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Chicxulub for the win!

Unread postPosted: Wed 20 Jun 2018, 11:43:32
by KaiserJeep
Image
According to a recent article at space.com, the 65-million-year-old impact of the Chicxulub meteor/comet/asteroid/whatever caused Climate Change impacts that subjected Earth to approximately 100,000 years of elevated temperatures, averaging 5 degrees C above global averages. The "triple whammy" went something like this:

1) At the time of impact, the mechanical impact of the collision released enormous amounts of energy, and ignited fires that swept all continents surrounding the Atlantic, save possibly the remote tundra of Eastern Asia and the continent of Australia, which caused even more warming due to combustion of more than half of the plant biomass at the time. This temperature increase lasted for hours to days.

2) The huge amounts of dust and smoke released into the atmosphere circled the globe, blocking sunlight and causing global temperatures to plummet for a period lasting months to decades, in a grim preview of what might result if we ever experience "Nuclear Winter".

3) The huge amounts of carbon dioxide released then caused a period of Global Warming, and the new information is that recovery from this planetary scale warming period took over 100,000 years.

The implication being: If human activity is increasing global temperatures, the outside bound for the healing period when FF combustion ends may be on the order of 100,000 years.

The climate information came from the rather complete record of fish remains (teeth, scales, and bones) found in the African lakes of the El Kef section of Tunisia. This has long been known to contain one of the most complete and best preserved fossil records of the Chicxulub extinction event and the continuous periods before and after the impact. In this case, temperatures were derived from the (relatively sensitive to temperature) ratios of oxygen 16 to oxygen 18.

https://www.space.com/40690-dino-killing-asteroid-impact-warmed-earth.html

Re: Chicxulub for the win!

Unread postPosted: Wed 20 Jun 2018, 11:52:43
by diemos
Uh huh. My guess for the start of the next glaciation is 200,000 years based on the dwell time of CO2 in the atmosphere and the Milankovich cycle.

https://upload.wikimedia.org/wikipedia/ ... dCores.png

Re: Chicxulub for the win!

Unread postPosted: Wed 20 Jun 2018, 12:00:45
by Plantagenet
KaiserJeep wrote:
The implication being: If human activity is increasing global temperatures, the outside bound for the healing period when FF combustion ends may be on the order of 100,000 years.


The CO2 we're putting into the atmosphere will be absorbed into sinks much more rapidly then that. Most will be absorbed in sinks within 1000 years, with a "long tail" of CO2 taking thousands or even tens of thousands of years to be completely absorbed.

common-climate-misconceptions-atmospheric-carbon-dioxide

Cheers!

Re: Chicxulub for the win!

Unread postPosted: Wed 20 Jun 2018, 12:26:24
by KaiserJeep
Plant, that "conventional wisdom" is exactly what the new information from the fossil record contradicts. While I understand that the world of 65 million years ago, and the mechanisms of carbon release then versus today are very different, the new information suggests that the healing period is "on the order of" 100,000 years. That means it is unlikely to be less than 10,000 years, and also unlikely to be more than 999,999 years.

The idea would be confirmed or disproved by other fossil isotope studies, which have not yet occurred. After all, there is NO SUCH THING as "settled Science" when it comes to the Theory of AGW.

Re: Chicxulub for the win!

Unread postPosted: Wed 20 Jun 2018, 14:37:40
by Outcast_Searcher
KaiserJeep wrote:The implication being: If human activity is increasing global temperatures, the outside bound for the healing period when FF combustion ends may be on the order of 100,000 years.

That assumes only natural processes occur.

That assumes no man made solutions, such as active technology based solutions already being researched and develop could be brought into play.

That's not a realistic assumption. Of course, the question is how much would such artificial/technological processes cost, and how cheap could they be made over time given the kind of scaling and refinements that technology tends to bring to manufacturing processes.

...

So the "Star Trek" technology COULD be brought into play if necessary, but how much would it cost, and would humanity be willing to pay the price?

My guess would be only if a strong majority of people can be convinced that it's in their best interest, and that it would make a meaningful difference short term (within their lifetimes).
The problem I see there is that the AGW effects would have to be VERY BAD before that is likely to happen, given how the problem is ignored today despite all the scientific evidence.

Re: Chicxulub for the win!

Unread postPosted: Wed 20 Jun 2018, 15:25:34
by diemos
Outcast_Searcher wrote:
That assumes no man made solutions, such as active technology based solutions already being researched and develop could be brought into play.


Active = Requires energy

You might notice the problem.

Re: Chicxulub for the win!

Unread postPosted: Wed 20 Jun 2018, 16:39:06
by KaiserJeep
No problem, we just dig a whole lot of coal and burn it for electric power....

