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Mathematical Formula Predicts Global Mass Extinction Event in 2100 (vice.com)
Kate Lunau, writing for Motherboard: A new paper in Science Advances finds that a mass extinction period mirroring ones from our planet's ancient past could be triggered when humanity adds a certain amount of carbon to the oceans, which are home to the majority of all plants and animals on our planet. The paper pegs that amount at 310 gigatons. According to lead author Daniel Rothman of MIT, based on projections from the Intergovernmental Panel on Climate Change, we're on course to hit that number by 2100. After that, we enter "unknown territory." [...] Previous mass extinctions have happened over the course of thousands or millions of years, but the period of change we're in right now has lasted centuries at best, making it hard to compare them. Although plenty of experts say Earth is already experiencing a sixth mass extinction, that remains "a scientific question," Rothman, who is professor of geophysics in the MIT Department of Earth, Atmospheric and Planetary Sciences, told me. Once our planet hits the threshold he identified in this paper, he explained, it will kickstart changes that will "amplify" everything that came before. These same changes, to reiterate, have been associated with all previous mass extinctions on Earth.
The possibility of a catastrophic feedback is indeed the wild card in global warming calculations: there is a lot of carbon dioxide and methane trapped in frozen soil and in undersea clathrates, and it is indeed possible that there is a threshold above which these will be released, dramatically increasing the temperature.
It's not a "wild card," it is considered so unlikely by scientists that after consideration, the IPCC didn't even put it in their report as a reasonable possibility. Nature has a good summary of the research:
Catastrophic, widespread dissociation of methane gas hydrates will not be triggered by continued climate warming at contemporary rates (0.2C per decade; IPCC 2007) over timescales of a few hundred years. Most of Earth's gas hydrates occur at low saturations and in sediments at such great depths below the seafloor or onshore permafrost that they will barely be affected by warming over even 10^3 yr.
"First they came for the slanderers and i said nothing."
I cannot believe how freaked out everyone is about carbon, when it is a basic and abundant element of the planet...
People are "freaked out" about carbon-- specifically, carbon dioxide in the atmosphere-- because it is known to absorb outgoing infrared radiation, so the amount of carbon dioxide in the atmosphere affects the temperature balance of the planet. This is an effect that has been known for a very long time (here's a good review from the American Institute of Physics: https://history.aip.org/climate/co2.htm), but only recently has the amount of carbon dioxide put in the atmosphere by humans been enough to make the effect visible.
You're correct that it is "basic and abundant", although I'm not sure why that's relevant
the amount in the atmosphere is minuscule to begin with,
Correct. It was the great discovery of Tyndall in 1859 that extremely small amounts of trace gasses can affect the infrared absorption. https://earthobservatory.nasa....
never mind whatever we are adding in being a tiny fraction of what it is already.
Humans have increased the carbon dioxide content of the atmosphere by about 45% since preindustrial times, most of that in the last century (graph: https://www.esrl.noaa.gov/gmd/...). Depends on whether you call that a "tiny fraction."
But, indeed, the natural greenhouse effect of about 30C (ref) is about much larger than the human contribution. That's one reason we understand the greenhouse effect; it's large enough to be easily measured.
The entire ecosystem of the Earth is built to process carbon, to consume carbon, to use carbon to sustain life.
Correct again. Over a period of few hundred thousand years, this will undoubtably be removed from the biosphere.
It would be lot faster than that, except we're cutting down trees a lot faster than we're growing trees.
It is so sad to see rational people get lost in a death cult that makes absolutely no sense to anyone with a shred of scientific understanding of the climate, or indeed basic material science...
I will assure you that I have a pretty good scientific understanding of climate, and also of basic materials science. This is how we understand the atmospheres of all the planets, not just Earth. The basic physics of the greenhouse effect is quite well understood science, and the absorption coefficients of trace gasses in the infrared are all well measured.
http://www.geoffreylandis.com
As usual, someone misinterprets data for their own personal agenda. When the ratios of C02 and/or light are changed, plants food production changes. Increasing light or C02 makes plants create more sugar and less vitamins , proteins and important nutrients. Plants are becoming less and less nutritious as the C02 level raises.
http://grist.org/briefly/veggi...
Do your own searches, lame ones.
OK, I did. Shockingly, you're completely full of shit.
Climate change and rising CO2 are altering the behavior of land plants in ways that influence how much biomass they produce relative to how much water they need for growth. This study shows that it is possible to detect changes occurring in plants using long-term measurements of the isotopic composition of atmospheric CO2. These measurements imply that plants have globally increased their water use efficiency at the leaf level in proportion to the rise in atmospheric CO2 over the past few decades. While the full implications remain to be explored, the results help to quantify the extent to which the biosphere has become less constrained by water stress globally.
http://sci-hub.io/10.1073/pnas...
"Starting in 2018 more than 80 percent of all cars and trucks sold worldwide will be electric only or plug-in electric hybrids with a biodiesel option."
80 percent, you say.
"Despite their rapid growth, plug-in electric cars represented only 0.15% of the 1.4 billion motor vehicles on the world's roads, up from 0.1% in 2015." - Wikipedia - https://en.wikipedia.org/wiki/...
Hmm.
You are in a twisty maze of processor lines, all alike.
There is a lot of hype here.