Climate was generally very dry over much of Pangaea with very hot summers and cold winters in the continental interior. A highly seasonal monsoon climate prevailed nearer to the coastal regions. Although the climate was more moderate farther from the equator, it was generally warmer than today with no polar ice caps. Late in the Triassic, seafloor spreading in the Tethys Sea led to rifting between the northern and southern portions of Pangaea, which began the separation of Pangaea into two continents, Laurasia and Gondwana, which would be completed in the Jurassic Period.
The oceans had been massively depopulated by the Permian Extinction when as many as 95 percent of extant marine genera were wiped out by high carbon dioxide levels. Fossil fish from the Triassic Period are very uniform, which indicates that few families survived the extinction.
Surface temperatures were roughly 3 degrees C higher than preindustrial modern times, ie the worst case scenario the IPCC is suggesting, and mean atmospheric CO2 content was roughly 1750 ppm, or six times higher than preindustrial levels.
Jura:
Climates were warm, with no evidence of a glacier having appeared. As in the Triassic, there was apparently no land over either pole, and no extensive ice caps existed.
Here too surface temperatures were roughly 3 degrees C higher than preindustrial modern times, and mean atmospheric CO2 content was roughly 1950 ppm, nearly seven times higher than preindustrial levels.
As I've said before, the CO2-levels, temperatures and sea levels won't be a problem for earth itself, merely for the present day life forms, that are adapted to a cooler climate.
The CO2 levels now are higher than ever before in the history of mankind, and temperatures are rising. That could be a problem for us.
Compared to the CO2 levels and temperatures of ancient times, they are still ridiculously low, but our species has never experienced that kind of climate, so we don't know how well we can cope with it.
Re: It's getting warm
Posted: Mon Sep 30, 2019 8:56 am
by Topper
That +/- 200ma time is extremely important on BC geology, all our major porphyry Cu-Au deposits formed around that time and are within kilometres of of the mapped exposure of the nonconformity that occurred around that time. I do quite a bit of work in that time window.
You are leaping around a fair bit in times in your post. Several 100's of millions of years. That brings into stark contrast what people are trying to extrapolate from 200 years or less of data. We have no idea of the variations within smaller time frames in geological history but I don't think there is any doubt there were variations
Two divisions in evolutionary science, jerks and creeps. Jerks believe these mass extinction events along with lessor events open space for vast genetic variations to follow and signify giant leaps in evolution because competition was limited. Creeps discount that and prefer a steady stream of genetic variations through time. The big thing to remember when talking of evolution is that it is a random process of mutation. Some mutations give the individual a competitive advantage, others are hindrance.
Re: It's getting warm
Posted: Mon Sep 30, 2019 12:14 pm
by Per
Topper wrote: ↑Mon Sep 30, 2019 8:56 am
The big thing to remember when talking of evolution is that it is a random process of mutation. Some mutations give the individual a competitive advantage, others are hindrance.
Exactly, it is not a guided process (as in breeding), it is random. And what is an advantage in one setting could be a disadvantage in another. Some species got it right a long time ago. Sharks, crocs and turtles all predate dinosaurs and still hang in there. But they have never ruled the world. Most really successful species are dependent on the conditions they thrive in, and once those conditions change, they are doomed.
Animals like pandas and koalas basically only eat one thing, but it’s a thing they have very little competition for. As long as that one thing they eat is plentiful they thrive. If bamboo and eucalyptus disappear, so do they.
Rats and humans have an advantage in that they can eat almost anything, both plants and meats, and are smart enough to adapt to different climates. This speaks for us being able to ride out whatever perils the climate change brings. But it probably won’t be a walk in the park.
Re: It's getting warm
Posted: Mon Sep 30, 2019 12:26 pm
by Per
Topper wrote: ↑Mon Sep 30, 2019 8:56 am
You are leaping around a fair bit in times in your post. Several 100's of millions of years. That brings into stark contrast what people are trying to extrapolate from 200 years or less of data. We have no idea of the variations within smaller time frames in geological history but I don't think there is any doubt there were variations.
Sure. The temperatures and CO2 concentrations are averages. There was certainly variations, like the rise in CO2 that killed off almost all aquatic life.
But the point was that I agreed with your statement that CO2 levels having been times higher than today, and that temperatures then (on average) were in the range we consider unsustainable.
But it was fine for the dinos. They thrived.
And then the climate changed and they didn’t.
Except for the tiny feathered dinosaurs that could fly,
They are still around, but we now call them birds.
Re: It's getting warm
Posted: Wed Oct 02, 2019 8:31 am
by Per
Re: It's getting warm
Posted: Fri Oct 04, 2019 4:52 pm
by Strangelove
.
^ yup, she definitely looks like the antichrist Per
Speaking of that, is this the next Greta Thunberg:
Re: It's getting warm
Posted: Fri Oct 04, 2019 7:11 pm
by 2Fingers
Strangelove wrote: ↑Fri Oct 04, 2019 4:52 pm.
^ yup, she definitely looks like the antichrist Per
Speaking of that, is this the next Greta Thunberg:
Climate fearmongers are burning their Bob Marley records.
Rastfari
Re: It's getting warm
Posted: Fri Oct 11, 2019 3:28 pm
by 2Fingers
Hey Top - what do you think about the rising water levels and the talk about how certain cities that are on the ocean fronts will be under water in future years? If these cities were built hundreds or thousand years ago do you not believe that if they are flooded that it means the climate changed?
Reading some of your posts and the job I assume you do, you have some experience in this area?
This is not a negative question or questioning your thoughts/comments, just want to hear your opinion.
and feel good about it 
