ERTS-1 imagery for mapping and detecting changes in snow cover on land and glacier

Meier, M. F.

English

NASA Technical Reports Server

Paper W 19 
EVALUATE ERTS IMAGERY FOR MAPPING AND DETECTION OF CHANGES OF 
SNOWCOVER ON LAND AND ON GLACIERS 
Mark F. Meier, U. S GeoIogicdl Suruey, Tacoma, Washington 
The percentage of snowcover area on specific drainage basins was measured from ERTS 
imagery with the Stanford Research Institute console. Basin outlines were electronically 
superimposed on 'magry. and video density slicing used to measure areas. For a basin with 
22.6 percent snowcover, results were repeatable to within 4 percent of the snowovered 
area. Data from f ive ERTS and U-2 images of the melt seascn snowcover in the Thunder 
Creek drainage basin in the Xorth Cascade Range were combined with existing hydrologic 
and meteorologk observations to enable caiculation of the space and time distribution of the 
water stored in this mountain snowpack. Knowledge gained frorn this model can then be 
used in subsequent years to forecast meltwater runoff during the critical late summer period. 
Similar data could be used for frequent updating of expected inflow to reservoirs if similar 
satellite data were available in the future. 
Snow-covered area and snowline altitudes were also determined by enlarging ERTS 
imagery to 1 :250,000 and using a transparent map overlay. Under favorable conditions, 
showline altitude was determined to an accuracy of about 60pm. Ability to map snowcover 
or to detemrine snowline altitude depends primarily on cloud cover and vegetation and 
secondarily on slope, terrain roughness, sun angle, radiometric fidelity, and amount of 
spectral informa5on available. 
Clacier accumulation area ratios were determined from ERTS imagery. Also, subtle 
flow structures, undetected on aerial photographs, were visible. Surging glaciers were iden- 
tified, and the changes resulting from the surge of a large glacier were measured. Marked 
chsnges in tidal glacier termini were discovered between successive ERTS passes. 
https://ntrs.nasa.gov/search.jsp?R=19730008755 2020-03-17T08:00:05+00:00Z


Evaluate ERTS Imagery for Mapping and Detection of Changes of Snowcover on Land and on Glaciers

