Now substitute gasses in the atmosphere for the glass, and you can see how the effect of human activities warms the earth. A warm earth is a good thing. It is why life flourishes on this planet. Problems creep into the system when humans unintentionally play with the thermostat.
Fig. 11.1. Illustration of the greenhouse effect. (Modified from image by iStock Photo/DavidSzabo.)
PEOPLE WHO LIVE IN GLASS HOUSES SHOULDN'T THROW CARBON
One of the atmospheric gasses is carbon dioxide (CO2), an all-star in the greenhouse heating game. It absorbs energy, mostly infrared energy, from the earth's surface and emits energy back down to the surface. Needless to say, the more CO2 in the atmosphere, the more energy gets beamed back down to the earth's surface.
Both natural and human-made components create carbon cycles that shoot CO2 into the atmosphere. By itself, the natural carbon cycle can lead to net cooling or heating. But in the last century, human activities have spiked the concentration levels to the point where now there is only warming. Humans release excess CO2 when we burn fossil fuels such as coal or gas to warm a house, or power autos, or to generate electricity to play an Xbox.
Carbon is also released when trees are chopped down. A tree absorbs about forty-eight pounds of CO2 a year.1 When it is cut, or rots, or is burned, all the CO2 it has collected is released into the atmosphere.
Climate scientists are able to measure the weight of the carbon in the atmosphere over time. According to the National Oceanic and Atmospheric Administration (NOAA), the amount of CO2 concentration in the atmosphere has increased from the 1880 pre-industrial level of 280 parts per million (ppm) to 400 ppm in 2016.2 The last time the earth reached 400 ppm was during the Pliocene Epoch, between 1.8 million and 11,700 years ago, when the average temperature was two to three degrees Celsius warmer (almost four degrees Fahrenheit) than today.
Because of increased CO2 concentrations, the earth's current average temperature has risen about one degree Celsius since 1880.3 If no reduction in current emissions occurs, then the rise is on pace to increase six degrees Celsius by the end of this century.
HOW IS THE AVERAGE TEMPERATURE OF THE EARTH CALCULATED?
The French mathematician and physicist Joseph Fourier devised a way to calculate a planet's temperature. Because it was the 1820s, I will assume his planet of choice was Earth. He described it as the balance between energy received from the sun and how much was radiated back into space. In the 1850s, John Tyndall showed how atmospheric gasses help Earth to retain heat radiation.
According to the National Centers for Environmental Information (NCEI is a division of NOAA), as of January 2017, the average temperature of Earth was 12.88 degrees Celsius (55.18 degrees Fahrenheit). This is 0.88 degrees Celsius (1.58 degrees Fahrenheit) above the twentieth-century average for January.4
IS THERE EVIDENCE OF GLOBAL WARMING?
As always, look for evidence about any claim. In the case of global warming, the amount of evidence is vast. It includes rising sea levels, warmer oceans, a shrinking polar ice sheet, a declining artic sea, glacial retreat, and a decrease in snow cover. Going over all the evidence would be a book in of itself, so I'll elaborate on only a few.
CO2 is a very light molecule. Imagine you take your significant other for a romantic date floating over Paris in a hot air balloon. Because the heated air in the balloon is warmer than the surrounding air, the balloon expands as the warmest air pushes to the top. The rising action lifts the balloon into the romantic night (and the possibility of you creating descendants).
This is similar to what happens to the lower atmosphere as it collects carbon. The lower atmosphere, called the troposphere, has shifted upward in recent decades. (Please note that this shift might have nothing to do with you having descendants.)
In 2009, the Bramble Cay melomys (Melomys rubicola; think big mouse) became the first confirmed mammal killed off by climate change.5 They used to live on a low-lying island in Australia's Great Barrier Reef. The rising sea level destroyed 97 percent of the island's edible vegetation. No food, no melomys.
