Livedeadcat
Forum Replies Created
-
Posts
-
In about one year’s time, the CO2 content in the earth’s atmosphere has gone from a first reading of 400 ppm to consistently reading over 400 ppm. When Keeling developed the first accurate method of measuring CO2 back in the 1950’s, the first thing he noticed was that his measurements varied day-to-night (attributed to lower photosynthesis in darkness) and summer-to-winter (attributable to seasonal changes in the ratio of hours of daylight to darkness). That is why the “Keeling Curve” has a saw-toothed pattern over time. The next thing Keeling observed was the inexorable upward trend in the amount of CO2, year-over-year. This trend had been suspected since the turn of the twentieth century, and Keeling’s measurements merely proved it. Even before the trend was accurately measured, the principle source of the extra CO2 had been clearly identified as combustion of fossil fuels.
Carbon dioxide may seem to to some to be “clear and colorless” (a distinction without a difference and perhaps a misstatement of “colorless and odorless”), but it is actually photochemically active, absorbing photons and then reradiating them in all directions. One result of this property is that CO2 in the atmosphere redirects some of the light reflected from the surface of the earth back toward earth, where its energy excites molecules to produce what we call “heat.”
The atmosphere has always contained “greenhouse gasses,” like the small amounts of CO2 and much larger amounts of water vapor. These gasses can be thought of as a blanket that retains the warmth of the sun. Without them, earth would be as cold as its moon. The problem for us (and for all of life on earth) is that CO2 formerly sequestered over millennia in fossil form is now being reintroduced into the atmosphere at a rapid rate, perturbing the ratio of insolation to reflection, which in turn perturbs weather (a large part of which is the interaction between relatively warmer areas and cooler areas). Weather over time is what we call “climate,” and systemically increasing greenhouse gasses fundamentally changes the weather. We call that climate change.
It gets worse: For instance, it is true that CO2 is absorbed by the oceans. It is also true that, as the oceans warm up, they lose their ability to retain absorbed CO2, which is then released back into the atmosphere, further warming it (and the oceans as well). This is positive feedback, like holding a microphone in front of a loudspeaker. And then there are the clathrates. Don’t get me started on that….
Ironically, the relatively stable climate of the holocene is what permitted humans to develop agriculture and then “civilization,” which seems to be responsible for climate destabilization.
The sad truth of our circumstance may well be summed up in my epitaph for mankind, “We played with fire.”
I should not drink coffee after noon.
Here in Northern California, Dr. Jeffrey Abel, chair of the Oceanography Department at Humboldt State University, reported a reading of 400 ppm CO2 in April of 2013, taken at the department weather station at Trinidad Head, known for the clearest air on the west coast.
Kunstler has long been my favorite crank. I try not to miss his Monday morning missives (kunstler.com), where I always appreciate his linguistic legerdemain and often learn a new word or two in the bargain. Like most Doomers, I keep waiting for the other shoe to drop, and while I’m waiting for that slow freight train to arrive, Jim helps me laugh.
There is another kind of tipping point, which engineers call “phase change.”
In this situation, the load can be increased far beyond the point of equilibrium before it reaches a toggle point. An example of this might be the Greenland ice sheet, which can decay pretty far without substantial movement. Then, suddenly and without warning, the whole thing goes, something everyone thought should have happened much earlier. Or, using the straw-loading example, the calculated toggle point might be far exceeded before the camel’s knees actually give out.A sense of complacency might be a likely result when expected overloads do not result in collapse.