There are no author-identified significant results in this report

E 7. 4 - 1 0. 0.02.
wiL6 imaNlde idnrar iAR spffri C . S
in the interest of early and wide dis-
semination of Earth Resources Survey
Program information and without liability
for any use made thereof."
EVALUATE ERTS IMAGERY FOR MAPPING AND DETECTION OF CHANGES
OF SNOWCOVER ON LAND AND ON GLACIERS
Mark F. Meier
U.S. Geological Survey
Tacoma, Washington 98402
31 August 1973
Type 1 Progress Report for Period 1 July 1973 - 31 August 1973
E74-10002) EVALUATE ERTS IMAGERY FOR N74-11143
MAPPING AND DETECTION OF CHANGES OF
SNOWCOVER ON LAND AND ON GLACIERS
Progress Report, 1 Jul, - 31 (Geological Unclas
Survey) 4 p HC $3.00 CSCL 08B G3/13 00002
Prepared for:
Goddard Space Flight Center
Greenbelt, Maryland 20771
https://ntrs.nasa.gov/search.jsp?R=19740003030 2020-03-23T14:05:27+00:00Z
TYPE 1 Progress Report
ERTS-1
a. Title: Evaluate ERTS imagery for mapping and detection
of changes of snowcover on land and on glaciers.
ERTS-A Proposal No.: 342-7
b. GSFC ID No. of P.I.: IN 045
c. Statement and explanation of any problems that are
impeding the progress of the investigation:
No official word has been received on the status of our
Data Analysis Plan dated 1 May 1973, which requested addi-
tional funds to study 1973 summer images; nor has any pre-
liminary information been forthcoming on the status of these
funds. Thus work has only proceeded at a low level of
effort, in order to save enough money to prepare the final
reports.
Although the spring and summer in the Pacific Northwest
have been abnormally clear and dry, cloudy periods coincided
with almost all of the ERTS passes over test sites 1 and 2
(Mt. Rainier and North Cascades). The single cloud-free
pass covered the west side of these areas only on 6 April.
Partly because of this problem, it has been difficult to
schedule U-2 overflights for use as "ground truth" for these
most important test sites.
d. Discussion of the accomplishments during the reporting
period and those planned for the next reporting period:
Incoming ERT images have been cataloged and given
cursory inspection. Certain images have been identified for
future study on the ESIAC at SRI or by optical techniques in
Tacoma. These include new tasks and extensions of work done
previously, as follows:
1. Differences in reflective signature between dry snow
and wet snow, especially in several major snowfields in the
Coast Mountains of southwest British Columbia.
2. Changes in snowcover in western Chugach Mountains
near Anchorage, Alaska, in same area as the thoroughly
analyzed 27 September 1972 image.
J3. Inventory and monitoring of glacier dammed lakes
(which can cause damage when they break out); lakes around
10 different glaciers in Alaska have been selected for this.
4. Measurement of change in termini in Hubbard and
Columbia tidal glaciers.
5. Continuation 6f work on measurement of snowcover in
specific drainage basins, equivalent snowline altitudes (ELA),
monitoring of surg ing glaciers, and image enhancement tech-
niques to better identify snow in shadow or in trees.
Several scene-corrected images have been received and
studied; because the radiemetric corrections have been applied
in blocks these images appear to be less useful for automatic
processing than the bulk system-corrected images.
Excellent U-2 imagery, flown for another investigator,
has been obtained of the Olympic Peninsula on 11 July. This
is being studied to see if another useful test can be made
of the automatic procedure (ESIAC) for measuring snow-covered
area from ERTS imagery. In this case, two ERTS passes on
consecutive days are required for analysis.
Dave Hirst, Photographic Technician, visited the ERTS
NDPF and EROS-Sioux Falls in order to better interface our
processing procedures with those of NASA and EROS.
e. Discussion of significant scientific results and their
relationship to practical applications or operational prob-
lems including estimates of the cost benefits of any signifi-
cant results.
NONE.
f. A listing of published articles, and/or papers, pre-
prints, in-house report, abstracts of talks, that were
released during the reporting period:
Research Symposium, "New Approaches to Snowpack Water
Resources Management through Electromagnetic Techniques,"
USGS, Menlo Park, California, 27 August 1973.
g. Recommendation concerning practical changes in operations,
additional investigative effort, correlation of effort and/or
results as related to a maximum utilization of the ERTS
Stystem:
NONE.
h. A listing by date of any changes in Standing Order Forms:
7 November 1972
1 May 1973
i. ERTS Image Descriptor forms:
In preparation.
j. Listing by data of any changed Data Request forms sub-
mitted to Goddard Space Flight Center/NDPF during the
reporting period:
NONE.
k. Status of Data Collection Platforms:
N/A


Evaluate ERTS imagery for mapping and detection of changes of snowcover on land and on glaciers

The author has identified the following significant results. Snowlines on a small (6 sq km) drainage basin were accurately measured without use of digital processing, and snow patches as small as 150 m (maximum dimension) were correctly identified, proving that the resolution of ERTS is ample for snow mapping needs. The area of snow cover on 10 individual drainage basins in the North Cascades, Washington, has been determined at 12 different times; these data can be used for more accurate forecasts of streamflow. Progress has been made in distinguishing snow in trees using multispectral analysis. Motion of the surging Tweedsmuir Glacier was measured. Velocities ranged from 2 to 88 m per day; a zone of intense crevassing also appeared to spread up and down the glacier (at about 200 m per day upglacier). This tentative result may be of great importance to an understanding of surging glacier dynamics. ERTS images also show that the most recent debris flow (20-21 August 1973) from Mount Baker can be clearly discerned and mapped, in order to monitor this potential hazard

