 The active
layer and permafrost are the primary subsurface components of the
Arctic land-atmosphere system. A permafrost research program is
proposed that combines field measurements, laboratory measurements,
and analyses and interpretations of data to be obtained at long-term
study sites along a transects. These sites are in undisturbed areas,
span a wide range of permafrost, climatic, and environmental conditions,
include drill holes in the permafrost (from 40 to 75 m in depth),
and have a long time series of data.
This research will focus on investigating how the
active layer and continuous permafrost, in a variety of climatic
and environmental settings, has responded and continues to respond
to climatic change.
Methods for regular and direct observations
of permafrost active layer parameters
Equipment
Temperature is measured by means of sensors “107
Temperature probe” (these sensors are made by company Campbell
Scientific Inc, or by means the MRC-probe, made by company MEASUREMENT
RESEARCH CORPORATION, or by means of sensors StowAway (XTI or Optic),
made by Onset
Computer Corporation.
The 107-sensors have to connect up to logger by rule:
purple wire – to AG, red wire – do voltage of measurement
(L or H), colorless wire – to G and black wire – in series
by three tags to E1 or E2.
The probes into MRC-rod manufactured after April 12th,
2001 have the color codes: red-power (+5 v), black-ground, blue-output
(analog out), orange-input (clock pulse).
The moisture of ground is measured by means of sensors
“Hydra Probe”. These sensors are made by company Stevens
Vitel Inc. You can make the acquaintance of the equipment with the
original Stevens
Vitel description.
The data are collected by CR10x measurement and control
module with AM416 Relay Multiplexer. You can make the acquaintance
of the equipment with the original Campbell
Scientific Inc. tutorial.
Before the measurements in the field you have to calibrate
all sensors “107 Temperature probe”. This operation means
putting the sensors into a thermos bottle with ice dust and measurement
of temperature. All sensors have to show a temperature of about
0°C; existing difference have to be taken into account during
future measurements with these sensors.
Objects in the field
Any measurements are described with metadata.
Metadata
(sample) (RTF-file, 9 kb)
Description of sites
For every site one must observe the thickness of snow-cover
(along the profiles and over the logger), the thickness of active
layer (at points of the regular 1m-grid), the weather (sun, clouds,
wind, temperature of air). No long walks over the sensors! It is
advisable to describe the landscape situation around the site (surface,
shapes of snow-forms, activity of exogenous processes – especially
cryogenic processes).
Operational procedure in the field (measurements
and data storage)
Your need to collect measured data into computer by
special program PC208E
No AC power-lines in the area of measurement!
Data processing
Temperature
One ought to accumulate results of measurements in Excel-Spreadsheet
with file-name in format: <NN>_d<YYYY>.xls; NN –
this is the first letters of borehole site (for example, DH=Deadhorse),
YYYY – this is the years of measurement (for example, 9700=1997-2000).
The measurements of temperature have to be corrected following the
results of calibration data getting-up the result - see
the sample. The results are processed and formatted in agreement
with Joss
standards and can be accessed in Joss
strorage.
Moisture
First step: You begin to processing the field data about
moisture of ground in different depths by transportation of initial
file *.dat – to Excel-spreadsheet. Every Vitel (sensor) give
4 voltages (measurement). The field equipment checks every voltage
against all sensors. For example, the voltage #1 check against the
Vitel 1, after them – against Vitel 2, after them – against
Vitel 3, and so forth) – see
the spreadsheet.
However, We must to transform this order for win the result. We
realize the data processing with the aid of computer special DOS-routine.
This program gives back the result parameters – including the
volumetric content of water, or the moisture of ground (“WATER”).
The input-file for this program has to contain the number matrix
in format “Text (tab delimited)” - with 6 columns (see
columns from E to J in the below spreadsheet). The program asks
we about A-probe. We must to answer “No” for the old sensors
and “Yes” for the new sensors. After them we receive the
output file for import him in result Excel – spreadsheet.
 
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