• Tectonics in the tropics trigger Earth’s ice ages, study finds
    15 replies, posted
http://news.mit.edu/2019/tectonics-tropics-trigger-ice-ages-0314 In a study published today in Science, the team reports that each of the last three major ice ages were preceded by tropical “arc-continent collisions” — tectonic pileups that occurred near the Earth’s equator, in which oceanic plates rode up over continental plates, exposing tens of thousands of kilometers of oceanic rock to a tropical environment. The scientists say that the heat and humidity of the tropics likely triggered a chemical reaction between the rocks and the atmosphere. Specifically, the rocks’ calcium and magnesium reacted with atmospheric carbon dioxide, pulling the gas out of the atmosphere and permanently sequestering it in the form of carbonates such as limestone. Some of those please
Do it again please fucking end us
That's actually really fucking amazing.
What a curiously unexpected chain of events.
Ha! Humans didn't do anything wrong and this was all just part of the natural cycle. Way to go libtards! /s
why don't we just shoot rockets at it to cause it and compensate for global warming?
Funfact: Humans probably have inadvertently created earthquakes. In the '60s the US Army decided it was a good idea to dump 165 million gallons of waste from various sources (including napalm production) in a 12000ft well in the Rocky Mountains. A bunch of earthquakes followed which were attributed to it. Manipulating tectonic plates would be something on a rather grander scale, though.
I feel like if we do that it would probably be just a temporary excuse not to do anything for the environment again
sometimes it's easy to forget that the earth is just a really big rock and not exempt from the laws of physics
I think the idea is that the earth is a big ball of rocks, some rocks (tectonic plates) bigger than others
Not to mention hydraulic fracking which is literally designed to destabilize rock beds to release natural gas, in some areas inadvertently disturbing ancient fault lines and creating earthquakes 3.0+ in areas that had no activity before fracking began Or how about the time that the US detonated a 5MT nuclear warhead underground just to see what would happen, which also sparked the creation of Greenpeace
yo, lets do that. Its worth it if it can slow/stop climate change
Tectonics in the Tropics would be a good band name.
[...] some scientists have proposed grinding up vast quantities of ophiolites and spreading the minerals throughout the equatorial belt, in an effort to speed up this natural cooling process. But Jagoutz says the act of grinding up and transporting these materials could produce additional, unintended carbon emissions. And it’s unclear whether such measures could make any significant impact within our lifetimes. “It’s a challenge to make this process work on human timescales,” Jagoutz says. “The Earth does this in a slow, geological process that has nothing to do with what we do to the Earth today. And it will neither harm us, nor save us.” It looks like adaptation is the only option we will ever have. Carbon capture, especially using something as natural as this, simply cannot meet or exceed the amount of carbon in the atmosphere. This, combined with melting permafrost releasing methane, probably means that there is no way to stop it. If anything, we might accidentally cause an ice age a few thousand years in the future if we really committed to spreading carbon-eating rocks everywhere while also eliminating all future emissions. That doesn't help the here and now, though. It just fucks up the future even further.
Wait aren't ice ages triggered by peturbations in the earth's orbit?
Overall? No. Technically? Depends on scope and what you define as an ice age. There are three common definitions: A glacial maximum, which some people interpret as the ages, themselves. Casually, this is usually interpreted as not being in an ice age, though we still are. The formation of both ice caps. This is an extremely rare thing in the history of the Earth, and only has likely occurred thrice: Twice when the Earth nearly entirely froze over in the Huronian (which nearly wiped out life) and Cryogenian (which the end of precipitated the evolution of the Edicarian biota that eventually became the Cambrian explosion, and formed the most extensive amount of ice the Earth has ever seen. Some speculate that the equator may have even had permafrost that was only destroyed by volcanic activity, which would have made Earth look like Europa at the time), and the one we're in now The formation of one ice cap. In this case, Antarctica's started forming because the Arctic Ocean became full of ferns called Azola as a coat of freshwater existed in the Arctic because seawater was not able to flow, meaning rainwater that fell did not mix. This event, called the Azolla Event, resulted in worldwide CO2 loss because these freshwater plants sink when they die, sending the C02 to the bottom of the sea. The biome of the Arctic at the time would have been fairly unique, as that was the only time known so far that an ocean had a freshwater layer that would result in distinct life above and below it and reptiles like alligators would have been found throughout the Arctic. For argument sake, the current ice age usually refers to the formation of two ice caps as it is more relevant to today. Glacial maximums and glacial minimums are affected by peturbations in the Earth's orbit over what are called Milankovitch cycles. These are what you are thinking of. The ice age as we know it though is known to be due to oceanic currents due to a twofold issue: in order for the poles to stay warm, warm water needs to be able to travel toward them, and gyres, circular currents caused by the Earth's rotation, are the means for these to get there. As Australia and South America separated from Antarctica, water circumnavigating Antarctica would be forced upward on the east coasts of these continents, but their current configuration is enough for the Antarctic circumpolar current to pass through, meaning cold water does not get forced northward from the south pole in order to get warmed. However, there's another aspect that's even more crucial and tantamount to the environment we have today: the formation of the Isthmus of Panama. You may ask "How does an equatorial extension of land affect currents at the pole?" and if you just looked at a map of gyres painting the surface currents, you'd be understandable for not getting this. However, our oceans are three-dimensions, not two! Here's a depiction of the 3D movement, which is typically coined the Great or Global Ocean Conveyor Belt: https://pubs.usgs.gov/pp/p1386a/images/gallery-2/full-res/pp1386a2-fig31.jpg Before the Isthmus of Panama formed, deep sea water would have been forced through from the Pacific into the Atlantic mildly, and northeastward around it and if it remained cold, have flowed down the east side of SA back southward, but importantly, look at the path of the warm shallow current. See how in the northern Atlantic the current reaches a dead end, and is forced to sink into cold water? Panama is responsible for this, as it would have otherwise flowed south of Hispanola and into the Pacific, resulting in a global warm shallow current that stayed warm! Effectively, there's a feedback loop where seawater is constantly forced into areas that receive far less radiation in addition to exposure to colder climates, and this helps cool the Earth. In addition, Australia is crashing into Asia, which is how the Indonesian Archipelago is forming, and will also inhibit the warm shallow current from passing through there, eventually, further isolating the movement of water in the Pacific with time. If you want to go even further back in time, Africa was once an island continent which had it's own unique mammals that, aside from elephants, elephant shrews and a few others like hyraxes, have been mostly displaced by Eurasian fauna. At that point in time, the oceanic current went through what is now the Mediterranean and Red Seas, which was classified as the Tethys Sea. Basically, the combination of South America and Australia moving north and the collision of the two Americas helped to create two stages to the cooling that originally started because of both Africa moving north and the Arctic being choked into isolation by the North America and Eurasia temporarily being connected as a nearly complete ring at the time.
Sorry, you need to Log In to post a reply to this thread.