"Made f'ailable under NASA sponsorship '
in the interest of early and wide dis- E 7. 4 - 7 1.S semination of Earth Resources Survey
Program information and without liability 
-~9-3
for any use made thereot."
EVALUATE ERTS IMAGERY FOR MAPPING AND DETECTION OF CHANGES OF
SNOWCOVER ON LAND AND ON GLACIERS
Mark F. Meier
U.S. Geological Survey
1305 Tacoma Avenue South
Tacoma, Washington 98402
'(E74-10710) EVALUATE ERTS IMAGERY FOR N74-31791
MAPPING AND DETECTION OF CHANGES OF
jSNOWCOVER CN LAND AND ON GLACIERS
'Semiannual Progress Report, 1 (Geological Unclas
Survey) 7 p_ HC $4.00 CSCL 08L G3/13 00710
1 July 1974
Type II Progress Report for Period 1 January 1974 - 30 June 1974
Prepared for:
Goddard Space Flight Center
Greenbelt, Maryland 20771
Publication authorized by the Director, U.S. Geological Survey
AUG 1 9 1974
Bgs902.6
https://ntrs.nasa.gov/search.jsp?R=19740023678 2020-03-23T03:47:37+00:00Z
TECHNICAL REPORT STANDARD TITLE PAGE
1. Report No. 2. Government Accession No. 3. Recipient's Cataloa No.
S itle and Subtitle 5. Report Date
EVALUATE ERTS IMAGERY FOR MAPPING AND 1 July 1974
DETECTION OF CHANGES OF SNOWCOVER ON LAND 6. Performing Organization Cod
AND ON GLACIERS (SR 342-7)
7. Author(s) 8. Performing Organization Report No.
Mark F. Meier (IN 045)
9. Performing Organization Name and Address 10. Work Unit No.
11. Contract or Grant No.
U. S. Geological Survey S-70243-AG
Tacoma, Washington 98402 13. Type of Report and Period Covered
12. Sponsoring Agency Name and Address Type II Progress Rpt
F. Gordon, Jr. 1 Jan 74 - 30 Jun 74
Goddard Space Flight Center 14. Sponsoring Agency Code
Greenbelt, Maryland 20771
15. Supplementary Notes
16. Abstract
Snowlines on a small (6 km2) drainage basin were accurately meas-
ured without use of digital processing, and snow patches as small.as
150 m (maximum dimension) were correctly identified, proving that the
resolution of ERTS is ample for snow mapping needs. The area of snow-
cover on 10 individual drainage basins in the North Cascades, Washing-
ton, has been determined at 12 different times; these data can be used
for more accurate forecasts of streamflow. Progress has been made in
distinguishing snow in trees using multispectral analysis. Motion of
the suraing Tweedsmuir Glacier wvas measured. Velocities ranged from
2 to 88-m per day; a zone of intense crevassing also appeared to spread
up and down the glacier (at about 200 m per .day upglacier). This ten-
tative result may be of great importance to an understanding of surging
glacier dynamics. ERTS images also show that the m6st recent debris
flow (20-21 August 1973) from Mount Baker can be clearly discerned.and
.mapped, in order to monitor this potential hazard.
17. Key Words (5. lected by Author(s)) 18. Distribution Statement
Snowlines
Snowcover
Glaciers
Glacier surges
Glaciolonv
j19. Security Clossif. (of this report) 20. Security Classif. (of this page) 21. No. of Pages 22. Price*
Unclassified Not Applicable 7
For 3ale by the Clearx house f~r FrecralScientifc and Tcchnical Info ation, 5oringfield. Virginia 22151.
Type II Progress Report
ERTS-1
a. Title: Evaluate ERTS imagery for mapping and detection of changes of
snowcover on land and on glaciers.
ERTS-A Proposal No.:' 342-7
b. GSFC ID No. of P.I.: IN 045
c. Statement and expalanation of any problems that are impeding the progress
of the investigation:
Missing data, because of cloud cover, non-acquisition, or non-transmittal,
is still a serious problem.
d. Discussion of the accomplishments during the reporting period and those
plahned for the next reporting period:
Snow-covered area (in kilometres and percent) has been measured for 10
individual drainage basins in the North Cascades, Washington, all or some
of which were measured with the Stanford ESIAC during 12 ERTS cycles. These
data are now being analyzed in terms of a hydrologic model, and 4 additional
basins and 1 additional cycle are being studied. Measurements have been
started of snow-covered area and snowline altitude on images of the Mount
Olympus region and an area in the southern Olympics to obtain a longer time-
series of data.
A scanning densitometer has been used at many different magnifications
and different resolution element sizes to study 70 mm ERTS transparencies
showing snowcover in small drainage basins, in order to evaluate resolution,
density contrasts at snow/no snow boundary, and accuracy of snow-covered
area measurements in presence of shadows on snow and other materials of
