Not years. Months. We really need to be thinking about climate control in general, instead of how to punish carbon emitters.
20 thoughts on “How Long Does It Take An Ice Age To Start?”
Comments are closed.
Not years. Months. We really need to be thinking about climate control in general, instead of how to punish carbon emitters.
Comments are closed.
Mammoth investments in actual construction of nuclear is one of the few options that are useful in all the possibilities: Warming, Cooling, Neither, Clueless.
Dam the Bering Strait I say!
At a glance, it appears that a few centuries of cooling was triggered by a massive influx of fresh water (much greater than the water in the current Great Lakes) to the Arctic Ocean. The only thing capable of that these days is massive melting of the Greenland icecap. There’s no other freshwater source of that size in the Northern hemisphere.
I dunno. I’m skeptical of mastering climate. I prefer working on adaptability instead. We didn’t colonize Greenland by trying to warm it up — we wore warm wooly clothes. W are likely to colonize the Moon not by attempting to provide it with an atmosphere, but by wearing spacesuits and building domes and tunnels.
In general, climate is not something, within wide variation, we need to concern ourselves. We can live perfectly well in the Arabian desert with 110F daily temperatures, or in Alaska with -40F daily temperatures. It’s just a question of your air-conditioning or heating bill, and what you wear outside.
What’s critical is only farming, because that depends on less adaptable lower creatures. So we should learn to be more flexible in our food sources. Learn to grow stuff in the ocean, or whatever. On the whole I’m not super worried. Farming is not all that tricky, and barring a Snowball Earth event, there will be somewhere on the globe where we can grow the food we need to feed us.
Indeed, I suspect the real issues will be political. If the Earth warms and Canada becomes the breadbasket while the US becomes Sahara-like desert, or if Brazil and India become temperature gardens while the US and Europe go into the deep freeze,this bespeaks major political instability.
I believe Karl is correct — and there is this from Rand’s link:
JUST months – that’s how long it took for Europe to be engulfed by an ice age. The scenario, which comes straight out of Hollywood blockbuster The Day After Tomorrow, was revealed by the most precise record of the climate from palaeohistory ever generated.
Around 12,800 years ago the northern hemisphere was hit by the Younger Dryas mini ice age, or “Big Freeze”. It was triggered by the slowdown of the Gulf Stream, led to the decline of the Clovis culture in North America, and lasted around 1300 years.
How do you slow down the Gulf Stream? Add large amounts of fresh water.
Where does the fresh water come from? Glaciers which melt.
But yes, we need the ability to ratchet down or up carbon emissions if we are to do planetary engineering.
Right now we lack the ability to ratchet down carbon emissions.
@ Pete
Closing the straits of Gibraltar and / or opening a clear passage through the isthmus of Panama (excavation with nuclear explosives would likely be necessary) is one proposal to re-start ocean salt circulation if the Gulf Stream shuts down.
And!
This reminds me of the Lake Michigan Stonehenge possibly built by the Clovis people before that ice dam flooded them out more than 12,000 years ago
http://michpics.wordpress.com/2009/01/13/underwater-images-of-a-lake-michigan-stonehenge/
Related, I saw a cool paper about how certain northern Wisconsin valleys were carved by a sudden onrush of water from Lake Superior into Lake Michigan.
I’m with Mr. Pham. From an engineering perspective, “Igloos for everyone!” seems a lot more doable than actual geo-engineering. We just don’t know enough about how the climate works to go messing with it. For all we know ratcheting down CO2 would have no effect at all (or too little, too late), while building proper shelters is much more likely to be successful.
—
OT, the Clovis culture wiped out by the discussed Ice Age was named so after its signature technology – the Clove-shaped spear head. I wonder what a future archaeologist would call our century? The Hydrocarbon Culture? The Silicon Culture?
Maybe all future cultures will be categorized by their Energy Source-Computing Medium technologies. Hopefully we’ll graduate to the Fusion-Optical Culture soon.
“For all we know ratcheting down CO2 would have no effect at all ”
Actually, for all we know, it’s quite the opposite. We know quite a bit. For all you know, it might not.
