BOREAS HYD-03 Snow Measurements

Summary

The BOREAS HYD-03 team collected several data sets related to the hydrology of 
forested areas. This data set contains measurements of snow depth, snow density 
in 3-cm intervals, an integrated snow pack density and snow water equivalent 
(SWE), and snow pack physical properties from snow pit evaluation taken in 1994 
and 1996.  The data were collected from several sites in both the SSA and the 
NSA.  A variety of standard tools were used to measure the snowpack properties, 
including a meter stick (snow depth), a 100 cc snow density cutter, a dial stem 
thermometer and the Canadian snow sampler as used by HYD-04 to obtain a snow 
pack-integrated measure of SWE. This study was undertaken to predict spatial 
distributions of snow properties important to the hydrology, remote sensing 
signatures, and the transmissivity of gases through the snow.  The data are 
available in tabular ASCII files.

Table of Contents

   *  1 Data Set Overview
   *  2 Investigator(s)
   *  3 Theory of Measurements
   *  4 Equipment
   *  5 Data Acquisition Methods
   *  6 Observations
   *  7 Data Description
   *  8 Data Organization
   *  9 Data Manipulations
   *  10 Errors
   *  11 Notes
   *  12 Application of the Data Set
   *  13 Future Modifications and Plans
   *  14 Software
   *  15 Data Access
   *  16 Output Products and Availability
   *  17 References
   *  18 Glossary of Terms
   *  19 List of Acronyms
   *  20 Document Information

1. Data Set Overview

1.1 Data Set Identification

BOREAS HYD-03 Snow Measurements

1.2 Data Set Introduction

The data pertaining to this documentation include all snow-related
measurements made during the field campaigns.  These measurements include
snow depth and density in 3-cm intervals and integrated throughout the
snow pack as well as snow temperatures. The data were collected from several 
sites in both the BOReal Ecosystem-Atmosphere Study (BOREAS) Southern Study Area 
(SSA) and the Northern Study Area (NSA).  A variety of standard tools were used 
to measure the snow pack properties including a meter stick (snow depth), a 
100-cc snow density cutter, a dial stem thermometer, and the Canadian snow 
sampler as used by HYD-04 to obtain a snow pack-integrated measure of snow water 
equivalent (SWE).

1.3 Objective/Purpose

This study was undertaken to predict spatial distributions of snow properties 
important to the hydrology, remote sensing signatures, and the transmissivity of 
gases through the snow.

1.4 Summary of Parameters

Parameters measured with respect to this documentation are snow depth 
variability and snow density specific to land cover types at the flux tower 
sites visited.  These data allow the calculation of SWE.  Additional parameters 
measured include snow pack temperatures.

1.5 Discussion

This study was conducted under the hypothesis that energy transfer and SWE would 
vary spatially as a function of both the canopy closure and the distance from 
tree stems. Therefore, to obtain an accurate spatial average, random locations 
were measured irrespective of the location of trees. The representativeness of 
the snow depths to the site depends partially on the number of measurements. Raw 
measurements of snow depths near tree stems and under different canopy closures 
are available from the Principal Investigator (PI).  Certain snow metamorphic 
processes are driven by snow pack temperature gradients and an effort was made 
to measure that variable in the boreal forests.

1.6 Related Data Sets

BOREAS HYD-04 Standard Snow Course Data
BOREAS HYD-04 Areal Snow Course Data

2. Investigator(s)

2.1 Investigator(s) Name and Title

Robert E. Davis
Research Physical Scientist
U.S. Army Cold Regions Research and Engineering Laboratory (CRREL)

2.2 Title of Investigation

Distributed Energy Transfer Modeling in Snow and Soil for Boreal Ecosystems

2.3 Contact Information

Contact 1:
----------------
Janet P. Hardy          
U.S. Army CRREL           
Hanover, NH              
(603) 646-4306          
(603) 646-4397 (fax)         
jhardy@.crrel.usace.army.mil

Contact 2:
----------------
Dr. Robert E. Davis       
U.S. Army CRREL             
Hanover, NH                 
(603) 646-4219            
(603) 646-4397 (fax)           
bert@crrel.usace.army.mil 

