3 ms·

Well, the finds range from 9000 years to 1200 years old, so that not only suggests these areas might have been previously habitable as recently as 1200 years bu

Well, the finds range from 9000 years to 1200 years old, so that not only suggests these areas might have been previously habitable as recently as 1200 years but also that these areas were habitable for almost 10,000 years before becoming uninhabitable. Could it suggest a cyclic pattern? And, perhaps we are acting as catalysts to climate change with our greenhouse gas emissions?

Dewie 12y ago
> Could it suggest a cyclic pattern? We already know that we are currently in an ice age that goes through cycles of glacial periods (such as the colloquially named "last ice age") where a lot of North America, Europe and Siberia are covered in ice sheets; and warmer interglacial periods, such as this one, where the poles are covered by ice sheets (and also Greenland and various glaciers, and at high altitudes). Outside of ice ages (which is more common for Earth, when considering its whole history), the poles aren't covered by ice sheets. > And, perhaps we are acting as catalysts to climate change with our greenhouse gas emissions? Perhaps. And if so, whether that is for the better or for the worse in the grand scheme of things is yet to be seen; geologists say that we are "due" for another glacial period, based on previous glacial and interglacial periods. But human emission of CO2 could keep things from spiraling towards a cool down, which might delay the next glacial period for a long time. Or perhaps glacial periods are mostly caused by cosmological forces, which are out of our control; there doesn't seem to be any clear answers.
- Intermernet 12y ago
  There's also a theory that a period of non-standard warming at the beginning of a glaciation period will possibly cause a faster eventual cooling, and possibly a more severe glaciation, especially in Europe. Mostly due to altered ocean currents such as the "Great Ocean Conveyor". Pretty sure this has been modelled, but it's still being debated. http://science.nasa.gov/science-news/science-at-nasa/2004/05mar_arctic/ http://science.nasa.gov/science-news/science-at-nasa/2004/05... http://en.wikipedia.org/wiki/Thermohaline_circulation#Effects_on_global_climate http://en.wikipedia.org/wiki/Thermohaline_circulation#Effect...

Dewie 12y ago

> Could it suggest a cyclic pattern? We already know that we are currently in an ice age that goes through cycles of glacial periods (such as the colloquially named "last ice age") where a lot of North America, Europe and Siberia are covered in ice sheets; and warmer interglacial periods, such as this one, where the poles are covered by ice sheets (and also Greenland and various glaciers, and at high altitudes). Outside of ice ages (which is more common for Earth, when considering its whole history), the poles aren't covered by ice sheets. > And, perhaps we are acting as catalysts to climate change with our greenhouse gas emissions? Perhaps. And if so, whether that is for the better or for the worse in the grand scheme of things is yet to be seen; geologists say that we are "due" for another glacial period, based on previous glacial and interglacial periods. But human emission of CO2 could keep things from spiraling towards a cool down, which might delay the next glacial period for a long time. Or perhaps glacial periods are mostly caused by cosmological forces, which are out of our control; there doesn't seem to be any clear answers.

Intermernet 12y ago
There's also a theory that a period of non-standard warming at the beginning of a glaciation period will possibly cause a faster eventual cooling, and possibly a more severe glaciation, especially in Europe. Mostly due to altered ocean currents such as the "Great Ocean Conveyor". Pretty sure this has been modelled, but it's still being debated. http://science.nasa.gov/science-news/science-at-nasa/2004/05mar_arctic/ http://science.nasa.gov/science-news/science-at-nasa/2004/05... http://en.wikipedia.org/wiki/Thermohaline_circulation#Effects_on_global_climate http://en.wikipedia.org/wiki/Thermohaline_circulation#Effect...