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Early Plants May Have Caused Massive Glaciation
sciencehabit writes with this excerpt from Science: "The first plants to colonize land didn't merely supply a dash of green to a drab landscape. They dramatically accelerated the natural breakdown of exposed rocks, according to a new study, drawing so much planet-warming carbon dioxide (CO2) from the atmosphere that they sent Earth's climate spiraling into a major ice age."
A large-scale version of that is sometimes proposed...
10 PRINT CHR$(205.5+RND(1)); : GOTO 10
Indeed, and it makes me want to slap the shit out of everybody who starts talking about 'carbon footprint'. Carbon is life itself.
Everybody worried about global temperature should really take a look at temperature over geologic timescales. Two centuries ago it was colder than any other time in the last two millennia. That last two millennia have been colder than most of the last ten or so since the last glacial period. Glacial periods notwithstanding, the last few million years have been the coldest in the last hundred million years. Modern, industrialized mankind was essentially born during the coldest period outside of an actual glacial cycle. Modern meteorology/climatoloy started at the bottom of a very cold well, and now that we're starting to get to temperatures that used to be normal, we're freaking out just because we haven't had to deal with it before in a conscious way. E.g. last time it was this warm we were still performing human sacrifices to appease imaginary agents of dubious intent. This whole society needs a clue-by-four to snap them out of the delusion that warming is the end of the world and any more a threat to life than all the other environmental changes that have already killed 99% of all species that have ever existed.
I support the Slashcott and will not be reading or commenting from 2/10/14 to 2/17/14. Beta is steaming pile of dog shit
Way to cherry pick. In the very same paragraph "At the time, the sun was as much as 6% fainter than it is now, Lenton says, so the planet-warming effect of greenhouse gases wasn't as strong."
(1) Biosphere: (medium) abundance of plants and peat deposits, waxing and waning with ice ages. Changes over 10,000s years.
(2) Plate tectonics: (long) carbon capture in limestone, release from subduction volcanoes, possible permanent burial in subduction. Plates change speed, length of subduction zones over 100,000s to millions of years. Limestone contains 100 times the carbon in the biosphere and draining out the atmosphere over 100s of millions of years.
(3) Human: (short) deforestation, extraction and combustion of hydrocarbons. Just centuries. Deforestation will reach steady state soon like in North America and Europe. We are probably midway through 300-400 year "hydrocarbon age" of consuming all the extractable petroleum, natural gas and coal.
Why do the ice cores reveal co2 concentrations at the height of the last ice age at 20 times today's readings?
Where did that come from? Got a reference? From what I know CO2 concentrations were around 190 ppm at the height of the glaciations and today they're around 390 ppm, over twice as high.