Contact 3:
----------------
David Knapp
NASA GSFC
Greenbelt, MD 
(301) 286-1424
(301) 286-0239 (fax)
David.Knapp@gsfc.nasa.gov

3. Theory of Measurements

Several random snow depth measurements were made over the area around each site 
to assess the variability of snow depth.   At one or more locations in the 
forest, snow pits were dug and profiles of the snow density and temperature were 
included in the measurements.  The snow density profiles were used to calculate 
an average snow pack density to test the assumption that average density was 
more conservative than depth.  This assumption proved valid; thus measurements 
of snow depth, in conjunction with average snow pack density, provide accurate 
estimates of SWE. SWE is the vertical depth of water that would be obtained by 
melting the snow.

Snow temperature measurements were made in part to initialize the snow
process model as well as to provide important information for estimating the 
timing of snow ablation.

4. Equipment

4.1 Sensor/Instrument Description

Centimeter scale (meter stick) - for snow depth measurements.

100-cc snow density cutter - allows weight measurement of 100-cc volume of snow, 
from which the snow density is determined.  The dimensions of the cutter are 3 
cm x 5.5 cm x 6 cm.  This technique measures snow density at intervals of 3 cm 
height.

Electronic top loader balance - provides weight of snow, which allows 
determination of snow densities accurate within 5% (cutter and scale together).

Canadian snow sampler -  measures snow depth and provides data on an integrated 
snow density and SWE. 

4.1.1 Collection Environment

All data were collected during winter environments.  The equipment used is
designed for winter use, so the collection environment was
appropriate for these measurements.

4.1.2 Source/Platform

Ground.

4.1.3 Source/Platform Mission Objectives

This work was undertaken at several sites within the BOREAS modeling area
to obtain a better understanding of the variations of snow depth and density in
different land cover types.

4.1.4 Key Variables

snow depth
snow pack density
SWE
snow temperature

4.1.5 Principles of Operation

The centimeter scale is inserted into the snow pack, and the depth of the snow 
is read from the scale.  For snow density, a known volume of snow is weighed and 
its volume density is then determined from the formula in Section 9.1.  Two 
different techniques were used to determine snow density.  One used the 100-cc 
snow cutter, and the other used the Canadian snow sampler.  

Snow temperatures are read from a horizontally inserted thermometer.

4.1.6 Sensor/Instrument Measurement Geometry

Not applicable.

4.1.7 Manufacturer of Sensor/Instrument

Snow density cutter:
SNOWMETRICS
Box  52
Wilson, WY  83014
(307) 739-9458

Electronic balance:
ACCULAB
8 Pheasant Run
Newtown, PA  18940
(215) 579-3170

Canadian snow sampler:

(No manufacturers address was given)
1-Eastern Snow Conference (ESC)-30 snow sampler
1-spring balance for ESC-30
1-cradle
1-measuring stick/ruler (cm).

Thermometer:
Cole - Palmer Instrument Co.
7425 North Oak Park Ave.
Niles, IL  60714-9930

4.2 Calibration

The electronic balance was calibrated using a 200-gram calibration weight.

Thermometers were calibrated using the ice bath calibration method.  This
method involves placing the temperature sensors in a well mixed combination
of water and ice, which will have a known temperature of 0 C.  Thermometers
are then adjusted as close as possible to 0 C while in the ice bath.

4.2.1 Specifications

Not available.

4.2.1.1 Tolerance

Electronic balance:

Accuracy is within 5% when used in conjunction with snow density cutter (+/- 0.1 
g when used alone).

Thermometer:
Range:  -50 C to 150 C
+/- 0.8% full-scale precision or +/- 1.5 C
Resolution = 0.1 C

4.2.2 Frequency of Calibration

Prior to field use.

4.2.3 Other Calibration Information

Not available.

