"The next Ice Age!" Topic

link

That is a fascinating page. Should put the fear of the wrath of God into you!

Looks like old earth has spent most of her time sleeping under a blanket of ice. Sort of the same proportions to "waking" as a little baby. But the mean temperature has been steadily increasing, which maybe means that in geologic terms the earth is reaching "toddler" age. Still, it does look like we are going to get another Ice Age rather soon.

What percentage of the earth's population would survive, do you think? And would our technology survive with the remnant of humanity?

I understand that when the icecap is building that it is a quick phenomenon. So furious are the storms at the poles, that they literally suck up the moisture into themselves. At the advancing edges of the icecap, the rate of speed is faster than a man can walk.

I would not mind an ice age exactly… we have done so much damage to this planet that it would be good if it was able to "reboot". Global warming will not allow a reboot… that will simply kill everything!

"Looks like old earth has spent most of her time sleeping under a blanket of ice."

No that's not what the article says. It says that most of the last 450,000 years has been spent under an ice blanket with short "interglacial" periods throughout. Half a million years is long to us but not that long to a 4.5 billion year old planet.

The Triassic, Jurassic and Cretaceous periods (time of the dinosaurs) went from 450 to 75 million years ago. In that time most of northern Canada (such as it was, the continents were different) had a tropical climate. Not a glacier in sight. In fact dinosaurs lived in Antarctica. For a few 100 million years the world was HOT and the poles were temperate!

The last glaciers receeded about 15 thousand years ago. This article only deals with the Pleistocene period. Oxygen isotope ratios are used to determine ice ages. There have been at least 44 such periods in the last 2.5 million years.Who knows how many in Earth's history?

Why do the cycles come about? Ya, like the article says, the answer is astronomical. The leading culprit is Milankovitch cycles which are deviations in Earth's orbit around the sun. Or it could be lack of sun spot activity within the Sun. That explained the "mini-Ice age" in the 1600's. Oddly enough, the last Ice Age, in the Pleistocene, can't be explained by Milankovitch cycles.

Anyways, we are still going towards the main section of the interglacial period. That is why the temperature has been rising: see fig.1-4 and 1-5 in the article. Anyway we won't have to worry about it Humphrey, we won't be here.

Ralph

More like the wrath of nature.

Gasp, you mean, global warming is not the result of man's inhumanity towards nature!

What will all the environmentalists do?!!

Global warming is an observable fact. Causes are the subject of continued, and often (ahem) heated, debate. Whether knowing the causes will help us or not remains to be seen.

And I wouldn't count on not being around for this to matter. Some of the observed "snaps" from one global climatic state to another have taken as little as a couple decades, based on the ice core records, and just because we are trending one way now doesn't mean we can't flip back. That type of backlash is one of the things environmental scientists worry about the most, because we could be tooling up for warmer, higher seas when the ice knocks in the back wall…

In the '70s, it was Global Cooling. Then it was Global Warming. Are we back at Global Cooling again?

Back a few years ago there was talk among scientists about the possibility of global warming shutting down the "trans-atlantic converor" mechanism that powers the gulf-stream to europe, resulting in western europe having temperatures more in line with corresponding latatudes of western canada. Has anyone seen anything on that of late, or has it been discarded?

Jeepers…haven't any of you folks watched 'ICE', or 'The Day After Tomorrow'??? IF the sun's output were to decrease by JUST a few percent…or the 'salinity' of the oceans reached a 'crisis' point due to 'global warming'…the climiate could indeed 'reboot'.

That's why studying weather systems on earth, VENUS, Mars, Jupiter and such are all part of helping us to understand our own world/weather patterns….

Speaking of Antarctica, did anyone hear any more about the folks that were going to drill down to that 'Lake Erie' sized body of water there…that has been 'under the ice' for about 2 million years??? What kind of life could have survived there…bacterial/fungus/viral, etc?? And what will happen to it when it is EVENTUALLY 'exposed' to current conditions? Will it grow/multiply like 'red tide'…or be 'snuffed out' like the dodo??? (especially considering the 'ozone hole' that forms there???)

