World Climate. Terje Instefjord
1 Preface
The awareness that the Earth's climate is changing is slowly growing, even outside the ranks of the most eager environmentalists.
Despite this growing understanding, many decision makers, with some honorable exceptions, still tend to express mostly verbal support, but are reluctant to back the necessary corrective actions required to avoid further deterioration of the climate.
Other debaters participating in the ongoing climate discussions tend to use arguments more based on their own personal conviction, than on available facts. With such a perspective, it is easy to argue for a wait and see strategy, where necessary, but often unpopular, decisions are postponed indefinitely, or at least until after the next election.
Contrary to widespread assumptions, we have sufficient knowledge today about both the current and historic climate to calculate the impact that the CO2 (Carbon Dioxide) content in the atmosphere has on the earth's climate.
In this book, known climate data from different time periods within the last 20 million years of the earth's history has been used to derive new mathematical formulas describing this impact.
All data used are historic data from before human activity began to affect the climate. The data has been taken from publications and magazines available on the internet, and should be well known for the informed reader. References have been provided to simplify source check.
I hope the new formulas describing the relationships between the CO2 content in the atmosphere, temperature and sea level derived in this book can help remove at least some of the uncertainties that weaken the understanding of the environmental challenges we face, and have to meet.
When using the new formulas to calculate values for temperature and sea level for given levels of CO2 content in the atmosphere, the results accurately matches observed historic values.
In spite of this, there can be conditions or relationships I have overlooked or that could have been better explained.
If you find anything you consider wrong, or that could have been better explained, I would appreciate your feedback to [email protected].
This book is divided into three separate parts.
In chapter 2 – 4, mathematical formulas describing the relationships between the CO2 content in the atmosphere, temperature and sea level are derived.
In chapter 5, possible rate of change scenarios for temperature and sea level are discussed.
Chapter 6 shows how the predicted temperature and sea level rise can be halted, and even reversed.
Best wishes with the reading.
2. The CO2 Greenhouse Gas
CO2 is not the only greenhouse gas that contributes to the greenhouse effect.
Water vapour and methane are two other important contributors.
The different greenhouse gases affect each other in different ways. For CO2, the following relationships are of special importance:
The more CO2 in the atmosphere, the higher the temperature.
The higher the temperature, the more water vapour and methane will accumulate in the atmosphere.
Parts of the greenhouse effect attributed to CO2 in this book will therefore be secondary effects caused by increased levels of water vapour and methane, caused by increased levels of CO2.
Since the root cause for these secondary effects is the change in CO2 content, the contributions from these secondary effects are included in the term "CO2 related" greenhouse effect used in this book.
The total amount of methane and water vapour in the atmosphere is determined not only by the amount of CO2, but also a number of other conditions and processes. Discussion of these conditions and processes is outside the scope of this book.
The CO2 content of the atmosphere is normally indicated in ppm (parts per million). This unit of measurement is also used in this book.
One ppm is equivalent to 1/000 of one thousandth (‰). (1,000 ppm equals 1‰). Today's CO2 content in the atmosphere of 400 ppm can therefore also be set as 0.4‰.
This is a very low concentration; however, since CO2 is a very efficient greenhouse gas, even a small increase in the amount of CO2 will result in significant climate changes.
3. What We Know
The new formulas describing the relationship between CO2 content in the atmosphere, temperature and sea level are derived using climatic data from different time periods within the last 20 million years.
All data used have previously been published in acknowledged papers, and should therefore be well known. References are provided to simplify source check.
To ensure human activity does not affect the results, all data used are from time periods when the climatic effects of the man made increase in atmospheric CO2 content were still insignificant or non existing.
Climatic data from the following time periods are used:
1) Pre industrial (50 years ago, 1967)
2) The ice ages
3) Prehistoric periods of warmer climate (3-4 & 20 mill years ago)
3.1 Pre Industrial Conditions
The first reference point used is the climate 50 years ago, 1967, when the climatic effects of the man-made increase in atmospheric CO2 content were still insignificant.
As shown in Figure 1 below, (Source: National Snow and Ice Data Center, NSIDC), (Ref 1), the 60's were also the last period of what was previously "normal" ice extent in the Arctic.
As shown in the same figure, today's ice extent, especially the summer extent, is significantly less than 50 years ago.
Figure 1 Ice extent in the Arctic from 1850
As shown in Figure 2 below, the global temperature increase from the 80's coincides with the decline in the summer ice extent.
Figure 2 Global temperature variations from 1880
If all current land based ice, mainly in Antarctica and Greenland should melt, the sea level would rise by 65 - 75 meters, depending on sources. (Ref 2) In this book, an average value of 70 meters is used.
3.2 The Ice Ages
The second reference point used is the Ice Ages.
From the Antarctica ice sheet, ice samples have been collected that show the climate over the last 800,000 years. These samples show that during this period there have been a number of relatively equally cold ice ages, separated by periods of warmer climate, with each ice age / warmer climate cycle lasting about 100,000 years.
The samples show that during the coldest periods of each ice age the CO2 content in the atmosphere was around 200 ppm, the average temperature was approx. 6˚C lower than now, and the sea level was approx. 120 meter lower. In the warmer periods between the ice ages the CO2 content in the atmosphere rose to approx. 300 ppm. (Ref 3 & 4).
What caused the ice ages is still uncertain. One theory supported by many scientists today is based on variations in the Earth's orbit around the sun. Three different cycles have been identified, with periods of 20, 40 and 100,000 years. (Ref 5). During these cycles the distance from the sun and / or the angle of the Earth's