A Practical Understanding Of Climate Change: Part 1

While vacationing in Exuma, I met a family from Buffalo, New York, headed up by Michael Patterson, a retired engineer. Michael is a graduate of Penn State University and has been since 1982 a consulting environmental engineer. Even in retirement he continues to engage reporters and politicians about climate change, a subject we spoke about over the week we were together. Michael shared his take on global warming, its causes, and our responses. When he returned to Buffalo, he sent me two well-presented Q&As on climate change of which the first I am sharing today.

I hope you find it clarifies climate change issues and gives you practical advice on how we collectively can mitigate the risk and adapt to the changes we and subsequent generations will face. As always your comments and questions are welcome.

Q: How do Earth’s surfaces stay warmer than the cold vacuum of outer space?

A: By absorption of the extremely hot radiation from the Sun. We feel it when we stand outside on a sunny day. Our skin warms and emits radiation to the surrounding area. If it didn’t, we would continue to heat up.

Q: What keeps ocean surface water from freezing?

A: The gas molecules located in warm air above the ocean surface. This layer of air forms the Troposphere. As the air warms, clouds form and rise to the top of the Troposphere.

Q: What is special about these gas molecules?

A: These molecules are non-condensable and have at least three atoms. At ground level, nitrogen (N2) and oxygen (O2) molecules have only 2 atoms and are 96% of the molecules contained in the Troposphere. Argon (Ar) with one atom represents
1% of the molecules. Water vapour amounts to up to 3% of the total. When water vapour condenses, we feel humidity and get precipitation.

Q: How do special gas molecules with more than 3 atoms become warmer than Earth’s surfaces?

A: By absorbing the radiated heat coming from the ocean, sea, forest, field, and desert surfaces.

Q: How does this miniscule concentration of special molecules warm other molecules in the Troposphere?

A: By agitating them and causing them to collide, creating a chain reaction.

Q: Are Earth’s surfaces warming at an alarming rate?

A: Yes. The rate has increased to 0.2 Celsius (0.36 Fahrenheit) degrees per decade. The result is that mountain glaciers are continually receding, polar ice caps are melting faster, and Arctic Ocean sea ice is thinning.

Q: Should humans be alarmed?

A: Yes. By the year 2050, we may experience a mean atmospheric temperature increase of 0.55 Celsius (1 Fahrenheit) degrees of warming.

Q: According to NASA, what gases contribute to the warming of our Troposphere? 

A: Carbon dioxide (CO2) contributes 45%, methane (CH4) 20%, and nitrous oxide (N2O) 3%.

Q: What is the current concentration of CO2 in the Troposphere?

A: The present value from NOAA’s Mauna Loa observatory in Hawaii is 425 CO2 molecules per million (ppm). That means CO2 molecules are 0.000425% of the atmosphere. That doesn’t seem like a lot but in 1800, CO2 molecules represented a much smaller number, probably closer to 300 ppm.

Q: Why are there more carbon dioxide molecules in the Troposphere today than in our recorded past?

A: Humans are burning too much fossil carbon (coal, crude oil, and high-pressure natural gas).

Q: Define the term “too much.”

A: Too much occurs when living plants cannot photosynthesize the CO2 we humans are creating.

Q: Which plants are important?

A: Trees are important because they can grow continuously for 50 to 1,000 years, ingesting the CO2 and storing it by turning it into wood.

Q: How many trees are we cutting down each year?

A: The approximate total is 15 billion. When a tree is cut down, the CO2 sequestered in it can reenter the atmosphere if burned or left to rapid decay. If decomposition is slow, the CO2 gets released more slowly. If the wood is used for construction and furniture, the CO2 remains stored. Finally, some of the tree’s carbon from roots and leaves gets stored in the soil.

Q: What is the rate of human population growth and why is this relevant to the issue of climate change?

A: In 1961 there were 3.1 billion of us. The present number is surpassing 8.2 billion and increasing 65 million every year. The more of us there are the more energy we demand. The more energy we demand, the more CO2 we produce from fossil carbon.

Q: What is fossil carbon?

A: Fossil carbon consists of coal, oil and natural gas.

Q: Why are humans burning so much fossil carbon?

A: We use the energy from fossil carbon to power machines, manufacture things, other industrial activities, the heating and cooling of buildings, transportation and the generation of electricity.

Q: Are disturbances from heating in the Troposphere causing weather changes?

A: Yes. Most noticeable are the changes to atmospheric currents known as Jet Streams. These exist near the poles and in the tropics. They are located in the upper Troposphere and move at speeds of up to 160 kilometres (100 miles) per hour. These Jet Streams are becoming distorted from atmospheric heating and are contributing to increased severe weather events.

Q: Is warming of the lower Troposphere causing more drought?

A: Yes. NASA satellites continually monitor groundwater and soil moisture content with notable trends showing some areas of the planet experiencing increasing drought episodes.

Q: Will it be difficult for humans to stop burning so much fossil carbon?

A: Yes. This requires humans to change how we support our way of life.