similar radiance (ice, firn, light-colored rock).
Experiments have been conducted on the ESIAC utilizing masks cut ac-
cording to topographic contours. By cycling through a registered set of
these masks on the display monitor, one can match the snowline to the best-
fitting contour. This "variable contour overlay" promises to be another
useful procedure for obtaining snow-covered area or snowline altitude.
High-altitude.(U-2) and low-altitude aircraft data on snowlines are
being analyzed as "ground truth" for the ERTS imagery. This is an ex-
tremely tedious process due to the complexity of the snowline, the prob-
lems with vegetation cover, and the relief distortion in photographs. Thus
attempts will be made to devise statistical sampling and other techniques
for streamlining the procedures.
Several other studies of snow-mapping accuracy are continuing, as are
evaluations of the several snow identification strategies which can be used
by eye or machine (i.e., simple density slicing, slicing on density gra-
dients, subjective or quantitative identification of snow in shadows, mul-
tispectral and cluster analysis, etc.). Preliminary work has been done on
all-digital processing. The problem of reading a combined signature of
snow and trees has been approached by using a 2-dimensional color-space
display (band 5 against band 6 or 7) in conjunction with the ESIAC. This
permits the rapid selection and comparison of training sets and study of
the fields they define on a color-space display.
Considerable additional work has been done on the measurement of ice
movement and the movement of kinematic waves of thickness or crevassing on
surging glaciers as seen on ERTS images, and on the monitoring of hazards
such as glacio-volcanic debris flows.
Seven articles or talks on ERTS results were prepared. Also, an
Operational Applications of Satellite Snowcover Observations program for
the Northwest has been discussed with officials of NASA, EROS, BPA, Corps
of Engineers, and NWS.
The next reporting period will be devoted to production of a final
report.
e. Discussion of significant scientific results and their relationship
to practical applications or operational problems including estimates of
the cost benefits of any significant results.
Snowlines on a small (6 km2) drainage basin were accurately identified
on bulk ERTS images without use of digital processing and results checked
with high-altitude and ground-based photography. The area and approximate
shape of snow patches as small as 20,000 m2 (maximum dimension: 150 m)
could be correctly identified with a magnifying scanning densitometer
using an 80 m circular resolution element. Thus the resolution of ERTS is
more than ample for most snow-mapping needs.
The area of snowcover on 10 individual drainage basins in the North
Cascades, Washington, has been determined for 29 July, 2 September, and
8 October 1972, and 30 May and 12 September 1973. In addition, snowcover
on many of these basins has been measured on 14 November 1972 and 6 January,
12 February, 7 April, 25 April, 12 May, and 11 August 1973. A semi-
automatic radiance threshold technique was employed. The result is a
unique record of the changing water storage as snow in these important
hydrologic units, the runoff of which is utilized for hydroelectric power,
dilution of wastes and heat, salmon migration, and irrigation. These data
will now allow a new type of hydrologic modelling to proceed which should
permit more accurate forecasts of streamflow.
A new technique has been developed for measuring snow-covered area or
snowline altitude semi-automatically. This variable contour overlay method
involves superimposing an ERTS image on a monitor (ESIAC) with a registered
series of contour masks which are rapidly cycled, thus permitting the snow-
cover to be matched efficiently to the best fit contour of altitude. Re-
peatability of 60 m in altitude is readily obtained.
Although it is not yet possible to measure snowcover on an ERTS image
by a fully automatic (digital processing) technique, progress has been made
in distinguishing snow from other terrain materials in the absence of
clouds. The band 7/band 5 radiance ratio is typically 0.5 for dry snow
and less than 0.48 for wet snow; other typical terrain radiances show appre-
ciably higher ratios. This technique may be of great value in identifying
snow in deep shadows, a severe problem with other techniques. Using a
color-space display connected to the ESIAC console, training sets could be