Here's another argument for off-world colonies…and 'seedships' to other systems…(in case our sun were to nova)…or what if there is a super-nova within…say, 100-500 lightyears??? What effect would that have on life here???? Didn't a nearby nova once be considered a possible reason for the dinosaurs being extinct…or ONE of the 'mass extinctions'???

and forget about trying to use nukes to deflect glaciers/melt them…we'd exhaust our stockpiles without doing more than making a dent…actually ADDING to 'nuke winter'…*sigh*…

Lets move to PLUTOS…always a 'balmy' -275 to just above absolute zeros…and plenty of BUGS to kill!!
Lt DWW…

I believe the hot Antarctica idea is mainly due to continental drift which placed the continent much closer to the equator during dinosaur age.

But I'm no paleoclimatologist so don't count on that to be the absolute truth.

"The Triassic, Jurassic and Cretaceous periods (time of the dinosaurs) went from 450 to 75 million years ago."

crhkrebs , The Mesozoic was from about 251 million years ago (Mya) to 65Mya but otherwise what you said is good.
In general most of the Phanerozic (time with complex life from the Cambrian till now) has been characterized by warmer temperatures than now.
See this picture: picture
from scotese.com
There have been many times in the past with no ice caps at all. Late Cretaceous for example has coal swamps and alligators at the poles. The entire Midwestern US was under a 100m or so of seawater.
The coldest the Earth has even been was during the "Snowball Earth" period from about 750 to 630 Mya where so much ice formed that the white ice reflected sunlight, causing more cooling and more ice etc. till the Earth was covered in Ice hundreds to thousands of meters thick. Buildup of gasses from volcanoes eventually melted the ice. A "Slush ball Earth" is more likely, where it got very cold but didn't freeze over completely, just lots of glaciers + sea ices. Recent sediment cores from Brazil support this. Also photosynthetic life survived which is pretty good evidence too.

One theory I recently saw a lecture on was that the little ice age was caused by Europeans wiping out 95% of the Native Americans, allowing forests to regrow on the land the natives were using for agriculture. Forests remove CO2 from the atmosphere and thus cause cooling. There are a couple other reasons trees cause cooling though I can't recall what they are.

Re: the Antarctic lake, I haven't heard any more than I previously posted. The scientists involved were trying to find a way to sample the lake without contaminating it.

haven't any of you folks watched 'ICE', or 'The Day After Tomorrow'???

No, but I did see Two Days Before the Day After Tomorrow

"Shouldn't we be trying to help those people?"
"We don't have time, we need to figure out who to blame"

Norrmeister, depends on the time you're talking about. For the most part though, a warm Antarctic has been due to warm climate. Antarctic has historically spent a lot of the last half billion years hanging around the pole.

"Global warming is an observable fact."

Agreed. Though how much of that is due to human intervention and how much of that is actually part of the cycle, I think we will never know.

Call me chaotic (B5 Shadows), but I think these cataclysmic changes will eventually produce stronger, fittest individuals and collectives.

CC

We're still contributing to global warming and certainly polluting the planet – especially whislt we still insist on using petrol as we do in such vast amounts and don't seem to want to look for alternatives.

As a side note, it has been proven that glacial melting ( often quoted as one of the signs of global warming), ncreased before 1800, too soon to blame the industrial age effects on the environment. Doubtless, we are adding to the warming effect in a huge way, but a warm phase had begun at least 200 years ago, and most like had started before 1800, that is the approximate date when the evidence is provable.

Hi Rex,

Yes you caught with:"The Mesozoic was from about 251 million years ago (Mya) to 65Mya …" I was typing after a long day and spelling every second word wrong. Never checked the numbers though.

Also the dinosaurs really only showed up at the end of the Triassic, they really started to shine in the Jurassic.Oddly enough, the dinosaurs depicted in "Jurassic Park" were all from the Cretaceous. I guess both Crichton and I can get our numbers wrong.

Ralph

See this link: link

A bit on the heavy side, but it's summary is that over the last 500 million years, the level of CO2 does not seem to correlate with global temps.

And here's a quote from a USGS website:

Climate-related sea-level changes of the last century are very minor compared with the large changes in sea level that occur as climate oscillates between the cold and warm intervals that are part of the Earth's natural cycle of long-term climate change.