5. Data Acquisition Methods

100-cc Snow Cutter:

Snow depth measurements were made with a centimeter scale by walking through the 
area taking random depth measurements.  A zero snow depth occurred when the 
measurement landed at a tree stem.  For the snow density profiles, a 
representative area was chosen, a vertical exposure of the snow pack was exposed 
to the north, and snow density measurements were made with the 100cc snow cutter 
every 3 vertical cm until the entire snow pack was measured (i.e. a 45 cm deep 
snow pack would require 15 measurements of snow density to obtain the snow pack 
density profile).

Canadian Snow Sampler:

The Canadian snow sampler is used by inserting the tube through the snow
pack to the soil, twisting the tube, and removing the tube and snow core.
The tube and snow core are weighted using the spring scale, and the snow
depth is read from the centimeter scale on the tube.

Snow Temperature:
 
Snow temperature measurements are made by inserting the thermometer
horizontally into the snow pit at 10-cm height intervals.  Temperatures are
read directly off the thermometer dial to the nearest degree once the
thermometer has stabilized.

6. Observations

6.1 Data Notes

None.

6.2 Field Notes

None.

7. Data Description

7.1 Spatial Characteristics

7.1.1 Spatial Coverage

Point measurements were scattered over a 1-hectare area within 50 meters of the 
flux tower, if it was near a flux tower site.  The following coordinates are 
approximate and based on the North American Datum of 1983 (NAD83).

SWE:

SITE_ID                    LONGITUDE   LATITUDE
------------------------- ---------- ----------
SSA-OBS-HYD03-HYD03-SWE01 -105.11779   53.98717
SSA-AGR-HYD03-HYD03-SWE01 -104.78041   53.57649
NSA-OJP-FLXTR-HYD03-SWE01  -98.62028   55.93011
NSA-9BS-HYD3A-HYD03-SWE01  -97.89026   55.81011
NSA-YBS-HYD03-HYD03-SWE01  -97.87026   55.83011
NSA-MIX-HYD03-HYD03-SWE01  -97.84025   55.85011
NSA-9BS-HYD3B-HYD03-SWE01  -97.82025   55.87011
NSA-YJP-FLXTR-HYD03-SWE01  -98.29027   55.90011
SSA-MIX-110B1-HYD03-SWE01 -105.82606   54.58848
SSA-999-110C1-HYD03-SWE01 -105.82461   54.57386
SSA-ASP-110E1-HYD03-SWE01 -105.81461   54.54696
SSA-BSH-110G1-HYD03-SWE01 -105.81221   54.52526
SSA-ASP-110H1-HYD03-SWE01  -105.8067   54.50956
SSA-BRN-110J1-HYD03-SWE01  -105.8123   54.48146
SSA-ASP-110K1-HYD03-SWE01    -105.81   54.46696
SSA-CLR-110L1-HYD03-SWE01  -105.8024   54.43746
SSA-YJP-122D1-HYD03-SWE01 -104.61914   53.84426
SSA-999-122E1-HYD03-SWE01 -104.61944   53.84916
SSA-MIX-122F1-HYD03-SWE01 -104.62214   53.85586
SSA-MIX-122G1-HYD03-SWE01 -104.60623   53.89836
SSA-999-WSK01-HYD03-SWE01  -106.0705   53.94005
SSA-9OA-FLXTR-HYD03-SWE01 -106.19051   53.63005
NSA-OBS-FLXTR-HYD03-SWE01  -98.48027    55.8801
SSA-OJP-HYD03-HYD03-SWE01 -104.69044   53.92006
SSA-9PR-HYD03-HYD03-SWE01 -105.27048   53.56005
  
Snow Depth Sites:

SITE_ID                    LONGITUDE   LATITUDE
------------------------- ---------- ----------
SSA-OJP-FLXTR-HYD03-SDP01 -104.69203   53.91634
SSA-AGR-HYD03-HYD03-SDP01 -104.78041   53.57649
SSA-WAT-FLXTR-HYD03-SDP01 -106.04122   53.83105
SSA-9OA-FLXTR-HYD03-SDP01 -106.19779   53.62889
SSA-OBS-FLXTR-HYD03-SDP01 -105.11779   53.98717

Snow Pits:

SITE_ID                    LONGITUDE   LATITUDE
------------------------- ---------- ----------
SSA-AGR-HYD03-HYD03-SPT01 -104.78041   53.57649
SSA-WAT-FLXTR-HYD03-SPT01 -106.04122   53.83105
SSA-9OA-FLXTR-HYD03-SPT01 -106.19779   53.62889
SSA-OBS-FLXTR-HYD03-SPT01 -105.11779   53.98717
SSA-999-WSK04-HYD03-SPT01 -106.09068    53.9232
SSA-OJP-FLXTR-HYD03-SPT01 -104.69203   53.91634

Snow Temperature:

SITE_ID                    LONGITUDE   LATITUDE
------------------------- ---------- ----------
NSA-9BS-HYD3B-HYD03-SHT06  -97.82025   55.87011
NSA-9BS-HYD3A-HYD03-SHT01  -97.89026   55.81011
NSA-9BS-HYD3A-HYD03-SHT02  -97.89026   55.81011
NSA-YBS-HYD03-HYD03-SHT03  -97.87026   55.83011
NSA-MIX-HYD03-HYD03-SHT04  -97.84025   55.85011
NSA-9BS-HYD3B-HYD03-SHT05  -97.82025   55.87011
NSA-YJP-FLXTR-HYD03-SHT01  -98.29027   55.90011
NSA-OJP-FLXTR-HYD03-SHT01  -98.62028   55.93011
NSA-OBS-FLXTR-HYD03-SHT01  -98.48027    55.8801
SSA-9PR-HYD03-HYD03-SHT01 -105.27048   53.56005

Subcanopy Meteorological:

SITE_ID                    LONGITUDE   LATITUDE
------------------------- ---------- ----------
SSA-OBS-FLXTR-HYD03-SCM01 -105.11779   53.98717
SSA-OJP-FLXTR-HYD03-SCM01 -104.69203   53.91634
SSA-9OA-FLXTR-HYD03-SCM01 -106.19779   53.62889

Subcanopy Radiation:

SITE_ID                    LONGITUDE   LATITUDE
------------------------- ---------- ----------
SSA-OBS-FLXTR-HYD03-SCR01 -105.11779   53.98717
SSA-9OA-FLXTR-HYD03-SCR01 -106.19779   53.62889
SSA-OJP-FLXTR-HYD03-SCR01 -104.69203   53.91634

7.1.2 Spatial Coverage Map

Not available.

7.1.3 Spatial Resolution

Point source data (snow pits).

7.1.4 Projection

The locations of these point sites are based on NAD83.

7.1.5 Grid Description

Not applicable.

7.2 Temporal Characteristics

7.2.1 Temporal Coverage

1994: Focused Field Campaign-Winter (FFC-W) (05-Feb-1994 to 15-Feb-1994) and 
FFC-Thaw (FFC-T) (17-Apr-1994 to 27-Apr-1994)
1996: FFC-W (29-Feb-1996 to 12-Mar-1996)

7.2.2 Temporal Coverage Map

05-Feb-1994	SSA-Prairie
06-Feb-1994	SSA-Old Jack Pine (OJP)
07-08-Feb-1994	SSA:  Transect near Montreal Lake (Gamma Calibration Lines)
09-Feb-1994	SSA-Waskesui Lake
10-Feb-1994	SSA-Old Aspen (OA)
13-Feb-1994	NSA:  near AYJP on Gilliam Road.
14-Feb-1994	NSA-Young Jack Pine (YJP)
15-Feb-1994	NSA-OJP

17-Apr-1994	NSA-YJP
18-Apr-1994	NSA-Old Black Spruce (OBS)
20-Apr-1994	NSA-OBS
22-Apr-1994	NSA-YJP
24-Apr-1994	NSA-YJP
24-Apr-1994	NSA-YJP
25-Apr-1994	NSA-OJP
26-Apr-1994	NSA-YJP
27-Apr-1994	NSA-OPEN

29-Feb-1996	SSA-OBS
01-Mar-1996	SSA-AG
02-Mar-1996 SSA-OBS
04-Mar-1996 SSA-OA
05-Mar-1996 SSA-OJP
07-Mar-1996 SSA-Namekus
11-Mar-1996 SSA-OJP
12-Mar-1996 SSA-Waskesui

7.2.3 Temporal Resolution

Snow depth, SWE: biweekly during FFC-W 1994, 3-5 days during FFC-T 1994, more 
frequently depending on weather.

