Understanding Carbon and Climate Change

The year is 2019 and the top ten warmest years in recorded history have occurred in the last 13 years!  Below is a step by step look at understanding the history of climate change, how carbon dioxide affects climate change with a sneak peak at the methane factor and how this could be the most challenging issue that humanity has ever had to deal with…

Understanding Carbon
Carbon dioxide (CO2) is an important trace gas in Earth's atmosphere. It is an integral part of the carbon cycle, a biogeochemical cycle in which carbon is exchanged between the Earth's oceans, soil, rocks and the biosphere. Plants and other photoautotrophs use solar energy to produce carbohydrate from atmospheric carbon dioxide and water by photosynthesis. Almost all other organisms depend on carbohydrate derived from photosynthesis as their primary source of energy and carbon compounds. CO2 absorbs and emits infrared radiation at wavelengths of 4.26 µm (asymmetric stretching vibrational mode) and 14.99 µm (bending vibrational mode) and consequently is a greenhouse gas that plays a vital role in regulating Earth's surface temperatures.

How CO2 warms
Sunlight enters the atmosphere as ultraviolet and visible light; some of this solar energy is then radiated back toward space as infrared energy, or heat. The atmosphere is 78 percent nitrogen and 21 percent oxygen, which are both gases made up of molecules containing two atoms. These tightly bound pairs don't absorb much heat. But the greenhouse gases, including carbon dioxide, water vapor and methane, each have at least three atoms in their molecules. These loosely bound structures are efficient absorbers of the long-wave radiation (also known as heat) bouncing back from the planet's surface. When the molecules in carbon dioxide and other greenhouse gases re-emit this long-wave radiation back toward Earth's surface, the result is warming.

Scientists also know that the extra carbon in the atmosphere is the very same carbon that comes from burning fossil fuels. By analyzing molecular variations called isotopes, researchers can trace the origin of atmospheric carbon. That's not to say that the climate is as simple as an actual greenhouse. Many factors influence global temperatures, including volcanic eruptions and variations in the solar cycle and Earth's orbit that alter the amount of sunlight reaching the planet.

But scientists know that volcanoes and the sun aren't to blame for recent climate change.

Volcanic carbon dioxide emissions have been, at most, a hundredth of human CO2 emissions since 1750. In addition, volcanic eruptions cause changes for short timescales of about two years, not the longer-term changes being observed currently. The sun is more complex, but researchers have found that the recent solar-cycle minimum (between 1986 and 2008) was actually lower than the previous two solar-cycle minimums (the sun moves between quiet minimums and active maximums about once every five years). If anything, recent solar activity should have resulted in cooling, not warming. Likewise, a 2012 study found that between 2005 and 2010, a period when solar activity was low, the Earth still absorbed 0.58 watts of excess energy per square meter, continuing to warm despite the lower level of solar energy going into the system.

History of Climate Change and the Cenozoic Era
Climate change is the greatest Earthly phenomenon there is! As our Earth's climates have changed - due to the variable levels of CO2 (among other gases) - throughout the Earth's history, we have witnessed a variety of unique global environments...

The ages of the dinosaur saw a climate very different than any other time period, lasting millions of years. Then 'something' changed and the Earth evolved to its present state. We are now living in what we call the Cenozoic Age or Epoch and it is classified as having the most varied life forms of plants and animals in the entire Earth's history! Pretty impressive!!!!

Ironically though, the Cenozoic Era has been a period of long-term cooling. After the tectonic creation of Drake Passage around 41 million years ago, when South America fully detached from Antarctica during the Oligocene period, the climate cooled significantly due to the advent of the Antarctic Circumpolar Current which brought cool deep Antarctic water to the surface. The cooling trend continued in the Miocene, with relatively short warmer periods.

When South America became attached to North America creating the Isthmus of Panama around 2.8 million years ago, the Arctic region cooled due to the strengthening of the Humboldt and Gulf Stream currents, eventually leading to the glaciations of the Quaternary ice age.