I remain skeptical of the climate change/global warming crisis.

According to the cult of the Flying Spaghetti Monster (www.venganza.org), global warming is inversely related to the number of pirates. They have a nice graph showing the linear relationship between the decrease in the number of pirates over the last 200 years versus average global temperature increase.

Would that be "pirates" as defined by peg-leg, eyepatch and one word vocabulary?

If not, considering how few people pay for the computer games they're playing, I'd say there were still pirates around. They just say "pwn" instead of "arr."

"They have a nice graph showing the linear relationship between the decrease in the number of pirates over the last 200 years versus average global temperature increase."

I don't knowabout that: piracy is alive and well off the coasts of Asia, and what about that cruise ship incident in Somalia recently? Maybe modern pirates don't count due to a lack of eyepatches, cutlasses, parrots, hornpipes or rum.

When my daughter was very young, here understanding of historical ages was dinosaurs, followed by pirates, then the present day.

"We're still contributing to global warming and certainly polluting the planet – especially whislt we still insist on using petrol as we do in such vast amounts and don't seem to want to look for alternatives."

Aliensurfer, what you say is undoubtably true but unfortunately doesn't involve the periodic warming and cooling we are talking about which is working along geological time scales.

"One theory I recently saw a lecture on was that the little ice age was caused by Europeans wiping out 95% of the Native Americans, allowing forests to regrow on the land the natives were using for agriculture. Forests remove CO2 from the atmosphere and thus cause cooling. There are a couple other reasons trees cause cooling though I can't recall what they are."

The mini Ice Age started in 1600. Wouldn't that be a little early to have mature forests heating up the Earth via C02?

By the Renaissance heliographs were monitoring the sun. The Mini Ice Age occurred during a period of low sun spot activity. This was correlated by the Chinese too. I think that is the leading contender, but again, in science, correlation does not equal causation.

Ralph

Cool discussion.

<rimshot>

groan.

Hi

Actually the "mini ice age" referred to here "One theory I recently saw a lecture on was that the little ice age was caused by Europeans wiping out 95% of the Native Americans, allowing forests to regrow on the land the natives were using for agriculture." Was also called "the year of no summer".

Unfortunately for these theories is that there were similar dips in the 400s ad and an unpleasent decade that was colder around 1385 in Europe, both pre-dating this supposed killing off of the noble american natives.

Anyway, HG, the paradigm keeps shifting. As was mentioned above, as a greepeace member in 70, I had it proved to me beyond a reasonable doubt that our pollution was producing a new ICE AGE that would strike by Y2K. And, at that time it was suggested that oil would cease to be a problem at the same time as we would have used it all up. No cars.

Then global warming, then about 10 years ago, global cooling/"hocky stick" global warming, and now evil agriculture causes global warming.

In my cynical old age, I would just be writing this off except that people keep wanting to make decisions on this stuff. Worse, my Beloved Scientific American, my favorite magazine since I could read, blithly prints all these contradictions as fact, and promotes politics with it.

Rocky

When I was 12, my science teacher explained to me that we only had about 50 years of breathable air left in the the atmosphere. At the rate that "Industry" was polluting the air, there would be nothing left. I dont make a habit of correcting my elders but if I could meet up with him again, I'd bitchslap that pervert for scaring the bejezus out of an adolescent.
13 years to go on his appocalyptic prediction and I see no evidence of having any less breathable air.

Les Howie-"Back a few years ago there was talk among scientists about the possibility of global warming shutting down the "trans-atlantic converor" mechanism that powers the gulf-stream to europe, resulting in western europe having temperatures more in line with corresponding latatudes of western canada. Has anyone seen anything on that of late, or has it been discarded?"

Yep, that idea is still around and it is a concern. Unfortunately, second order effects like that are even harder to predict. We probably know even less about the oceans than we do about the atmosphere. So this scenario is anyones guess right now – although it is a posibility.

Scenarios like this is why scientists are now speaking of "climate change" rather than "global warming" or cooling. Once you start messing with a system as complex as the environment all sorts of surprising results can start popping out.

I dont know about this global warming, but it was bitter cold this morning when I put the rubbish out, I stayed in til after lunch…..

