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In the meantime, something a bit more theoretical. Or not.
"...the dumbest experiment in history, by far." -- Elon Musk
Elon Musk is not talking about my Kill-A-Watt project. He's talking about extracting fossil fuels that have been buried for millions of years and burning them in the space of a few hundred years.
The following elaborates on Elon's sentiment.
According to the fossil record, anatomically-modern humans have been around for about 200,000 years. They've had some times when the climate was sort of like ours, and other times when it was a lot colder. They, no doubt, were well aware of the temperature, especially when it was cold -- or in the case of the Mayans, for example -- when it got really hot and dry.
What was less obvious to anatomically-modern humans over this 200,000 years was that the carbon dioxide (CO2) level in the atmosphere went up and down. Specifically, CO2 ranged from about 180 parts per million (ppm) up to 300 ppm, but no higher. NASA produced this really nice graph to show what CO2 has been doing over the past 400,000 years (note that anatomically-modern humans have been around only for 200,000):
Atmospheric carbon dioxide levels over the past 400,000 years. Source: http://climate.nasa.gov/climate_resources/24/.
NASA got this data from scientists measuring CO2 in air bubbles frozen into Antarctic ice in Vostok, Antarctica.
A scientist measuring CO2 in a Vostok, Antarctica ice core sample.
Source: http://scientificamerican.com
What's carbon dioxide got to do with anything? Check out this graph. The green graph is CO2 variation over time (the same graph as the NASA one above), while the blue graph is temperature variation.
Notice anything?
"Vostok Petit data" by Vostok-ice-core-petit.png: NOAA derivative work: Autopilot (talk)
Vostok-ice-core-petit.png. Licensed under CC BY-SA 3.0 via Commons https://en.wikipedia.org/wiki/Ice_core#/media/File:Vostok_Petit_data.svg
(1) Is this a coincidence?
(2) If not, does a warmer climate mean more CO2 in the atmosphere?
(3) Or if not, does more CO2 in the atmosphere mean warmer climate?
Both #2 and #3 seem to be true. The story appears to be pretty complicated, involving something called Milankovitch cycles. An explanation of these cycles and how they affect temperature and CO2 levels is more complicated than I really want to go into in this blog post. Suffice it to say that the Milankovitch cycles appear to get warming started, which releases CO2 from the oceans. The increased level of CO2 kicks in the well-known greenhouse effect that pushes up the temperature (https://en.wikipedia.org/wiki/Greenhouse_effect). For various reasons, temperature eventually peaks and starts to fall, causing CO2 to be absorbed back into the oceans. As the CO2 level falls, less solar energy is trapped, and temperature falls. Temperature and CO2 decline into a valley, at which point the Milankovitch cycle comes by and kicks off another round of warming.
Note that there is still no conclusive explanation for glacial cycles, with a lot of scientists still working on the question. If you want to know more about the current state of research on the matter, Google "explain glacial cycles".
The valleys on the CO2 and temperature graphs are called "glacial periods" and the peaks have the highly-imaginative name of "interglacial period".
Over the 200,000 years anatomically-correct humans have been around, there have been some glacial periods, like the one that ended about 10,000 years ago. This glacial period actually lasted from 110,000 years ago to 12,000 years ago (https://en.wikipedia.org/wiki/Last_glacial_period). That must have been a long 100,000 years.
Take a moment and look at our temperature and CO2 graphs -- exactly during this 100,000 years, the Vostok ice cores say that temperature just kept getting colder and colder. The Vostok data seems to be consistent with geologic data.
Also note that when we anatomically-modern humans first showed up, temperature was on a decline. This kind of sucked -- just when we show up, times start to get more and more difficult. There were the lucky ducks at around 125,000 years ago who had nice weather, but for a lot of the rest of the 200,000 years, it's been rather wintery, at least in the high latitudes.
Also note that WE -- present-day anatomically-correct humans -- are riding a peak! That means we're among the lucky ducks to have a nice, warm climate (tell that the Vostok scientists whose teeth are chattering, eh?).
But we anatomically-correct humans couldn't leave well enough alone...
Go back to the NASA graph (the first one). Notice what's going on in the graph at the very right. Here's the graph again so you don't need to scroll:
Atmospheric carbon dioxide levels over the past 400,000 years.
Notice the sudden rise in CO2 at the very right.
Something funny happened starting around 1950. CO2 (which hadn't been above 300 ppm for 600,000 years) suddenly goes straight up from 300 ppm to 400 ppm. Is this nature just messing with us?
Most likely not. It might have something to do with this:
World Energy Consumption in Terpinkajillanjoules per year by anatomically-correct humans.
Source: http://ourfiniteworld.com/2012/03/12/world-energy-consumption-since-1820-in-charts/
Notice something funny? Once again, even the most frozen Vostok ice scientist would point out that the colored part of the World Energy Consumption graph above starts to get real fat and streak upward at about 1950. Hmmm...
Let's see. CO2 started going up dramatically around 1950. We started burning lots of fossil fuel around 1950. Burning fossil fuel produces lots of CO2 (one gallon of gas -- which weighs about 6 lbs -- produces about 19 lbs of CO2 when burned; think of that each time you drive). Rising CO2 increases temperature. Uh oh...
Well, the temperature hasn't gone up (at least that much), which is why Elon Musk calls it an "experiment". Still, there's already enough data showing that temperature is rising, and I wouldn't bet against Elon.
Temperature change over the last 135 years. To see an entertaining animated GIF version, click on
So, what's the problem? Warm is good, no? Don't we like nice summery weather?
Actually, there are several problems. Some of them are:
(1) The climate gets hotter and drier. Ask the Mayans (or for that matter Californians) about this.
(2) Higher temperature means more energy in the atmosphere means more vigorous weather. This means that storms like Superstorm Sandy and Mega-Blizzards are more likely. Kind of counter-intuitive that higher temperatures would mean more snow. Maybe Jim "Snowball" Inhofe can explain.
(3) Higher temperature means melting ice and expanded ocean water, both leading to rising sea levels. Eventually we could end up with a coast line that looks like this:
US shoreline resulting from rising ocean levels.
Source: http://ngm.nationalgeographic.com/2013/09/rising-seas/if-ice-melted-map
Florida is completely underwater, as is Long Island, Cape Cod, Boston, most of New York City, much of New Jersey. Then there's the whole Gulf of Mexico coast. Forget New Orleans -- no levee will hold back the water at this point. And California looks kind of funny also, with its waterfront properties in the Sierras.
Some people would say "good riddance" until they realize that the people who lived in the now-underwater places would like to share your space, food, water. Could get ugly. Ask the Mayans.
So, to wrap this up, what to do? Maybe it's already too late. We've put the CO2 into the atmosphere, we can't get it out, and temperature is going to rise no matter what. Hopefully that's the worst case.
Others are more optimistic. They point out that trees and oceans could become our best friends, rapidly photosynthesizing and absorbing the excess CO2 out of the air, while we anatomically-correct humans get our act together and stop putting more excessive CO2 into the air.
I'm more or less with the optimists, but the realist part of me knows that limiting CO2 release to a sustainable level is much easier said than done because there's a lot of easy money in putting CO2 into the air. This makes me suspect that we will end up burning pretty much all the fossil fuel we can find, while hoping and believing that all the extra CO2 won't increase temperature that much.
If we're wrong, then in a century or so, the ghost of Elon Musk may be back to say, "I told you so."
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