The fact that our world’s last ice age ended around 10 000 years ago, demonstrates quite efficiently, that since the age of the dinosaur, our Earth has been slowly cooling!

So this should impress upon any readers just how significant and magical climate change actually is and how carbon levels determine what species live or die.

The issue now facing humanity is the fact that our burning of fossil fuels and many other activities is affecting the dynamics of our atmosphere and our oceans. We have been feeding an aggressive climate change (unnaturally warming our planet) since the Industrial Revolution began almost 300 years ago!

PPM – Parts Per Million
Concentrations of CO2 in the atmosphere were as high as 4 000 parts per million (ppm) during the Cambrian period about 500 million years ago to as low as 180 ppm during the Quaternary glaciation of the last two million years.  During these massively long periods of the Earth’s history, fossil records show how plant species have changed, as well.  All life forms that live during each phase of the Earth’s history have evolved to live within these extreme high concentrations of CO2 and the low concentration of CO2.  The problems now faced by humanity are based on the facts that present day plants and trees cannot evolve and migrate fast enough to the changing climate zones that are shifting very rapidly.

Historically, climate zones shift and move across the surface of our Earth at a speed of 1km every 1 000 years.  This seems rather slow… but when you consider that the rate of change has increased to a speed of around 10km every 100 years (as evidence now shows) a clearer understanding of our problems becomes quite evident!

Estimates based on reconstructed temperature records suggests that the amount of CO2 during the last 420 million years ago was with 2 000 ppm highest during the Devonian (400 million years ago) and Triassic (220–200 Million years ago), with a few maximum estimates ranging up to 3 700 ± 1 600 ppm (215 million years ago). 

Global annual mean CO2 concentration has increased by more than 45% since the start of the Industrial Revolution, from 280 ppm during the last 10 000 years (since the last ice age) up to the mid-18th century to 410 ppm as of mid-2018. 

Some readers may remember that in the mid 90’s a climate action group known as 350.org began to warn us that if the parts per million concentration of CO2 in our atmosphere reached 350 that global climates would begin to change and shift.  Nearly 20 years later, we see that we have already surpassed these levels quite considerably!

The present concentration is the highest in the last 800 000 years and possibly even the last 20 million years. The increase has been caused by human activities, particularly the burning of fossil fuels and deforestation. This increase of CO2 and other long-lived greenhouse gases in Earth's atmosphere has produced the current episode of global warming. About 30–40% of the CO2 released by humans into the atmosphere dissolves into oceans, rivers and lakes, which has produced ocean acidification… and this is not good – at all!

The Earth is Greener
From a quarter to half of Earth’s vegetated lands has shown significant greening over the last 35 years largely due to rising levels of atmospheric carbon dioxide, according to a new study published in the journal Nature Climate Change.

An international team of 32 authors from 24 institutions in eight countries led the effort, which involved using satellite data from NASA’s Moderate Resolution Imaging Spectrometer and the National Oceanic and Atmospheric Administration’s Advanced Very High Resolution Radiometer instruments to help determine the leaf area index, or amount of leaf cover, over the planet’s vegetated regions. The greening represents an increase in leaves on plants and trees equivalent in area to two times the continental United States.  That’s huge!

Green leaves use energy from sunlight through photosynthesis to chemically combine carbon dioxide drawn in from the air with water and nutrients tapped from the ground to produce sugars, which are the main source of food, fiber and fuel for life on Earth. Studies have shown that increased concentrations of carbon dioxide increase photosynthesis, spurring plant growth.

However, carbon dioxide fertilization isn’t the only cause of increased plant growth—nitrogen, land cover change and climate change by way of global temperature, precipitation and sunlight changes all contribute to the greening effect. To determine the extent of carbon dioxide’s contribution, researchers ran the data for carbon dioxide and each of the other variables in isolation through several computer models that mimic the plant growth observed in the satellite data.