"Unfortunately for these theories is that there were similar dips in the 400s ad and an unpleasent decade that was colder around 1385 in Europe, both pre-dating this supposed killing off of the noble american natives."

I think that, like D Stokes said, the climate is too complex to simply say "stop driving cars and things will be fine" or other such statements. That being said, supporting the simplistic "kill people to cool the climate" theory, during the Peloponnesian War around 430 there was some sort of plague and the mid 1300s was the peak of the Bubonic Plague so both of the instances match the cooling you mentioned.

The guy whose lecture I attended wrote a book called "Plows, Plagues, and Petroleum" if you want to read what he said. I don't remember his name.

"We're still contributing to global warming and certainly polluting the planet – especially whislt we still insist on using petrol as we do in such vast amounts and don't seem to want to look for alternatives."

Then we'd better hope nobody figures out how to make a gravity-powered perpetual motion machine. Some of the wild theories out there is that such machines would slow down the earth's rotation (!?!) and/or deplete the earth's gravity (!!??!!)
(Yes, some people actually believe that!)
Darned if you do & darned if you don't…. ;)

The Mini Ice age of the 1600s actually began in the 1300s (Probably the late 1200s come to think of it)…

It is thought to be a contributor to the bubonic plague…

About everything else….

I just know that when I was about 10 years old, we went to see the Glaciers in Washington and Alaska.

When my little sister goes to Alaska to work during the summers she takes pictures of some of the same glaciers that we visited in the 1970s. One of them has retreated about 10 miles…

It takes a bit of warming up to move a glacier back 10 miles. The rest of them have retreated quite a bit too. There are several bays that have opened up to navigation in Alaska due to Glacier retreat…

Now, wether the warming will continue until we bake in the heat, or whether the water will shut down the oceanic conveyors (There are three major conveyors and abut a dozen minor ones) and we will freeze to death…

Who knows.

I just know that I am going to be spending the next 25 years preparing for any such eventuality, as those who are well off enough will survive any such ill event, and those who are poor and unable to help themselves from such minor geological events as a relatively small hurricane will perish…

The world is just too populated is my feeling. About 1 in 3 of us needs to go unless the wealthy are more willing to release much of the horded wealth that they have and begin to take better care of those who are less off, which includes educating many of those who are less well off so that they can begin to take up some of the slack themselves…

All in All… the world will be fine.. It is humanity that is in danger…

All this giving by those that usually work for it to those that dont have, is called communism Judas….Well I wonder who actually is going to give their wealth away first. And what is considered wealth. It may mean different things to different people.

I dont recall seeing the likes of Geldoffs houses and grounds teaming with refugees living a better life thanks to his generocity. Its all self gratification to say the rich (who ever they are) should share more with the poor, but do very very little about it.

Nature is above all the human retoric and its rules are brilliantly simple, 'the stronest and most adaptable survive'

Hammer, I've already spoken about the simplistic view of Darwin's theory that you are espousing and how it fails to account for the environment the organism lives in, so I'll let that slide.

Interestingly enough, no-one has yet made mention of the fact that global warming may yet trigger an ice age. Think about this: Warmer weather leads to more evaporation in parts of the globe, and increases overall atmosphereic humidity. The air reaches saturation point, which leads to more precipitation; Even with the warm temperatures some of that will be snow in the higher latitudes. The effect of snow is to reflect away radiant heat from the sun, so if the snow persists, the area of the snow will cool down . . . Leading to more of the atmospheric water coming down as snow.

It's the Gaia effect in a sense. Question is, will the human population "weather" this readjustment if it goes into oversteer?

So I thought MORE sunspot activity…made for a 'cooler' climate….as sunspots are 'cooler' spots on the sun/decreasing overall solar radiation….

So does the '11-year sunspot cycle' have any bearing on climate changes…or is there a larger/longer sunspot cycle that does…?? I know axial tilt, salinity in water….volcanic eruptions/meterorid impacts…all have some bearing….
Lt DWW

Covert Warus said…..
Hammer, I've already spoken about the simplistic view of Darwin's theory that you are espousing and how it fails to account for the environment the organism lives in, so I'll let that slide……

Uh? I did'nt know my comment on not giving wealth away was a Darwinian theory, I thought it was more Dickensian / Scroogian :o)

Hammer, that was rather good, I may use that one against Creationists. Though since Dickens and Darwin were almsot contemporaries it could turn nasty….