Since I brought up the Great Barrier Reef, let me tell you about reef loss. Today, about 75 percent of the world's reefs are at risk.6 Coral reefs are a community of corals; coral is a polyp, little organisms with tentacles that snare plankton and other small creatures. There is truth in the saying, it takes a village to make a reef. Coral reefs are the feeding grounds for 114 species of fish and fifty-one species of invertebrates.
Menu prices are skyrocketing due to the warming and acidification of oceans. Warm waters cause coral to lose the symbiotic algae that produces its food, a process called coral bleaching. Researchers are working on restoring exiting reefs with tiny coral transplants. Other scientists are experimenting with breeding stress-tolerant corals.7
IS ANYTHING BEING DONE TO PREVENT GLOBAL WARMING?
Policies to mitigate global warming can range from taxing companies for polluting to some pretty drastic geoengineering proposals that include blocking sunlight.8 Here is something to consider: who would control the policy on what the temperature should be? I don't know, but that would take some significant international cooperation.
The Paris Agreement, ratified in 2016, is an agreement to reduce carbon and to attempt to keep global warming from increasing another two degrees Celsius. This is good but not perfect. If the warming rises to this limit, plant and animal habitats will be destroyed, food crop yields will drop, and sea levels could rise.
If we want to get the job done (or at least slow it down), we need to do more than just lower emissions. We need to yank the existing carbon molecules out of the atmosphere. Enter carbon sequestration, the capturing and storage of CO2.
A lot of methods can accomplish this, but like everything, it comes at a price. Most of the methods use huge amounts of energy, which could make the problem worse. Engineers could design artificial trees that suck CO2 using chemicals that absorb and store carbon dioxide.9 Another idea is to add algae to building facades to absorb CO2.10
Don't forget oceans! We could fertilize them with large amounts of iron to bloom phytoplankton. Phytoplankton grows using sunlight and CO2. We would have carbon sequestered under the sea. There is no shortage of ideas. Making them work economically is the problem.
Researchers at Cornell University have an exciting (and entirely possible) solution. They've designed an electro-chemical cell that captures CO2 and generates rather than burns electricity.11 Think of it as carbon sequestration battery. If they can get it from design to reality in a cost-effective and scalable manner, these batteries could be attached to carbon emitters like car tailpipes or factory smokestacks.
In Iceland, researchers have discovered a way to sequester atmospheric CO2 by turning it into stone. They proved their concept by capturing emissions from a power plant and injecting it along with water into basalt rock. The gas formed into a very stable carbonate mineral with low risk of carbon leakage. A big hurdle of scaling this project is that it uses more water than the amount usually available to industrial sites.12
LET THERE BE (A LITTLE) LIGHT
One of the ways to prevent extinction from excessive climate change is to alter our physiology (transhumanism). This has already been covered in an earlier chapter, so let's jump to the alternative: modifying the planet. Geoengineering is all about changing the environment (rather than ourselves) to stave off the effects of global warming.
We could cool our planet by reducing the earth's absorption of sunlight. This can be done by emulating a volcanic eruption. It isn't as impossible as it might sound. If you have a pilot's license, you can join the fleet that conducts this operation. Squads of airplanes could fly into the upper atmosphere and spray sulfur. The permanent cloud would reflect sunlight.13 The color of the sky would probably change, and weather patterns might go wonky, but less heat would reach the earth's surface and the planet would remain habitable.
Another geoengineering possibility is to create glacier cozies. Tarp these big guys with
reflective covers to absorb heat and protect the ice below.14
Finally, how about a little sunblock? Space agencies could place trillions of satellite solar shields around the earth to reduce sunlight.15 For this venture, we might have to mine asteroids to pull together all the necessary resources. We would also need some really good guidance systems to prevent them from crashing into each other.
WHAT OTHER HUMAN ACTIVITIES AFFECT WEATHER?
Besides burning fossil fuels, humans have inadvertently manipulated the weather in other ways. In general, human land use has changed evaporation rates and altered albedo, the proportion of light and heat reflected by a surface.
