12 August, 1997
Nevins Journal 08/12/97
Went out with soil scientists today to take samples in the active layer
and to try to cut cores in the permafrost for analysis of the pollen and
carbon content.
The team started out by cutting down to the frost at the
site and taking out blocks of moss and soil. (They used blocks so that
the sample site could be returned to as close to original condition as
possible.) The hole was cleaned out to the frost level at about 32 cm and
then the undisturbed wall was scraped so that layers would show.
Jim Bockheim worked in the open hole to identify and measure the soul
layers while Lynn Everett recorded the data and Wendy Eisner collected
material for the pollen analysis. The examination and photographing of
the soil layers took about an hour and then a complete set of samples of
known volumes was taken to enable an analysis of the materials that make
up the soil.
In lab the samples will be checked for carbon content, pH,cations,
and plant nutrient content. The carbon is of parcticular intrest
interest to the people on this part of the project because in many ofthe
of the global warming models the build up of carbon dioxide in the
atmosphere will cause a greenhouse effect. As the weather warms, more
permafrost thaws and more methane and carbon dioxide will be added to the
atmosphere which will in turn increase the warming and so on in a
repeating cycle. (This type of cycle is called a positive feedback loop.)
The start up or encouragement of a positive feed back loop is unstable
because it tends to cause change rather than stability.
The human body and the bodies of animals do not use positive feedback
loops to maintain homeostasis (balance ) in the body. Most body systems
use a negative feedback loop so as to avoid causing extreme swings on the
function of body systems. One of the few systems to use positive feedback
is the uterus at the time of delivery of a baby.
When we tried to drill into the permafrost, the drill would not start at
first. After about a half hour of working on the drill we finally got it
started but for some reason the drill would not turn .so we were unable to
extract our core sample. We did notice that the oil on the motor was low
on oil so when we got back to camp, they added oil and we hope that will
make the drill work.
Contact the TEA in the field at
.
If you cannot connect through your browser, copy the
TEA's e-mail address in the "To:" line of
your favorite e-mail package.
|