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Scientific personnel
Team Members at University of Alaska Fairbanks: V. E. Romanovsky,
K. Yoshikawa (Water and Environmental Research Center, UAF, Alaska),
S. S. Marchenko, G. S. Tipenko, A.D. McGuire (Alaska Cooperative
Fish and Wildlife Research Unit, UAF), Nicole Mölders, Igor
Semiletov, Natalia Shakhova (IARC, UAF, Alaska).
Partner Organizations: Stevens Inst. of Technology, New
Jersey (N. Panikov), University of Kansas (P. Gogineni), International
Permafrost Association (J. Brown).
Collaborators: J. Christensen (Danish Meteorological Institute),
H.- W. Hubberten (Alfred Wegener Institute, Potsdam, Germany)

Research and Education
This project is a logical continuation of our
last project to record and archive the data on active layer
and permafrost dynamics at our sites within Alaska. The data we
collected from these sites during the previous field season. Quality
control was also performed and data were converted in a standard
format for the submission to JOSS
and to NSIDC
for archiving. We are contributing material to the IARC
web site describing CAMP.
The work on transfer the knowledge gained in permafrost
dynamics research into the development and implementation of an
evaluated soil-freezing/thawing module in CCSM was continued. We
worked together with N. Mölders group on comparison between
modeling results from the CCSM and our site-specific models. Input
data and results of site-specific comprehensive permafrost modeling
from the "cold permafrost" site (Barrow) prepared and compared with
the results of application of a coupled GCM. We prepared data for
comparison at two additional sites ("warm permafrost" and "no permafrost")
from the Seward Peninsula. We are also preparing necessary input
data for spatially distributed permafrost model GIPL
for the entire Alaska. First version of a new spatially distributed
permafrost model for Alaska was developed and results were delivered
at the Fall AGU meeting
in San Francisco in two presentations, one of which was an
invited presentation. We continued the work on interpretation of
CH4 measurements in thermokarst lakes and
lakes of other origin in the Fairbanks area and along the Alaskan
transect (so far - south from Fairbanks).
We organized and conducted the Workshop on Spatially
Distributed Modeling and Remote Sensing of Permafrost/Frozen Ground
that was held in IARC, University of Alaska Fairbanks in October
17-20, 2004. Workshop was sponsored by International
Arctic Research Center (IARC), University of Alaska Fairbanks,
Office of Polar Programs, National Science Foundation USA, NASA,
Climate and Cryosphere Program (CliC), World Meteorological Organization,
and International Permafrost Association (IPA). 31 scientists from
11 countries (Canada - 3, China - 1, Denmark -2, France - 1, Germany
- 2, Japan - 1, Kazkhstan - 1, Mongolia - 1, Norway - 1, Russia
- 3, USA - 15) participated in this workshop. 30 presentations were
made during the workshop.

Permafrost observatories
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"Chandalar
shelf" site
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"Fox"
site
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"Franklin
Bluffs" site
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Thermal state of permafrost in Alaska
A comprehensive system of permafrost observatories
was established in the late 1970s and early 1980s by the Geophysical
Institute, University of Alaska Fairbanks along the Trans-Alaska
Pipeline and at other locations in Alaska (Osterkamp, 1983;
Osterkamp, 2003; Osterkamp and Romanovsky, 1999). Depths of
these boreholes are typically 60 to 80 meters and measurements
are usually taken annually. Many of these observatories are
also equipped with shallow (down to 1 meter) cables for temperature
measurements and soil moisture sensors.
During the last 20 years, permafrost temperatures
in Alaska have been changing noticeably. Generally, an increase
in permafrost temperatures in Alaska during the last two decades
was more pronounced at the coastal Arctic sites (from 1.5
to 3.0°C at the permafrost table) and less pronounced in the
Interior Alaska (from 0.5 to 1.5°C).
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"Deadhorse"
site
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"Galbraith
Lake" site
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"Happy
Valley" site
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"Old
Man" site
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"West
Dock" site
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"Yukon
Bridge" site
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Click on each graph to see full size image
(20 - 40 kb)
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Major findings from these activities
Together with N. Mölders group, we found fairly
good agreement between our temperature measurements and modeling
at the Barrow site with modeled soil temperatures when properly
parameterized soil temperature module of a GCM was used. We continue
to investigate the sources of the modeled results deviation from
measured data.
Development of principal and other disciplines
This research should make important contributions to Arctic System
Science as it offers a mechanism by which field-based and modeling
research in both climatology and permafrost geophysics can be synthesized
in the context of modeling the Arctic System. We believe that the
study we are conducting will help articulate future research directions
for representing the role of high latitude terrestrial ecosystems
in the Arctic System.

GIPL 2.0 - Spatially Distributed Model of Permafrost
Dynamics in Alaska
Given the possibility of climate warming in
the near future, an evaluation of the magnitude of changes
in the ground thermal regime becomes desirable for assessments
of possible ecosystem responses and impacts on infrastructure
in the Arctic and sub-Arctic regions. In the past,
a soil model GIPL 1.0 developed at the Geophysical Institute
Permafrost Lab was used to simulate the dynamics of the active
layer thickness and mean annual ground temperature, both retrospectively
and prognostically, using climate forcing from Global Climate
Models.
The GIPL 1.0 model is a quasi-transitional, spatially
distributed, analytical model for the active layer thickness
and mean annual ground temperature. This model is incorporated
into GIS, which contains the information on geology, soils
properties, vegetation, and snow distribution.
GIS allows visualization of input and output parameters and
their representation in the form of digital maps. As a further
significant step in the GIPL model development, we replaced
the analytical solution with a numerical model based on a
finite difference method for the non-linear Heat Conduction
Equation.
In this model the process of soil freezing/thawing
is occurring in accordance with the unfrozen water content
curve, which is specific for each soil layer and for each
geographical location. For each grid point on the map we used
a one-dimensional multi-layer model of soil down to the depth
of a constant geothermal heat flux (typically 500 to 1000
m). At the upper boundary, there are insulating layers of
snow and vegetation that can change their properties with
time. Special Enthalpy formulation of the energy conservation
law makes it possible to use a coarse vertical resolution
without loss of latent heat effects in phase transition zone
even in case of fast temporally and spatially varying temperature
fields. The new version of GIPL (GIPL 2.0) calculates soil
temperature and liquid water content fields for the entire
spatial domain with daily, monthly and yearly resolutions.
The merge of the new GIPL and the GIS technique provides a
unique opportunity to analyze spatial features of permafrost
dynamics with high temporal resolution.
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