Our increase in urbanization has caused “urban heat islands,” urban areas that are significantly warmer than surrounding rural areas. Cities tend to be warmer due to heat emissions from factories and cars. Buildings affect air flow, which redistributes precipitation in areas around cities. Metropolises cover land surface, lowering the albedo; also, when sunlight hits pavement, there is no evaporation and the sun's energy heats the ground.
Cities aren't the only places where humans affect the weather. Rural overgrazing and wind erosion results from poor agricultural planning. When trees (carbon absorbers and oxygen producers) are cut down to grow crops, surface albedo changes.
IS FICTION BEING USED TO HELP WARN ABOUT GLOBAL WARMING?
The Suck Zone. It's the point basically when the twister…sucks you up. That's not the technical term for it, obviously.
—Dustin (Dusty) Davis in the movie Twister
Yes, fiction helps spread the warning quicker, and to more people, than science journals. During the past decade, climate catastrophe has been used as a backdrop for science fiction and thriller novels. There is also eco-fiction, nature- or environment-oriented fiction like The Perfect Storm and Twister, that has its roots in science.
Sometimes fiction is threaded with a melodramatic urgency that belies solid science. Take the global warming disaster movie The Day After Tomorrow. In the movie, the Gulf Stream is shut down by global warming. This is not a real possibility, although mixed evidence does exist for its slowing. Also, the excessive rate at which the movie reports ocean rises from the melting of the Greenland ice sheet is exaggerated. The movie does succeed in spurring the general public to talk about the effects of global warming.
Tobias Buckell's novel Arctic Rising explores how the loss of ice in the Arctic Ocean might change international relations after the economic fortunes of nations are reversed.16 One thing I'd bet on to not be fiction: if the environment keeps changing, we will end up with climate refugees. People would move to cooler areas that most likely are already occupied. In the novel The Water Knife by Paolo Bacigalupi, the water-depleted American Southwest is carved into small warring nation-states fighting over the remnants of the Colorado River.17
Let us not forget the aliens. Wesley Chu's The Lives of Tao is about aliens who want to settle on our planet. They deliberately harness humans to change the earth's climate by causing runaway greenhouse gasses.18
The Hugo Award–winning The Three-Body Problem by Cixin Liu artfully uses the backdrop of climate change to emphasize a political drama. Humans have failed the earth, so a sympathetic main character helps aliens take over because it is (possibly) what we deserve.19 Michel Farber's The Book of Strange New Things: A Novel turns this idea on its head; humans fleeing a dying Earth cause human-style environmental havoc on an inhabited alien world.20
PARTING COMMENTS
Humans have inadvertently changed the atmosphere over the past century. The net result is global warming. This is an existential threat, but because it is happening so slowly, we don't feel any urgency to respond. This is a not-insignificant side effect of the survival instinct. The instinct, which has served us well, is to consume today rather than save for tomorrow. Therefore, many humans don't worry about the environment as much as they should.
Can we kick the fossil fuel habit? Swap it out for the low-emission cast of characters known as wind, solar, and nuclear power? Yes, we can, and we will. The only issue is the speed with which we act.
To give us the time we need to develop genetic and technological modifications (or habit modifications, or moving our rears ends out of town and to the stars), we can aggressively enact policies to reduce CO2 concentrations. We might also use geoengineering technology to slow the warming before the sea levels rise too much and gift us with floods, or before the oceans grow too acidic and tamper with our food supply. Let's just say that if you think parts of Africa are dry now, imagine them after droughts and extreme heat.
CHAPTER 11 BONUS MATERIALS
BONUS 1: NEGATIVE GREENHOUSE EFFECT
Rising CO2 levels can sometimes lead to global cooling. Evidence of this is found in central Antarctica.21 Rather than radiating heat from the ground, CO2 increases the amount of heat that escapes into space. The amount expelled is usually offset by heat trapped in the ground. In Antarctica, the ground is so cold little heat is radiated.
This does not contradict the rise in the average global temperature. The increase in temperatures throughout the rest of the world overwhelms this small local increase.