Snow temperatures: FFC-W 1994 - 1-3 days (less for the upper portion of the snow 
pack).
FFC-T 1994 -  Once the snow pack is isothermal at 0 C during the thaw period,
the top portion of the snow pack may show some diurnal temperature
fluctuations, but otherwise the snow pack may remain at the melting point
until the snow is gone.

7.3 Data Characteristics

Data characteristics are defined in the companion data definition files 
(h03sd96d.def), (h03sp96d.def), (h03swed.def), (h3swe96d.def), and 
(h03sntmd.def).

7.4 Sample Data Record

Sample data format shown in the companion data definition files (h03sd96d.def), 
(h03sp96d.def), (h03swed.def),  (h3swe96d.def), and (h03sntmd.def).

8. Data Organization

8.1 Data Granularity

All of the Snow Measurement Data are contained in the following datasets:   
(h03sd96d.dat), (h03sp96d.dat), (h03swed.dat), (h3swe96d.dat), and 
(h03sntmd.dat).

8.2 Data Format(s)

The data files contain numerical and character fields of varying length 
separated by commas. The character fields are enclosed with  a single apostrophe 
marks. There are no spaces between the fields.  Sample data records are shown in 
the companion data definition files (h03sd96d.def), (h03sp96d.def), 
(h03swed.def), (h3swe96d.def), and (h03sntmd.def).
 
9. Data Manipulations

9.1 Formulae

To determine snow pack SWE:

Snow depth (mm) x [snow density (kg/m3)/1000] = SWE (mm)

9.1.1 Derivation Techniques and Algorithms

Not applicable.

9.2 Data Processing Sequence

9.2.1 Processing Steps

For snow density and snow water equivalence:

1).  Determine mean snow depth at site.
2).  Determine mean snow pack density at site (if more than one snow pack 
density measurement exists at any site then average the means).
3).  Use formula above to calculate SWE.

9.2.2 Processing Changes

None.

9.3 Calculations

9.3.1 Special Corrections/Adjustments

None.

9.3.2 Calculated Variables

None.

9.4 Graphs and Plots

None.

10. Errors

10.1 Sources of Error

1.  In measuring snow depth, the probe may at times hit a fallen branch or 
understory and underestimate snow depth at that point.

2.  Snow pack density data were often derived from a single snow pit evaluation.  
Error would be reduced if it was practical to obtain several measurements of 
mean snow pack density.

3.  An unresolved, systematic discrepancy exists between the determination of 
snow water equivalence using the Canadian Snow Sampler and the technique using 
mean snow depths and mean snow pack density determined from the 100 cc density 
cutter.

10.2 Quality Assessment

10.2.1 Data Validation by Source

Comparison was attempted with HYD-04 snow survey data.  Data were similar,
but time and location of data collection points were not the same and
therefore cannot be directly compared.

10.2.2 Confidence Level/Accuracy Judgment

The confidence in snow depth data is a function of the number of measurements 
made (n) at each site.  The more measurements made, the better the variability 
is represented and therefore the greater the confidence.

The snow temperature data are good indications of the temperature gradient
at that point.  The temperature gradient will vary with snow depth,
proximity to a tree, or snow pack base (i.e., forest floor, ice on pond).

10.2.3 Measurement Error for Parameters

Snow density measurement accuracy = 5%.

10.2.4 Additional Quality Assessments

The data were doublechecked.  Calculations were performed at least twice, and 
more often if a discrepancy existed.

10.2.5 Data Verification by Data Center

These data were reviewed to make sure that data were loaded properly.