Results showed that carbon dioxide fertilization explains 70 percent of the greening effect, said co-author Ranga Myneni, a professor in the Department of Earth and Environment at Boston University. “The second most important driver is nitrogen, at 9 percent. So, we see what an outsized role CO2 plays in this process.”

About 85 percent of Earth’s ice-free lands is covered by vegetation. The area covered by all the green leaves on Earth is equal to, on average, 32 percent of Earth’s total surface area - oceans, lands and permanent ice sheets combined. The extent of the greening over the past 35 years “has the ability to fundamentally change the cycling of water and carbon in the climate system,” said lead author Zaichun Zhu, a researcher from Peking University, China, who did the first half of this study with Myneni as a visiting scholar at Boston University.

Every year, about half of the 10 billion tons of carbon emitted into the atmosphere from human activities remains temporarily stored, in about equal parts, in the oceans and plants. “While our study did not address the connection between greening and carbon storage in plants, other studies have reported an increasing carbon sink on land since the 1980s, which is entirely consistent with the idea of a greening Earth,” said co-author Shilong Piao of the College of Urban and Environmental Sciences at Peking University.

While rising carbon dioxide concentrations in the air can be beneficial for plants, it is also the chief culprit of climate change. The gas, which traps heat in Earth’s atmosphere, has been increasing since the industrial age due to the burning of oil, gas, coal and wood for energy and is continuing to reach concentrations not seen in at least 500,000 years. The impacts of climate change include global warming, rising sea levels, melting glaciers and sea ice as well as more severe weather events.

And then there’s the methane angle on climate change….
What is methane?
Methane is a gas made up of one carbon atom and four hydrogen atoms. It's the same natural gas that some people use to heat their homes, and it also exists naturally in the atmosphere. Scientists worry that if methane increases in the atmosphere, it could cause even more warming than carbon dioxide from the burning of fossil fuels. Although there is much less methane in the atmosphere than carbon dioxide, it traps heat about twenty times as efficiently as carbon dioxide.
What are the sources of methane in the Arctic?
There are two potential sources of methane in the Arctic. The first source of methane is called methyl clathrate. Methyl clathrates are molecules of methane that are frozen into ice crystals. They can form deep in the Earth or underwater, but it takes very special conditions, with high pressure and low temperature, to make them. If the temperature or pressure changes, the ice that imprisons the methane will break apart, and the methane will escape. We're not sure how much methane is trapped in methyl clathrates, or how much is in danger of escaping.
The other major source of methane in the Arctic is the organic matter frozen in permafrost. The organic matter in permafrost contains a lot of carbon. It is made of dead plants and animals that have been frozen deep in permafrost for thousands of years. As long as this organic matter remains frozen, it will stay in the permafrost. However, if it thaws, it will decay, releasing carbon dioxide or methane into the atmosphere. This is why permafrost carbon is important to climate study.

How much carbon is stored in frozen ground?

There is a huge amount of carbon stored in permafrost. Right now, the Earth's atmosphere contains about 850 gigatons of carbon. (A gigaton is one billion tons—about the weight of one hundred thousand school buses). We estimate that there are about 1,400 gigatons of carbon frozen in permafrost. So the carbon frozen in permafrost is greater than the amount of carbon that is already in the atmosphere today. That doesn't mean that all of the carbon will decay and end up in the atmosphere. The trick is to find out how much of the frozen carbon is going to decay, how fast, and where.

What will happen to the frozen carbon if permafrost thaws?

