65 – Understanding the CO2 Issue

Through the Spacefaring Institute™, a series of five videos on the Spacefaring Institute YouTube® channel are being posted focusing on energy and environmental security explaining why the United States should undertake an orderly transition from fossil fuels to space-based solar energy.

The first video, “Understanding the CO2 Issue”, addresses the environmental security risk arising from the abnormally high and increasing level of atmospheric carbon dioxide or CO2. I believe that the uncertainty as to whether this abnormally high level will bring harm to human civilization is a risk that should be addressed.

This 13-minute video addresses these topics:

  • What is carbon dioxide and where does it come from?
  • How has the carbon dioxide level changed?
  • What happened over the last 18,000 years as human civilization got its start?
  • What happened as the industrial age took hold?
  • What to do now?

The video includes charts showing the historic and changing CO2 levels.

The script of the video follows:


Atmospheric carbon dioxide, or CO2, levels are now about 40 percent higher than what has been normal for the last 800,000 years. While some climate scientists issue dire warnings, others express no concern. Yet, the abnormally high and climbing level of carbon dioxide is most likely due to human civilization and the growing human population. This Spacefaring Institute video discusses:

  • What is carbon dioxide and where does it come from?
  • How has the carbon dioxide level changed?
  • What happened over the last 18,000 years as human civilization got its start?
  • What happened as the industrial age took hold?
  • And, what to do now?

Part A – What is carbon dioxide?

Carbon dioxide is a molecule formed from one carbon atom and two oxygen atoms. It is produced naturally in many ways, including volcanoes, geysers, and hot springs. The decomposition of organic material in the soil. The respiration of animals, sea creatures, and microorganisms using oxygen and sugars to produce the energy needed to live. Natural forest fires. And the dissolving of minerals and rock, such as limestone, from contact with water. Plants use photosynthesis to extract carbon from carbon dioxide to form plant materials. In the process, oxygen is liberated back into the atmosphere and water to complete the cycle of life. In the atmosphere, carbon dioxide is an odorless and invisible gas while, in water, it exists as a dissolved gas. Carbon dioxide moves between the atmosphere and the ocean by wind and wave action. In a dry atmosphere, carbon dioxide now comprises about zero point zero four percent of the air or about 400 parts per million by volume. Nitrogen comprises about 78 percent while free oxygen comprises about 21 percent with the balance from other gases. Not just another gas, carbon dioxide, along with oxygen, are what make life possible on the Earth.

Part B – How has the CO2 level changed?

The Earth’s climate has changed due to natural causes. These may include slight changes in the sun’s output, slight changes in the Earth’s orbit about the sun, and the movement of the continents. Changes in the climate, particularly during ice ages, impact the carbon dioxide levels. Surprisingly, the Earth is now experiencing an ice age that began almost 2.6 million years ago. Over the last 800,000 years there have been, at least, eight cycles of glacial cooling, when glaciers grew, and interglacial warming when glaciers melted, as many still are today. On these glaciers, when snow accumulates, air pockets form. In Antarctica, Greenland, and other permanently cold places, over time the snow compacts into ice retaining the trapped air in tiny bubbles. Using cores of ice drilled from old glaciers, the composition of the air trapped up to 800,000 years ago has been measured and can be plotted. This chart shows the carbon dioxide variation over the last 400,000 years, from a low of about 185 parts per million during the colder glacial periods to a high of about 285 parts per million during the previous warmer interglacial periods. This natural variation, shown by the red band, was when the human population was small and human-produced carbon dioxide was negligible.

Part C – What happened over the last 18,000 years?

The last glacial cooling began about 150,000 years ago and created glaciers covering much of North America. The transition to the current interglacial warming began about 18,000 years ago. The carbon dioxide level, at the start of this transition, was about 190 parts per million and climbed to about 270 parts per million by about 11,000 years ago. From then until the beginning of the industrial age around 1700 AD, the carbon dioxide level climbed slowly to about 280 parts per million. During this time, the human population increased from about five million, 11,000 years ago, to about 640 million by 1700 AD. A key aspect of the emergence of civilization was the use of fire for more than just campfire cooking and heating. By roughly 9000 years ago, fire was being used to convert limestone and seashells into lime mortar and clay into pottery. About 6,500 years ago, the metal age began with copper being the first metal to be smelted. By the time of Julius Caesar’s Rome, about 2000 years ago, iron and steel weapons were common as was building with fired brick and concrete containing lime mortar. Throughout this period, wood and charcoal made from wood were the primary fuels. Like farming, the controlled use of fire has played a primary role in the emergence and growth of civilization for most of the last 9,000 years. With this in mind, the growing human population, the increased land use for agriculture and pasture, and the increased use of fire can, possibly, be seen as the cause of carbon dioxide levels slowly rising starting about 6,500 years ago.

Part D – What happened as the industrial age took hold?

The next technological leap forward in the use of fire did not occur until the early 1700s. Water wheels, providing mechanical work to replace humans and animals, had finally come into common use by around 1000 AD. Thirty-five generations later in 1712, Thomas Newcomen invented the first practical steam engine used, initially, to pump water from mines. Simple in concept, it converted thermal energy into mechanical work replacing the need for waterwheels or for human and animal labor where water power was not available. This invention, significantly improved by James Watt in the later 1700s, jump started the industrial revolution by using a simple fire to produce mechanical work almost anywhere. However, with the growing use of steam engines, the demand for wood fuel increased. By the mid-1800s, wood fuel supplies became scarce and coal was becoming the primary fuel source. This is seen in the famous 1869 photograph of the completion of the first American Transcontinental Railroad where the locomotive on the right, from the east, burned coal while the one on the left, from the west, where wood was then still plentiful, burned wood. The shift to fossil fuels, combined with the increasing population, the loss of forest cover, and a rising per capita use of energy, increased the release of carbon dioxide into the atmosphere. The atmospheric carbon dioxide level that had, by 1700, already reached the upper extent of past natural variations, continued to rise. Currently, with the world population above 7.4 billion, the level has reached 400 parts per million, 40 percent higher than normal, and is still increasing each year.

Part E – What to do now?

A key point to keep in mind is that out of the roughly 500 generations since the start of human civilization, our scientific awareness of the abnormal rise in the atmospheric carbon dioxide level, most likely due to the growing impact of human civilization, has only emerged in the last couple of generations. But with this awareness comes a responsibility to our children and grandchildren to act responsibly. Whether the abnormally high and still rising carbon dioxide level will cause significant environmental harm to human civilization is not known with certainty. Yet, for reasonable people, this uncertainty constitutes an environmental security risk that must be addressed. When high-pressure steam engines first came into use, for safe operation a pressure relief valve and a speed governor were found to be necessary to keep the engines operating within safe limits. It appears that human civilization has now caused the carbon dioxide level to be above the normal maximum level seen during previous warmer interglacial periods. We have a responsibility to return this level to normal. Hence, without impacting our western standard of living or preventing impoverished humans worldwide from improving their standard of living, we need to move responsibly, but in an orderly manner, to replace fossil fuels with sustainable energy as an important first step in returning the carbon dioxide level to normal.

Do you agree?