Snowball Earth

[Neethis]

Heya people, heres my attempt at a Snowball Earth. I made it messing about in Paintshop for a lil while;





I might upload it to the motherlode if people like it

Constructive critisicism welcome, and yes I do know that its not completly scentifically accurate

[buggs_moran]

That's pretty neat. I think you left the coastlines too evident though. I would imagine that for all of the water to be locked up in ice that the coastlines would recede. I could be way off though. Did you do any research on it or was it a purely paintshop fun approach?

[Neethis]

Thanks, it was purely messing about

I hadnt given the coastlines much thought. If it was a slow freezing process, with the water precipitating onto the ice caps, I guess the coastlines would be much further out as sea level fell. However if it happened fairly fast, I would think the water would expand as it froze, right? Pushing the sea ice up onto the land

[PlutonianEmpire]

Cool. I made my own version about a year ago, but it was all ice, not a bit of rock peeking out.

You should upload your addon.

[ajtribick]

Maybe move the coastlines to the edge of the continental shelves. Wouldn't the high altitude regions be the first to get covered in ice though?

[Dollan]

A lot of the continents might actually be relatively ice free. That much water locked up as ice isn't going to leave much available to accumulate as ice or snow very far inland, and what might have formed early on in the beginning of the ice world process would probably have been ablated away by winds.

But, as a Paint Shop project, this is actually pretty cool. I'd load it up to the Motherlode, certainly!

...John...

[bh]

Yes...nice job....upload it please!

[Neethis]

Cool Ill send it in soon. Ill do some research and have a go at making a more scienfically accurate version too.

[buggs_moran]

One very interesting snowball earth site http://www.snowballearth.org/

On the other hand, a climate model predicted that if the 10-km-diameter asteroid that hit the Earth 65 million years ago extinguishing the dinosaurs and many marine lineages hit instead today, a snowball earth would result. This is because the present cold ocean is more susceptible to surface freezing than the warm Cretaceous ocean (when a snowball earth did not occur) during the decade of reduced Solar forcing due to dust thrown up by the impact.

At the height of the last ice age, a mere 21,000 years ago, much of North America and Europe were covered by glaciers over 2 kilometers thick, causing sea level to drop by 120 meters....(and further along)...In his model, once ice formed beyond a critical latitude (around 30 degrees north or south, equivalent to half the Earth's surface area), the positive feedback became so strong that temperatures of the surface plummeted, yielding a completely frozen planet. The relatively small amount of heat escaping from the Earth's interior is sufficient to prevent the oceans from freezing to the bottom, but would still allow a kilometer thick cap of sea ice to form, thicker at the poles and thinner at the Equator.

[eburacum45]

On a snowball Earth you would probably see cracking something similar to the ice cracks on Europa.
As I expect you know, one theory suggests that when the Earth was locked into a snowball scenario in the Neoproterozoic era, this situation remained only until the emission of CO2 from volcanoes increased the greenhouse effect and the ice melted.

In fact once the ice has melted the world might become briefly hot due to the high levels of CO2.
I have seen suggestions that the Earth alternated between hot and cold for quite some time in this period.
http://www.snowballearth.org/end.html

[Neethis]

buggs and eburacum, thanks for the resources.

[PlutonianEmpire]

My 2 cents:

I think that in a snowball earth event, deserts would likely remain ice-free, due to the fact that they don't get much moisture in the first place. I could be wrong though.

[Dollan]

My 2 cents:

I think that in a snowball earth event, deserts would likely remain ice-free, due to the fact that they don't get much moisture in the first place. I could be wrong though.

No, that's pretty much what I said, though it wouldn't just be the desert regions. Most of the continents would remain ice free, as far as the interior goes. Some of the snowball Earth papers detail this.

...John...

[PlutonianEmpire]

I see.

For some reason, I keep thinking that in the next snowball earth event, continents will have more ice cover than in previous events, due to the fact we have vegetation. Something about stomata and evaporation. Plus, I also know that for snow to form, it requires a dust particle to form around, and if the next event were to occur this decade, there would be plenty of snowfall to go around before all the moisture is sucked out of the air, because of all the dirt we've been pumping into the atmosphere.

[Don. Edwards]

Yes but that dust in the atmosphere is saving are collective buts right now. I caught an episode of NOVA on PBS that detailed the dimming of the sun. To put it in short, with the amount of global warming that has occurred already, if that dust wasn't up there we would have close to an 18 degree increase in temperatures right now. That would be devastating to everyone everywhere.
So at this time even though we are losing this dust due to cleaner air standards it?€™s a double edge sword. We take too much out of the atmosphere before getting the other green house gasses down we are going to be in some real trouble. So instead of a Snowball Earth we are going to go the other way, into a phase with no polar ice at all. We will all be swimming around in most of the planets big cities.

Don. Edwards

[Neethis]

Ooo yeah I saw that thing about Solar Dimming. Thank the Victorians for most of that carbon dust in the upper atmosphere lol. Producing cleaner burning fuels might be the worst thing we've ever done...

[Neethis]

Snowball Earth is up on the motherlode check the "Fictional/planets and systems" section to find it.