OT, the Clovis culture wiped out by the discussed Ice Age was named so after its signature technology – the Clove-shaped spear head. I wonder what a future archaeologist would call our century? The Hydrocarbon Culture? The Silicon Culture?
I pick “hydrocarbon culture” which is slowly transitioning to something else. “Silicon culture” sounds ok, though I think “information/knowledge culture” would be more accurate since there’s a current emphasis on less tangible goods and services.
Brock,
if they find evidence of Obama being elected, Schmuck Culture.
There’s a tie-in here to another of Rand’s (and my) favorite subjects; search on “Clovis Comet.” That ice age that started in a few months may have been kicked off by an impact.
opening a clear passage through the isthmus of Panama (excavation with nuclear explosives would likely be necessary) is one proposal to re-start ocean salt circulation if the Gulf Stream shuts down.
Now that is an interesting challenge to the lover of the back of the envelope.
A quick trip to Google for “nuclear excavation” turns up Operation Plowshare, in which, during the “Sedan” test, a 104 kt blast produced a crater 100m deep by 390m across. Assuming this has the shape of a section of a sphere (which trigonometry tells us would have a radius of 811m), we find that the volume excavated was 4.7×10⁵ m³, for a net excavation of 4700 m³/kt.
Another trip to Wikipedia — I love the Internet! — tells us the Panama Canal is 77 km long, and it’s relatively straight, so the problem as set is to dig a 77 km long ditch. But how wide and deep? Bill White does not say, but I presume the task is to produce a substantial flow of water, one that can compete with the Gulf Stream. The Gulf Stream has a current of about 2.5 m/s over a frontal area of 100 km x 0.8 km = 80 km². Let’s assume we can get treble the current (17 MPH or so, quite a mill race), and we only need to move 1% of the water: that means we need a frontal area of 1/300 of the Gulf Stream, or 0.26 km². That corresponds to a channel 100m deep by 2.6 km wide. Very impressive!
We therefore need to excavate 77 km x 0.26 km² = 20 km³ or 2.0×10¹⁰ m³, alas. At 4700 m³/kt we need 4.2×10⁶ kt or 4200 Mt of nukes. A typical warhead in the American arsenal is 300 kt. We’d need 14,000 of these, which we no longer have. At the height of the Cold War we had maybe 20,000 warheads, although a fair number were smaller than this, and a few larger.
So, roughly speaking, it seems possible, although it would take the entire Cold War arsenal of the United States. The problem of the rather spectacular levels of radioactive fallout, not to mention the nuclear winter hypothesis, are left as exercises for the class.
Carl, I truly appreciate the math; yours was probably the most enjoyable comment I’ve read in weeks.
In the real world, in the rather unlikely event that an existential threat could be addressed only by dramatically enlarging the Panama Canal with nuclear explosives, I would expect them to be buried deeply enough for subsidence, rather than excavation, to create the new channel.
In this connection, weapons designer Ted Taylor once proposed that shaped-charge nukes be developed and used to dig very long, straight tunnels very quickly. Also, some nukes are cleaner than others.
As with many such discussions, engineering and radiochemistry are relatively minor problems by comparison with politics and public attitudes.
According to my wife, it takes about 30 minutes after I turn on the A/C in the house, or 2 minutes after I turn it on in the car!
Brock Says: “We just don’t know enough about how the climate works to go messing with it.”
And, when you try to control an only partially known plant, things oft go awry.
There was a source of sufficent freshwater to have the required effect. It was probably from the partial draining of Lake Agassiz. I’m a bit suprised at it happening so quickly but it occurred at the right time.
Nothing quite like that can occur today. The Greenland Ice Sheet cannont melt extremely quickly because the glaciers have to flow out through gaps in the mountains. The danger of a rapid melt is in the Antarctic where part of the West Antarctic Ice Sheet could fragment in place and calve lots of icebergs. It appears to have happened before. This is more likely to take decades than months.
Unless we get a big enough impactor in the right place. ;^)
I agree with the first commenter. if only the mammoths invested in nuclear power, they’d still be around and not frozen solid. Learn from the mammoths!
We don’t need to excavate the entire sea level connection ourselves. Once we’ve dug deep enough and wide enough for any current to flow from the Pacific to the Atlantic, it will scour a deeper and wider channel more effectively than we ever could.