Cause of the melting of the last Ice Age?

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I don’t even believe there was an Ice Age. I do believe there was a world-wide Flood and that this is the reason for ice-age-like effects we see.
 
Man wasn’t around, so I can’t offer anything in the way of a plausible theory. If human activity is the main culprit in AGW, what was the culprit some 2 million years ago? Perhaps human predecessors were big on CO2-emitting activities.🤷 Perhaps they put their groceries in plastic bags? Perhaps their primitive means of transportation weren’t fuel-efficient? Or what was going to kill us all in the 80s, and then vanished magically, i.e. acid rain, was a real problem back then? I mean no Ice Age can withstand the deadly force of acid rain:
Code: 
                      Rain, acid rain
                      Burning bright in the forests of the night
                      What immortal  hand or eye
                      Could frame thy fearful PH?
 
Jim_Baur said:
What were the causes of the last Ice Age?

THANKS!
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Positions of the planets. Tilt of the earth was different. Man Was around during the last Ice age about 20,000 years ago. 20,000 years from now there will probably be another ice age. Right in the middle was the renassance. The movement of the 7 spirits before the throne his ministers affect these things.
 
There is not a straightforward answer. Glaciations*, in time periods that have them, are generally attributed to Milankovitch cycles, long-term (the cycles are ~26,000, ~40,000, and ~100,000 years) cyclical changes in the Earth’s orbit that affect the amount of energy the earth receives from the sun.

However, in, say, the Eocene ~50 million years ago, and for large parts of the Mesozoic (the dinosaur era), the Earth was so warm that there couldn’t be a glaciation regardless of the Milankovitch cycles. That (called “hothouse” and “icehouse” Earths) generally changes on a far longer time scale.

*A ‘glaciation’ is the technical term for what is colloquially called an ‘ice age’. ‘Ice age’ is ambiguous because it’s sometimes used for an ‘icehouse’ period, meaning one in which there is any significant permanent ice cover (as now in Antarctica and Greenland), and in which glaciations (and the warm periods between them, interglacials) can exist.
 
The first known ice age was about 600 million years ago when the Earth was completely covered with ice. I doubt very much that it will ever get that bad again. :eek: 😛 😃
 
bsroufek said:
I don’t even believe there was an Ice Age. I do believe there was a world-wide Flood and that this is the reason for ice-age-like effects we see.
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There is a proposed model where an ice-age followed the flood about 200 years later.
 
they say there were 20 ice-ages in the last 2.5 million years. if that helps any.
 
Jim_Baur said:
Have I understood correctly, they just do not know?
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No. They know. The problem, and I mean no offense, is that you are asking us and not them. There are dozens of factors that effect the climate of the earth from the obvious such as the current climate of the earth and the level of CO2 in the atmosphere, but also the amount of trees on the planet, solar cycles, the “wobble” of the earth on its axis, its proximity to the sun, etc, etc, etc, etc.

I just got a degree in geology. We actually covered ice ages a little bit, but even I don’t recall being taught the specific cause of the end of the last ice age. I know we’re technically in the middle of one now, which is being effectively “canceled” by global warming. The point being that your question requires a rather advanced and technical answer that you probably won’t find here. This is CATHOLIC answers, after all, not “climate answers”. 😛
 
In New Zealand recently they were concerned about the effect of farting animals on the ozone layer - it is a great farming country, and the methane levels were measurable and causing concern.

Perhaps the ice age was caused by the dinosaurs eating too many beans?
 
Falco said:
In New Zealand recently they were concerned about the effect of farting animals on the ozone layer - it is a great farming country, and the methane levels were measurable and causing concern.

Perhaps the ice age was caused by the dinosaurs eating too many beans?
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I’m starting to read a book “Clean Energy, Climate and Carbon” by Peter J. Cook (CSIRO Publishing).

He allocated the following “global warming potential” over 100 years on a per molecule basis as follows -

Carbon Dioxide 1
Methane 25
Nitrous Oxide 298
HFC Refrigerants 1430
Carbon Tetrachloride 1400
CFC Refrigerant 10900
Suphur Hexafluoride 22800

Which means that Methane has 25 times the potential as a Greenhouse Gas (GHG) compared to Carbon Dioxide on a molecule to molecule basis.

When sunlight hits the earth, a lot is reflected back out into space.as infrared radiation, much like a radiator used to heat a home. The net energy supplied by the sun is therefore the solar (name removed by moderator)ut less the reflected radiation.

What GHG’s do is to trap this reflected energy, and retain it in the atmosphere. The biggest contributor to the Greenhouse effect is water vapour in the atmosphere, but there is no evidence that mankind has contributed to any significant increase in water vapour.

But while Methane has 25 times the inherent GHG ability of carbon dioxide, it is at significantly lower concentrations (about .45% compared to CO2, if my interpretation of a graph in the book is correct) which would equal about 11.25% of the effect of carbon dioxide.

We are pumping increasing amounts of CO2 into the atmosphere, and I think it is having a gradual greenhouse effect. That’s why the debate tends to focus on CO2 and not the other gases or water vapour. The water vapour does not appear to be changing (at least not by man’s efforts) and the other GHG gases are in small concentrations.
 
“Over a 95,000 year cycle, the earth’s orbit around the sun changes from a thin ellipse (oval) to a circle and back again. When the orbit around the sun is most elliptical, there is larger difference in the distance between the earth and sun at perihelion and aphelion. Though the current three million mile difference in distance doesn’t change the amount of solar energy we receive much, a larger difference would modify the amount of solar energy received and would make perihelion a much warmer time of the year than aphelion.”

so maybe ice-ages are here when the earth is in its most elliptical orbit. which would make very cold winters in the northern hemisphere and cool, if not cold short summers also.:winter:

and the ice-age ends when earth regains a circular orbit again.
but these changes in orbit sound very gradual and i seem to remember that the interglacial periods were short 20,000 year periods compared to 80,000 - 100,000 year glaciation periods. 🤷

so perhaps the earth does not have to move much in its orbit to begin a major ice-age, but it needs to be as close to the sun as possible in a circular orbit to end an ice-age.
 
Now what about the grand canyon. It’s clearly not water erosion is it but the push of glaciation in carving. I have a Trilobite fossil from the mountains before they were pushed up into mountains and were the ocean floor.
 
billcu1 said:
Now what about the grand canyon. It’s clearly not water erosion is it but the push of glaciation in carving. I have a Trilobite fossil from the mountains before they were pushed up into mountains and were the ocean floor.
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glaciers might leave horizontal deep scrapes in the sides of the canyon. the ice picks up stones and gouges the rock walls of valleys.

interesting, i could never figure out how the stone gouges such deep lines in solid hard rock…
 
billcu1 said:
Now what about the grand canyon. It’s clearly not water erosion is it but the push of glaciation in carving. I have a Trilobite fossil from the mountains before they were pushed up into mountains and were the ocean floor.
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Nope. The grand canyon was most definitely a result of water erosion. Glaciers carve, but nothing like that. There are also a dozen other indicators of the presence of glaciers, and none are present anywhere near the grand canyon.
 
tabycat said:
The first known ice age was about 600 million years ago when the Earth was completely covered with ice. I doubt very much that it will ever get that bad again. :eek: 😛 😃
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That was Snowball Earth, that’s different than what are commonly known as Ice Ages. Snowball Earth happened at least three times (in Earth’s history) 2.2 billion, 710 million years ago, 640 million years ago. They had longer period in between than compare to the Ice Ages happen periodically as Paddy said:
Paddy_Walker said:
they say there were 20 ice-ages in the last 2.5 million years. if that helps any.
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