could another ice age happen?

[drychlick]

with all the talk about the earth geting hot could we have a new ice age happen? i just saw the history ch. show how the earth was made tonight and did a story about the least ice age! love dr

 

[All Seeing Eye]

Theory is that if enough ice melts and dumps enough freshwater in the Atlantic it will shut down the Gulf Stream stopping warm water and air from circulating northwards thus plunging most of the northern hemisphere into an ice age.

 

[Locutus]

Theory is that if enough ice melts and dumps enough freshwater in the Atlantic it will shut down the Gulf Stream stopping warm water and air from circulating northwards thus plunging most of the northern hemisphere into an ice age.

I saw that movie. Didn't turn out too well for Canada.

 

[Trekker4747]

Theory is that if enough ice melts and dumps enough freshwater in the Atlantic it will shut down the Gulf Stream stopping warm water and air from circulating northwards thus plunging most of the northern hemisphere into an ice age.

The first scientificly correct thing you've ever said.

"Could another ice age happen?"

Yes.

There've been five of them in Earth's some 5-billion year history. So it seems likely we'll get another one sometime in the next billion years or so.

 

[Scout101]

can, and will, happen. Short of us getting to the point where we can control things ourselves, bound to happen. natural cycles for the planet, slight orbital patterns, etc. Part of how the earth renews itself on occasion, as well.

 

[JiNX-01]

A slightly off-topic, but related matter:

I don't recall there ever being an ice age in the southern hemisphere. Anybody know if there has been and if not, why not?

 

[Birdog]

Hate to break it to y'all but we are still in an ice age.

From Wiki

The general term "ice age" or, more precisely, "glacial age" denotes a geological period of long-term reduction in the temperature of the Earth's surface and atmosphere, resulting in an expansion of continental ice sheets, polar ice sheets and alpine glaciers. An ice age is a natural system. Within a long-term ice age, individual pulses of extra cold climate are termed "glacial periods" (or alternatively "glacials" or "glaciations"), and intermittent warm periods are called "interglacials". Glaciologically, ice age implies the presence of extensive ice sheets in the northern and southern hemispheres;[1] by this definition we are still in the ice age that began at the start of the Pleistocene (because the Greenland and Antarctic ice sheets still exist).[2]

Thus global warming is natural.

 

[Trekker4747]

Hate to break it to y'all but we are still in an ice age.

From Wiki

The general term "ice age" or, more precisely, "glacial age" denotes a geological period of long-term reduction in the temperature of the Earth's surface and atmosphere, resulting in an expansion of continental ice sheets, polar ice sheets and alpine glaciers. An ice age is a natural system. Within a long-term ice age, individual pulses of extra cold climate are termed "glacial periods" (or alternatively "glacials" or "glaciations"), and intermittent warm periods are called "interglacials". Glaciologically, ice age implies the presence of extensive ice sheets in the northern and southern hemispheres;[1] by this definition we are still in the ice age that began at the start of the Pleistocene (because the Greenland and Antarctic ice sheets still exist).[2]

Thus global warming is natural.

Yeah, one of the "anti-global warming" things I hear is that it's the Earth still trying to come out of the latest Ice Age. Which I believe could very likely be. (Because, yes, we're still in an Ice Age.)

 

[PlixTixiplik]

A slightly off-topic, but related matter:

I don't recall there ever being an ice age in the southern hemisphere. Anybody know if there has been and if not, why not?

Aside from today (Antarctica is completely ice-covered), both the Ordovician glaciation and the late Paleozoic ice age were centered in the southern hemisphere. In the late Paleozoic ice age, glaciation was widespread over South America, India, southern Africa, Australia, and Antarctica. In addition, two of the three late Precambrian "Snowball Earth" glaciations included ice in the southern hemisphere, but ice was basically global then anyway.

 

[Tiberius]

Beaten to it, but we are still in an ice age.

 

[T'Girl]

Aside from today (Antarctica is completely ice-covered), both the Ordovician glaciation and the late Paleozoic ice age were centered in the southern hemisphere.

So some ice ages are primarily in the south and other primarily in the north? And some in both hemispheres?

 

[PlixTixiplik]

Aside from today (Antarctica is completely ice-covered), both the Ordovician glaciation and the late Paleozoic ice age were centered in the southern hemisphere.

So some ice ages are primarily in the south and other primarily in the north? And some in both hemispheres?

Yes, it depends on where the continents were located. In the Paleozoic, the supercontinent of Gondwana was located near the south pole and there were no continents at high northern latitudes. There would have been sea ice but the sedimentary evidence for glaciation is based on terrestrial and shallow marine continental margin sediments. There may have been a small ice sheet at high northern latitudes in the middle Permian in what is now northeast Siberia.

 

[Asbo Zaprudder]

Not for many tens of thousands of years if Milankovitch Theory is correct -- even if anthropogenic global warming is not taken into account.

http://en.wikipedia.org/wiki/Milankovitch_cycles

ETA: There is an alternative hypothesis based on the inclination of the Earth's orbit with respect to the ecliptic.

http://muller.lbl.gov/papers/sciencespectra.htm

http://muller.lbl.gov/papers/nature.html

This is apparently a better fit for the periodicity of ice ages over the past million years. It makes a similar prediction to MT for the likely onset of the next ice age.

 

[JustAFriend]

Everything cycles.

It's not a matter of IF but of WHEN.

 

[JiNX-01]

A slightly off-topic, but related matter:

I don't recall there ever being an ice age in the southern hemisphere. Anybody know if there has been and if not, why not?

Aside from today (Antarctica is completely ice-covered), both the Ordovician glaciation and the late Paleozoic ice age were centered in the southern hemisphere. In the late Paleozoic ice age, glaciation was widespread over South America, India, southern Africa, Australia, and Antarctica. In addition, two of the three late Precambrian "Snowball Earth" glaciations included ice in the southern hemisphere, but ice was basically global then anyway.

Thanks! It just always seemed that whenever I watch a documentary about an ice age, it's always about the one in North America (Europe and Asia neven even get a mention ).

 

[RoJoHen]

It always seemed that whenever I watch a documentary about an ice age, it's always about the one in North America (Europe and Asia neven even get a mention ).

That's because our ice ages are way better than the other ice ages.

 

[JiNX-01]

It always seemed that whenever I watch a documentary about an ice age, it's always about the one in North America (Europe and Asia neven even get a mention ).

That's because our ice ages are way better than the other ice ages.

Guess we can thank ILM for that.