BONUS 2: A DAWNING OF A NEW AGE (REALLY, AN EPOCH)
The geologic timeline is divided into major divisions of geological time called eons. Eons are made up of eras, and eras are made up of periods, and periods are made up of epochs. We are currently in the Phanerozoic eon, Cenozoic era, Quaternary period, Holocene epoch.
Geological epochs are transitions that result in permanent change. The Holocene epoch began about twelve thousand years ago when the Ice Age receded and civilization arose. Good for us! This is our current epoch.
Or is it? A lot of scientists are calling for the announcement of a new epoch called the Anthropocene, the beginning of an exciting and scary time for us Earth dwellers. It is a period during which, for the first time in the planet's history, self-aware—meaning human-influenced—geologic forces can shape the planet. Steel, plastic, and concrete are this proposed epoch's techno-fossils.
BONUS 3: THE OZONE LAYER
Ozone is created from chemical reactions of the O3 molecule in the upper atmosphere (stratosphere) as it graciously absorbs 97 percent to 99 percent of the sun's UV rays. Trust me, these are not the rays you want for your suntan. The DNA damage can lead to skin cancer. For every two million oxygen (O2) molecules, only three O3 molecules exist. When a UV ray hits an O3 molecule, the ray splits it into an unstable O2 that binds to another O1.
If you want to mess with the chemistry of the ozone, send up some chlorofluorocarbons (CFCs). These release binding chlorine. A single chlorine atom can destroy up to 100,000 O3 molecules.22
Not all of the environmental news is bad. The Montreal Protocol, which was adopted in 1987, was intended to phase out CFC use by 2010.23 The initiative appears to have been a success. The ozone layer is on the mend after many years of bombardment with CFCs from refrigeration and spray-can propellants.
NASA are idiots. They want to send canned primates to Mars!
—Charles Stross, Accelerando
The universe offers many more ways to die than to survive. Surprise! Possibly the only place in the entire universe for us humans is right here on good old terra firma. Even on our home planet, we can't survive just anywhere. A lot of the land is frozen tundra or arid desert—and don't forget that most of the area is covered by oceans.
I wouldn't want to see the scary ending of the “all eggs in one basket” scenario. What if an asteroid struck the earth, or global climate changes caused human extinction (unless we embrace transhumanism), or, if you want to go all science fiction, alien invasion? So, if not solely for the pure joy of exploration, some of us should probably hightail it off the earth and start filling other baskets.
To me, the most interesting alternative to being cramped inside enclosed space station habitats or hollowed-out asteroids is to colonize another planet. Only, as with most things in survival science, this idea
isn't quite that simple to realize. What are the odds of landing on some planet that offers the bare necessities and biodiversity essential for human life? Probably less than getting two royal flushes in a row.
I've heard that, on rare occasions, cheating arises in poker. An unscrupulous dealer might manipulate the cards to help one player. Since it is unlikely for humans to move to a ready-made planet, scientists have been thinking up ways of doing a bit of cheating to improve the odds. They have thought up ways to rig our bodies through genetic modification or to rig the planet's environment. This chapter focuses more on the planetary science, but I'm sure genetic manipulation will pop in from time to time. Colonization will probably require a blend of both.
The climate science of the last chapter is important not only for understanding the earth but for understanding how to adjust the environments of other planets. As a science Zen master might say, “Before we can change another world, we must understand our own.” This outward-looking planetary science is called terraforming, the science of making other planets (or asteroids) more hospitable to Earth life.
Terraforming is all about tweaking what a planet already has. The amount of tweaking depends on how different the biosphere of the target planet is from Earth's and/or on how much we have modified our bodies. In the end, terraforming might be our escape hatch if something disastrous happens to our planet.
Fig. 12.1. Illustration of terraforming.
Terraforming was first mentioned not in a scientific journal but…in science fiction. The word was first used in the short story “Collision Orbit” by Jack Williamson in 1942.1 It took a while for mainstream science to get the jargon right. Does the original scientific term ecosynthesis sound as exciting? I thought not.
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