immediately identified with their position on 2-dimensional color-space
(usually band 5 against 6 or 7). As a result it was possible to define a
color-space area which was directly between the clusters attributed to
trees (evergreen) and snow. This presumably is a mixture of tree and snow
radiances, indicating that some radiance was derived from snow between the
nearly complete tree canopy. Using this technique, a mixed snow-tree area
was mapped around the pure snow area of Mount Olympus. Thus if the canopy
cover is not complete, it may be possible to map snow in forested terrains.
Motion of the Tweedsmuir Glacier was measured using ERTS images enlarged
1:50,000, using the facilities of the Geophysical Institute, University of
Alaska. Changes detected included a shock wave moving up and down the
glacier, the margin expanding, the moraine pattern deforming, and the mar-
ginal valley deepening. Velocities measured at 9 places in time and space
ranged from 2 to 88 m per day; these clearly show the increase and then
decrease in speed as the surge wave passed. These data have been confirmed
by independent measurements made at the site by a Canadian glaciologist. In
addition, these images suggest that a cone of intense crevassing (indicated
by a darkening of the snow radiance) spread up-glacier at a very high rate
of speed, about 200 m per day. This tentative result may be of great
importance to an understanding of surging glacier dynamics, as it apparently
shows the location where rapid movement began and how this rapid movement
spread along the length of the glacier.
Tweedsmuir Glacier is now damming the large Alsek River, and the future
release of this glacier dammed lake imperils settlements and a small indus-
try at Dry Bay, Alaska.
The motion of the Yentna Glacier during the concluding phase of its
surge was successfully measured by a "flicker" technique on the ESIAC
using images of two dates. It appears that displacements as small as 100
to 2,000 m can be measured, which is very close to the resolution limit
for a single ERTS image.
Mount Baker, Washington, has a large crater south of the summit and
an area north of the summit which emit considerable geothermal heat in the
form of fumaroles and hot ground. Temperatures here are being monitored
using an ERTS Data Collection Platform. Also, debris flows are occasion-
ally released from the crater due to water saturation at the base of a
heavy snowpack lying on hydrothermally altered hot ground. These debris
flows present a possible hazard to life and property, as they are dis-
charged down the Boulder Glacier toward Baker Lake, the upper of two major
hydroelectric power reservoirs which are situated above the populated
Skagit River valley. Study of ERTS images shows that the most recent
debris flow (20-21 August 1973) can be clearly discerned and mapped. Thus
ERTS images provide another important tool for monitoring this potential
hazard.
f. A listing of published articles, and/or papers, preprints, in-house
reports, abstracts of talks, that were released during the reporting
period:
Paper presented at Second Annual Symposium on Applications of Satellite
and Airplane Remote Sensing of Natural Resources in the Pacific Northwest:
Krimmel, R.M., Use of ERTS images in glacier studies.
Papers prepared for EROS book on use of ERTS images:
Post, Austin, Meier, M. F., and Mayo, L. R., Measuring the motion of
surging glaciers.
Krimmel, R. M., Post, Austin, and Meier, M. F., Monitoring surging
glaciers.
Frank, David, Debris avalanches at Mount Baker volcano.
Krimmel, R. M., and Meier, M. F., Measuring snow-covered area to
predict reservoir inflow.
Paper accepted for International Symposium on Remote Sensing in Glaciology,
Cambridge, England:
Krimmel, R. M., and Meier, M. F., Glacier applications of ERTS images.
Colloquium "Remote Sensing of Snow and Ice" given at the University of
Washington, 14 February, by M. F. Meier.
g. Recommendation concerning practical changes in operations, additional
investigative effort, correlation of effort and/or-results as related to
a maximumi utilization of the ERTS system.
None.
h. A listing by date of any changes in Standing Order Forms:
7 November 1972
1 May 1974
i. ERTS Image Descriptor forms:
In preparation.
j. Listing by date of any changed Data Request forms sibmitted to
Goddard Space Flight Center/NDPF during the reporting period:
3 May 1974
k. Status of Data Collection Platforms:
N/A