11. Notes

11.1 Limitations of the Data

Snow depth and density and temperatures can be highly variable in forested
environments.  A single data point cannot accurately represent a forest
snow pack.   Also, during periods of thaw, the snow pack changes rapidly, and
a measurement made on one day may not have much bearing on the snow pack
the next day.  Note that on 09-Mar-1996 the daily high air temperature
reached 0 C and stayed above freezing for most of the remainder of the
field campaign.  During this period, the snow pack changed rapidly.

11.2 Known Problems with the Data

An unresolved, systematic discrepancy exists between the determination of snow 
water equivalence using the Canadian Snow Sampler and the technique using mean 
snow depths and mean snow pack density determined from the 100 cc density 
cutter.

11.3 Usage Guidance

See Section 11.1.

11.4 Other Relevant Information

Canadian snow samplers are brittle when very cold, as Piers Sellers found out.

12. Application of the Data Set

This data set could be used for a quantitative analysis to compare SWE
among different land cover types.  The data are also useful for snow
modeling purposes or estimating the water potentially available to the soil
systems.

13. Future Modifications and Plans

None.

14. Software

14.1 Software Description

An undetermined spreadsheet software program was used to organize the data.

14.2 Software Access

None given.

15. Data Access (This section for BORIS and ORNL DAAC Use)

Primary contact:

Ms. Beth Nelson
BOREAS Data Manager
NASA GSFC
Greenbelt, MD
(301) 286-4005
(301) 286-0239 (fax)
beth@ltpmail.gsfc.nasa.gov

15.2 Data Center Identification

See Section 15.1.

15.3 Procedures for Obtaining Data

Users may place requests by telephone, electronic mail, or fax.

15.4 Data Center Status/Plans

The HYD-03 snow measurement data are available from the Earth Observing System 
Data and Information System (EOSDIS) Oak Ridge National Laboratory (ORNL) 
Distributed Active Archive Center (DAAC).
The BOREAS contact at ORNL is:

ORNL DAAC User Services
Oak Ridge National Laboratory
(865) 241-3952
ornldaac@ornl.gov
ornl@eos.nasa.gov

16. Output Products and Availability

16.1 Tape Products

Contact BORIS staff.

16.2 Film Products

Contact BORIS staff.

16.3 Other Products

Contact BORIS staff.

17. References

17.1 Platform/Sensor/Instrument/Data Processing Documentation

Not applicable.

17.2 Journal Articles and Study Reports

Davis, R.E., C. Woodcock, and J.P. Hardy. 1996. Toward spatially distributed 
modeling of snow in the boreal forest.  Eos Transactions, AGU 1995 Fall Meeting, 
Abstract, p. 218.

Davis, R.E., J.P. Hardy, W. Ni, C. Woodcock, C.J. McKenzie, R. Jordan, and
X. Li. 1997.  Variation of snow ablation in the boreal forest: A sensitivity 
study on the effects of conifer canopy.  Journal of Geophysical Research. 
102(D24):29389-29396.

Hardy, J.P., R.E. Davis, and G.C. Winston. 1995.  Evolution of factors
affecting gas transmissivity of snow in the boreal forest.  In: Biogeochemistry 
of Seasonally Snow-Covered Catchments (ed. by K. Tonnessen, M.W. Williams, and 
M. Tranter)  (Proc. Boulder Symp., July 1995). IAHS publication no. 228, p. 51-
60.

Hardy, J.P., R.E. Davis, and R. Jordan. 1996. Snow melt modeling in the boreal
forest. Eos Transactions, AGU 1996 Fall Meeting, abstract, p. 196.

Hardy, J.P., R.E. Davis, and J.C. McKenzie. 1995.  Snow Distribution Around
Trees:  Incorporation of snow interception patterns into spatially distributed 
snow models.  Eos Transactions, AGU 1995 Fall Meeting, Abstract, p. 202.

Hardy, J.P., R.E. Davis, R. Jordan, X. Li, C. Woodcock, W. Ni, and J.C.
McKenzie. 1997.  Snow ablation modeling at the stand scale in a boreal
jack pine forest.  Journal of Geophysical Research. 102(D24): 29397-29406.

