Searching on the net I found another NOAA site, but unless I missed it there is no link in the main NOAA site to this one. The site is the "National
Climatic Data Center on Abrupt Climate Change". This site has a lot of information about past abrupt climate changes and the possibility of having
one in the future.
This is what it says on the first page of that website.
" The paleoclimate record shows rapid and dramatic changes in climate have occurred in the past on global and regional scales. Here's what we know
and what we don't know about the causes and effects of these changes. "
" One of the best studied examples of abrupt change occurred as the Earth's climate was changing from a cold glacial to a warmer interglacial state.
During a brief period lasting about a century, temperatures in most of the Northern Hemisphere rapidly returned to near-glacial conditions, stayed
there for over 1,000 years in a time called the Younger Dryas (named after a small Arctic flower,) then about 11,500 years ago quickly warmed again.
In some places, the abrupt changes may have been as large as 10°C, and may have occurred over a decade.
There are times when the links don't want to load, you just have to keep on trying and will eventually get to them.
This is the part that is most interesting and that seems to warn us of what might be in the near future for us.
" Why did the thermohaline circulation change abruptly?
The Younger Dryas occurred during the transition from the last glacial period into the present interglacial (the Holocene). During this time, the
continental ice sheets were rapidly melting. A pulse of this meltwater flowing into the North Atlantic (Figure 8) reduced the salinity and density of
the surface ocean, causing a reduction in the rate of deepwater formation. As deepwater formation slowed, less warm water flowed north from the
tropics and the North Atlantic became colder. Eventually, the meltwater flux slowed and other changes occurred, causing deepwater formation to
" Recent Periods of Abrupt Climate Change
While smaller than abrupt changes during the last ice age, a number of abrupt shifts have been recorded since the glaciers receded. This post-glacial
period, known as the Holocene, covers the last 11,500 years. Some rapid changes have arrived as prolonged periods of drought, and have been
implicated in the collapse of early human civilizations.
This site seems to be there for anyone who is looking for the right information to find it, but it surely is not painting a very bright future if the
changes we are seeing nowadays are leading us to another abrupt climate change period like the ones we had in the past.
[edit on 12-6-2004 by Muaddib]