It is obvious to preserve humanity that the most prosperous governments and corporations should seek to flee this failing planet after terraforming the Moon, Mars, Venus, and Mercury. Hopefully the Imperial Explorers will not investigate Pluto and break the seal of repulsion buried deep under the surface. But I'll be long gone by then so maybe I'll just return as part of the Dark Symmetry.

If Technology that deals with replacing organic tissues with silicon or other hybrid technology continues at the state that it is in now… We could see the rich leaving for the belt by the middle of this century, and those who have a bit more patience setting off for the nearest stars by the end of it…

Once the singulairty is passed, of course, there will be no telling what "we" will be capable of…

I know that if I am still around at the event of the singularity, that I will be moving to a less gravity ridden place. Someplace with a nice view of Jupiter and the Megellanic clouds… Or Maybe Saturn and the clouds… Get myself a few nice asteroids to mine for water and metals… Etc…Maybe pay for a few unaugmented "humans" to get upgraded in return for indentured servitude… and so on…I could probably build dedicated robotic peripherals easier though, but you never know when you might need an actual organic brain for something or another though…

Some random witterings…

When you are talking about CO2 levels over hundreds of millions of years, you also have to consider the fact that the sun has been getting steadily brighter and hotter over millions of years. Meanwhile living things have been happily removing CO2 from the atmosphere and turning it into rocks (limestone and fossil fuels) for millions of years.

The combination of the increasingly hot sun and the diminishing CO2 have kept the Earth's climate pretty stable. Ice ages are a minor glitch. Hot sun without the CO2 removal and we'd have fried like Venus. Remove CO2 without the sun brightening and we'd turn into a permanent snowball Earth.

A full-on Greenhouse climate (no ice caps at all, no life in the deep oceans due to lack of oxygen there) is Earth's 'default' state. That's the way it's spent most of geological time. What we are in now is an Icehouse climate (ice caps present, lots of life in the deep oceans).

When people talk about the effects of global warming, they usually mean going from medium sized ice caps to small ice caps, not a switch to a full-on Greenhouse.

Goldwyrm – if you can terraform Mars and Venus, you can terraform Earth back to pre-global warming state!

Exactly…

"Interestingly enough, no-one has yet made mention of the fact that global warming may yet trigger an ice age."

That's the "backlash" I mentioned. I choose not to go into specifics because I'm not a climatologist, and even those who practice that branch of meteorology/oceanography/geology don't really know if or what. The erudite can posit an effect, while the truly worried realize the butterfly's wings can flap either way…

Farstar, you speak the truth.

In fact this past week there is evidecne that the Gulf Stream may be collapsing again, and Western Europe may becoame colder over the next decades.

Battlefield 2142 is exactly it.
link
link

Cool video clips!

CC

Anyone see this cheesy 1998 made-for-tv film called "Ice"?

imdb.com/title/tt0160393
link

CC

Just curious . . .

Anyone done anything like Battlefield 2142 but with minis?

CC

Having interesting weather at your place this week, CC? All the climatology topics from (looks at the top of the page) THREE years ago seem to be floating back to the surface…

Yep. One day cold, then hot, then cool, then warm, then . . .

LOL. I know "weather happens" (we are in "brief" interglacial period after all), but I can't help wondering about extremes when weather outside changes so much.

CC

"…to be floating back to the surface…"

My only comment – How appropriate.

Let me stir the pot.

junkscience.com

Not that I agree or disagree with all on this site.

I do find it strange the Religion of Science is so sure the Religion of <fill in the blank> is so unscientificly based on faith when something that cannot be confirmed by repeated independent experiments must be accepted as fact or the "unbeliever" is pilloried as happens so much when laymen attempt to promote political actions on the basis of such "science."

Gtacias,

Glenn

I'll leave now before I gather too many stifles or be tempted to return to stifling others again.

Why thank you ever so much Warbeads. This WAS a friendly thread…