally without significant impact from human activity.  So, there is not much that man can do to alter its concentration.

However, it is the most prevalent GHG and accounts for about 50% of the effect of all GHG’s.

As the climate warms, more water vapor is released to the atmosphere which is a compound effect of other GHG’s.

Carbon Dioxide (CO2)

CO2 is the second most common GHG with a high rate of radiative forcing that creates a warming impact.

Now starts the more data intensive part of this post.

Baseline Information On CO2 & Temperatures

In Long-term historical Perspective, we live in a period of very low ppm of CO2 providing global temperatures much lower than the historical average.   This has been a “Goldilocks” period – just right for homo sapiens to flourish.

Here is a Table comparing CO2 ppm and estimates of average global temperatures.

Time Period                                                     PPM                                    Global Temp (Fahrenheit)

70 Million years ago                                       1100                                            73

56 Million years ago                                       1700  (peak)                                85

2 Million years ago                                          270  (low – an Ice Age)             47

10,000 years ago                                             270   (last big Ice Age)              46

Year 1800 (from ice cores)                               284  (the ”little” ice age)            49

Year 1900                                                         290                                             53

Year 1958 (from Mauna Loa)                           313                                              57 

Year 1999                                                         367                                             58

Year 2010                                                         387                                             58

Year 2023  (El Nino year)                                 421                                             59

Observations:

The Long-term trend for 70 Million years has been a significant decline in CO2 and Temperatures. 

The last Ice Age 10,000 years ago was the most recent low Global temperature at 46F.

The last 5,000 years are still low on the Long-term trends in these measures.

Since 1900, ppm of CO2 has increased 45%.

Since 1900, Global Temperature has increased 11% to 59F.

The most recent increase is significant over a short time period.

Relationship Between CO2 Levels and Global Temperature

The following chart shows the up and down Variations (or cycles) of CO2 & Climate

                                                  Last 70 Million years to Now.

Observations:

The Chart shows a correlation between CO2 levels and Global Temperature.

The Long-term Trendlines are parallel and show the Earth falling in Temperature.

The chart shows a pivot point from downward to upward.

In 2023, the Temperature hit the Trend Line and is poised to continue in an Upward Cycle.

Here is another Chart that plots the Rate of Change in CO2 levels and Temperature.

Observations:

Again, a correlation exists between CO2 levels and Global Temperature.

The recent change in CO2 now puts its level at the top of the Chart.

This is an indication that warming on Earth will continue.

Methane

CH4 is a potent GHG with global warming potential (GWP) 84 times higher than CO2 over a 20 year time frame due to radiative forcing.

About 20% of climate change is attributed to CH4.

CH4 is also a major source of Water Vapor and CO2 through oxidation in the Stratosphere.

CH4 is primarily created by living organisms, including human activity.

While the concentration of CH4 may seem small, the impact is large due to its high index of Radiative Forcing. 

This Table compares CH4 level and Global Temperatures.

Time Period                                     Parts per Billion (ppb)                       Global Temp (Fahrenheit)

Year 1750                                          720   (the “little ice age”)                        49

Year 2023                                        1923                                                          59

Since 1750 (start of Industrial Revolution), CH4 ppb rose by 160%.

The Global Temperature rose by 20%.

SUMMARY

This climate data supports the prevailing theory that GHG’s are a significant factor in Global Climate Change. The correlations indicate that growth in GHG’s cannot be ignored.  They will affect future Temperatures.

The charts suggest that we have reached a turning point in climate cycles with higher temperatures predicted.  Just how much, science cannot exactly say.  But we should be preparing for change.

In Part 3, Cogport will review the sources of GHG’s and the impact of human activity.  We will discuss policies and practical actions that might be taken.

David Hollaender

cogport.com