When permafrost thaws, the frozen organic matter inside it will thaw out, too, and begin to decay. It's like taking a bag of frozen broccoli out of the freezer and putting it into the refrigerator. Once it thaws, it will eventually decay and break down.
As organic matter decays, it gets eaten up and digested by microbes. The bacteria that eat it produce either carbon dioxide or methane as waste. If there is oxygen available, the microbes make carbon dioxide. But if there is no oxygen available, they make methane. Most of the places where methane would form are the swamps and wetlands. And there are many miles of wetlands in the Arctic. When you walk around in the Arctic tundra, it's like sloshing through a giant sponge.
When permafrost carbon turns into methane, it bubbles up through soil and water. On the way, other microorganisms eat some of it. But some methane makes it to the surface and escapes into the air.

How will additional methane from permafrost affect global warming?

There are several opposing processes at work, which make this a hard question to answer. Warmer temperatures mean that permafrost can thaw and release methane to the atmosphere. But warming also means that the growing seasons in Arctic latitudes will last longer. When the growing season is longer, plants have more time to suck up carbon from the atmosphere. Since carbon in the air is what plants use to grow, it can also act as a sort of fertilizer under certain conditions. Then plants grow faster and take up even more carbon. Right now, the Arctic takes up more carbon than it releases. This means that plants take up carbon during the growing season, but do not release as much carbon through decay. So we say that the Arctic acts as a carbon sink.
But if the Earth continues to warm, and a lot of permafrost thaws out, the Arctic could become an overall source of carbon to the atmosphere, instead of a sink. This is what scientists refer to as a "tipping point." We say that something has reached a tipping point when it switches from a relatively stable state to an unstoppable cycle. In this case, the Arctic would change from a carbon sink to a carbon source. If the Arctic permafrost releases more carbon than it absorbs, it would start a cycle where the extra carbon in the atmosphere leads to increased warming. The increased warming means more permafrost thawing and methane release. This is what people refer to as runaway climate change and this is the point that could make any hopes for our future unobtainable!
What then, are the first steps we need to take in rectifying this situation?  We need to channel our energies into something positive to work towards, a vision of something worth believing in!  We no longer need to be scolded and made to feel ashamed for the way we have been living our lives.  We need more than a vision of doom!  We need a role to play that will influence others to aspire to a deeper level of understanding and action!!
Stopping pollution is not inspiring!  Cutting down on fluorocarbons is not inspiring!  Sorting your trash is not inspiring!  But thinking of ourselves in a global community being at one with our world is a dream of peace and action worth aspiring to.
Humanity needs a central organizing principal!  In order to create this, we need to secure widespread agreement that we need a central organizing principal and the way such a consensus is formed is especially important because this is when priorities are established and goals are set.
Historically, such a consensus has been secured only with the emergence of a life-or-death threat to the existence of society, itself.  This time, however, the crisis could well be irreversible by the time its consequences become sufficiently clear to congeal public opinion…. if not panic!
It is essential that we refuse to wait for even more evidence about how our lives are affecting our Earth’s ecosystems!  It is essential that we begin to immediately catalyze a consensus for this new central organizing principal.
Adopting a central organizing principal – one agreed to voluntarily – means embarking on an all-out effort to use every policy and program, every law and institution, every treaty and alliance, every tactic and strategy, every plan and course of action – to use every means to halt our destruction of our environment and to preserve and nurture our ecological systems.
Minor shifts in policy, marginal adjustments in ongoing programs, moderate improvements in laws and regulations are all rhetoric offered in lieu of genuine change!  These are forms of appeasement designed to satisfy the public’s desire to believe that sacrifice, struggle and a wrenching transformation of society will not be necessary.
By adopting a new central organizing principal, humanity will become empowered by a new way of thinking!  We can, without question, succeed in an all-out effort to save our environment.  But this effort will require an even deeper respect on the part of governments for the political and economic freedom of individuals.  It will also require dramatic measures to ensure that individuals are given both the information to comprehend the enormity of the challenge and adequate political and economic power to be true stewards of the places where we live and work.
2019 is the year when Canadians can make a difference!
2019 is the year when we understand that….

2019 is the year when we need to…

Devon is almost 8 years old… and he understands this!  

I hope that you can, too!!!

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