Re: Sailing round Greenland?



Daryl Krupa, for prd <icycalmca@xxxxxxxxx > wrote:

Erik Hammerstad <egeha.is.all.you.need@xxxxxxxx > wrote:
<snip>
The book does not give a definite reference for its Camp Century
curve, possibly it's from a 1993 paper in Nature by Dansgaard
et.al. which is unavailable to me.

Erik:
That Nature article is not the primary source;
there are technical reports that carry the original data from
cores and boreholes.

I have found two other Camp
Century charts on the net,
http://www.aip.org/history/climate/xCampCent.htm and fig 6.2 from
Willi Dansgaard's book "Frozen Annals" ISBN: 87-990078-0-0,
available on line at http://www.nbi.ku.dk/side59440.htm. The
charts are not the same, allthough they agree in general.

Peter Alaca wrote:
Thanks Erik, also for your other post. The book sounds interesting.

Yes, Thank you also from me, Erik.

On the NorthGRIP site a lot of data (and articles and abstracts,
but not Dansgaard 1993) are available.
http://www.gfy.ku.dk/~www-glac/ngrip/index_eng.htm
You can draw your own curves.
<snip>

Thanks for that, too, Peter.

Details about the temperature history are lost as
we go back in time. The curves become more and
more average curves. The abrupt and violent
climate changes at the time of the termination of
the last ice age between
13000 and 9000 years BC
(15000 and 11000 years BP) are thus completely
erased. T
<snip>

Peter, it is not good practice to simply
add 2000 to dates BC to get dates BP.
You should either add 1950 years, or
only use "BP" for radiocarbon dates, which is its original use.
Dates "BP" are not 2000 0r 1950 years before dates "BC", because
radiocarbon dating must be correlated to other dating methods,
to allow for differences in the original abundance of
the material whose decay is being measured in radiocarbon dating.

If your dates were originally "BP", then the dates "BC" you give are
wrong, and vice versa.
Which was the orignal version, please?

- Daryl Krupa

It is a quote, including the conversion (see the quotationmarks
and the file).
And I think it are real years, not radiocarbon years, but I may
be wrong because I don't realy understand how they obtain
the temperatures.

--
p.a.

.