Re: Chicxulub for the win!

Unread postPosted: Wed 20 Jun 2018, 16:58:58
by Plantagenet
KaiserJeep wrote:Plant, that "conventional wisdom" is exactly what the new information from the fossil record contradicts. While I understand that the world of 65 million years ago, and the mechanisms of carbon release then versus today are very different, the new information suggests that the healing period is "on the order of" 100,000 years. That means it is unlikely to be less than 10,000 years, and also unlikely to be more than 999,999 years.

The idea would be confirmed or disproved by other fossil isotope studies, which have not yet occurred. After all, there is NO SUCH THING as "settled Science" when it comes to the Theory of AGW.


Its a very interesting scientific study, but I always put more weight on studies on modern processes and recent geologic events then I do on studies from the distant past because we know far far far more about the way modern processes operate then we do about the distant past. In particular, the exact timing and duration of things that happened 65 million years ago is very difficult to determine. Radiometric dating methods used for rocks that old always have an "error" and this error will be much larger than the entire 100,000 year interval that is purportedly being dated. Unfortunately the news article in the citation doesn't actually describe how the timing of the 100,000 year long interval in the study was supposedly determined. Maybe someone has a link to the actual paper in SCIENCE?

Cheers!

Re: Chicxulub for the win!

Unread postPosted: Thu 21 Jun 2018, 12:59:17
by GHung
Plantagenet wrote:
KaiserJeep wrote:Plant, that "conventional wisdom" is exactly what the new information from the fossil record contradicts. While I understand that the world of 65 million years ago, and the mechanisms of carbon release then versus today are very different, the new information suggests that the healing period is "on the order of" 100,000 years. That means it is unlikely to be less than 10,000 years, and also unlikely to be more than 999,999 years.

The idea would be confirmed or disproved by other fossil isotope studies, which have not yet occurred. After all, there is NO SUCH THING as "settled Science" when it comes to the Theory of AGW.


Its a very interesting scientific study, but I always put more weight on studies on modern processes and recent geologic events then I do on studies from the distant past because we know far far far more about the way modern processes operate then we do about the distant past. In particular, the exact timing and duration of things that happened 65 million years ago is very difficult to determine. Radiometric dating methods used for rocks that old always have an "error" and this error will be much larger than the entire 100,000 year interval that is purportedly being dated. Unfortunately the news article in the citation doesn't actually describe how the timing of the 100,000 year long interval in the study was supposedly determined. Maybe someone has a link to the actual paper in SCIENCE?

Cheers!


http://science.sciencemag.org/content/e ... ce.aap8525

I'm sure a preeminent scientist, such as you, are has an account with Science. Check it out and let us know.

Abstract

Greenhouse warming is a predicted consequence of the Chicxulub impact, but supporting data are sparse. This shortcoming compromises understanding of the impact’s effects, and it has persisted due to an absence of sections that both contain suitable material for traditional carbonate-based or organic-based paleothermometry and are complete and expanded enough to resolve changes on short time scales. We address the problem by analyzing the oxygen isotopic composition of fish debris, phosphatic microfossils that are relatively resistant to diagenetic alteration, from the Global Stratotype Section and Point for the Cretaceous/Paleogene boundary at El Kef, Tunisia. We report an ~1‰ decrease in δ18O values (~5°C warming) beginning at the boundary and spanning ~300 cm of section (~100,000 years). The pattern found matches expectations for impact-initiated greenhouse warming.

Re: Chicxulub for the win!

Unread postPosted: Thu 21 Jun 2018, 17:08:56
by rockdoc123
I took a quick look at the paper. Basically, they are not using isotope data for dating because they are looking at an interval of depositional time associated with an event that is well-constrained age wise. According to the paper they have a continuous sedimentation rate over the interval in question (they reference work from another paper in that regard) and the interval is known to be free of erosion or sedimentary bypass. Hence they take the thickness and sedimentation rate to derive the 100,000 year time interval. Temperatures are determined by oxygen isotope work.

Re: Chicxulub for the win!

Unread postPosted: Thu 21 Jun 2018, 17:13:15
by KaiserJeep
Reading between the lines here, the assertion that a period of recovery from a runaway Greenhouse condition is possibly 100,000 years versus 1000, is seemingly credible.

We won't be the same species by the time the planet will again support a diverse ecosystem.

Re: Chicxulub for the win!

Unread postPosted: Fri 22 Jun 2018, 01:22:18
by onlooker
Life After Death: 'Great Dying' Recovery Took 10 Million Years
https://www.livescience.com/20598-mass- ... overy.html
Maybe, one of you sage members can comment as to how accurate this figure may be and how much correlation it may have with the catastrophic conditions unfolding now