Sellers, P. and F. Hall. 1994. Boreal Ecosystem-Atmosphere Study: Experiment 
Plan. Version 1994-3.0, NASA BOREAS Report (EXPLAN 94). 

Sellers, P. and F. Hall. 1996. Boreal Ecosystem-Atmosphere Study: Experiment 
Plan. Version 1996-2.0, NASA BOREAS Report (EXPLAN 96). 

Sellers, P., F. Hall, and K.F. Huemmrich. 1996. Boreal Ecosystem-Atmosphere 
Study: 1994 Operations. NASA BOREAS Report (OPS DOC 94). 

Sellers, P., F. Hall, and K.F. Huemmrich. 1997. Boreal Ecosystem-Atmosphere 
Study: 1996 Operations. NASA BOREAS Report (OPS DOC 96). 

Sellers, P.J., F.G. Hall, R.D. Kelly, A. Black, D. Baldocchi, J. Berry, M. Ryan, 
K.J. Ranson, P.M. Crill, D.P. Lettenmaier, H. Margolis, J. Cihlar, J. Newcomer, 
D. Fitzjarrald, P.G. Jarvis, S.T. Gower, D. Halliwell, D. Williams, B. Goodison, 
D.E. Wickland, F.E. Guertin. 1997. BOREAS in 1997: Experiment overview, 
scientific results, and future directions. Journal of Geophysical Research. 
102(D24):28731-28770.

Sellers, P., F. Hall, H. Margolis, B. Kelly, D. Baldocchi, G. den Hartog, J. 
Cihlar, M.G. Ryan, B. Goodison, P. Crill, K.J. Ranson, D. Lettenmaier, and D.E. 
Wickland. 1995. The boreal ecosystem-atmosphere study (BOREAS): an overview and 
early results from the 1994 field year. Bulletin of the American Meteorological 
Society. 76(9):1549-1577. 

Winston, G.C., B.B. Stephens, E.T. Sundquist, J.P. Hardy, and R.E. Davis.
1995.  Seasonal variability in gas transport through snow in a boreal
forest.  In:  Biogeochemistry of Seasonally Snow-Covered Catchments (ed. by
K. Tonnessen, M.W. Williams, and M. Tranter)  (Proc. Boulder Symp., July
1995). IAHS publication no. 228, p. 61-70.

17.3 Archive/DBMS Usage Documentation

None.

18. Glossary of Terms

None.

19. List of Acronyms

ASCII   - American Standard Code for Information Interchange
BOREAS  - BOReal Ecosystem-Atmosphere Study
BORIS   - BOREAS Information System
cc      - cubic centimeters
CGR     - Certified by Group
CPI     - Certified by Principal Investigator
CPI-??? - CPI but questionable
CRREL   - Cold Regions Research Engineering Laboratory
DAAC    - Distributed Active Archive Center
EOS     - Earth Observing System
EOSDIS  - EOS Data and Information System
FFC-T   - Focused Field Campaign-Thaw
FFC-W   - Focused Field Campaign-Winter
GMT     - Greenwich Mean Time
GSFC    - Goddard Space Flight Center
HYD     - Hydrology
NAD83   - North American Datum of 1983
NASA    - National Aeronautics and Space Administration
NSA     - BOREAS Northern Study Area
OBS     - Old Black Spruce
OJP     - Old Jack Pine
ORNL    - Oak Ridge National Laboratory
PANP    - Prince Albert National Park
PI      - Principal Investigator
PRE     - Preliminary
SSA     - BOREAS Southern Study Area
SWE     - Snow Water Equivalent
URL     - Uniform Resource Locator
YBS     - Young Black Spruce
YJP     - Young Jack Pine

20. Document Information

20.1 Document Revision Date

     Written:    25-Mar-1997
     Revised:    20-Mar-1998

20.2 Document Review Date(s)

     BORIS Review:   12-Mar-1998
     Science Review: 15-Jul-1997 

20.3 Document ID

20.4 Citation

20.5 Document Curator

20.6 Document URL

Keywords

SNOW
SNOW WATER EQUIVALENT

HYD03_Snow_Meas.doc
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