The author has identified the following significant results. The standard error of measurement of snow covered areas in major drainage basins in the Cascade Range, Washington, using single measurements of ERTS-1 images, was found to range from 11% to 7% during a typical melt season, but was as high as 32% in midwinter. Many dangerous glacier situations in Alaska, Yukon, and British Columbia were observed on ERTS-1 imagery. Glacier dammed lakes in Alaska are being monitored by ERTS-1. Embayments in tidal glaciers show changes detectable by ERTS-1. Surges of Russell and Tweedsmuir Glaciers, now in progress, are clearly visible. The Tweedsmuir surge is likely to dam the large Alsek River by mid-November, producing major floods down-river next summer. An ERTS-1 image of the Pamir Mountains, Tadjik S.S.R., shows the surging Medvezhii (Bear) Glacier just after its surge of early summer which dammed the Abdukagor Valley creating a huge lake and later a flood in the populous Vanch River Valley. A map was compiled from an ERTS-1 image of the Lowell Glacier after its recent surge, compared with an earlier map compiled from pain-stakingly compiled from a mosaic of many aerial photographs, in a total elapsed time of 1.5 hours. This demonstrates the value of ERTS-1 for rapid mapping of large features

"Made avallable unier NASAM sponsorsi p E10.
in the interest of early and wide dis- E7.4 10. o. 3
semination of Earth Resources Survey t Q - / 358 ~
Program information and without liability
for any use made thereof."
EVALUATE ERTS IMAGERY FOR MAPPING AND DETECTION OF CHANGES OF SNOWCOVER
ON LAND AND ON GLACIERS
Mark F. Meier
U.S. Geological Survey
Tacoma, Washington 98402
31 October 1973
Type I Progress Report for Period 1 September - 31 October 1973
E74-10037) EVALUATE ERTS IMAGERY FOR N74-1212
MAPPING AND DETECTION OF CHANGES OF
SNONCOVER ON LAND AND ON GLACIERS
Progress Report, 1 Sep._-; 31 (Geological Unclas
Survey) 4 p HC $3.00: CSCL 08L G3/13 00037
Prepared for:
Goddard Space Flight Center
Greenbelt, Maryland 20771
https://ntrs.nasa.gov/search.jsp?R=19740004012 2020-03-23T12:15:30+00:00Z
Type I Progress Report
ERTS-1
a. Title: Evaluate ERTS imagery for mapping and dection of changes of
snowcover on land and on glaciers.
ERTS-A Proposal No.: 342-7
b. GSFC ID No. of P.I.: IN 045
c. Statement and explanation of any problems that are impeding the
progress of the investigation:
No official word has been received on the status of our Data Analysis
Plan dated 1 May 1973, which requested additional funds to study 1973
summer images; nor has any preliminary information been forthcoming on
the status of these funds. Thus work has only proceeded at a low level
of effort, in order to save enough money to prepare the final reports.
Missing data continue to be a serious problem. For instance, in the
most intensively studied area (Test Site 1), data have been received from
only about 50% of the ERTS overpasses during the 1973 melt season. Some
of these missing data can be explained by cloud cover greater than stipu-
lated, but we are also missing crucial data at times of minimal clouds.
Thus the critical time-sequence analyses cannot be made. Difficulties
have also occurred in scheduling high-altitude aerial photography to
coincide with clear weather ERTS overpasses. This was not accomplished
until October 3, 1973, which was past the end of the melt season. Finally,
delay in transmission of data makes it impossible to produce timely releases
and reports (one may receive imagery one month after an ERTS pass, if not
one waits another month to make sure it is not coming routinely, then files
a Data Request and waits 1-3 months for it to come through, a total delay
of 3-5 months).
d. Discussion of the accomplishments during the reporting period and
those planned for the next reporting period:
Images sent for ESIAC analysis, mentioned in the last Type I report,
have not yet been processed at SRI.
ERTS imagery of the Olympic Peninsula, Washington, has been examined
as a substitute for the poor time series of North Cascades imagery. The
snowline altitude in the upper Hoh River basin has been determined using
topographic maps at 11 times from 30 July 1972 to 11 August 1973. These
results will be compared with equivalent snowline altitude (ESA) data
derived by the SRI ESIAC when it becomes available.
Operator variance measurements were made for a num-
ber of analysis techniques. High-altitude aircraft and ERTS imagery were
also used to estimate the uncertainty of detection of snowcover in forested
areas. These results were then compiled to yield estimates of standard
error of measurement of snowcovered area as a function of time of the
year for the North and Middle Cascades, Washington.
ERTS images were searched for evidences of dangerous glacier dammed
lakes, new surges, and major changes in tidal glacier termini. Unfortu-
nately, the two most important new surges in Western North America (Russell
and Tweedsmuir Glaciers) were detected by aerial photography before the
appropriate ERTS images were received fromn NASA. Excellent images have now
been received and will be compared with images from late summer 1972 to see
what changes could be detected. The surging Lowell Glacier was mapped,
and an ERTS image acquired over the Pamir Mountains was also studied. A
20 September 1973 image of Columbia Glacier, Alaska, received just before
this report was written, shows an almost catastrophic change in the calving
terminus and will be carefully compared with earlier images.
e. Discussion of significant scientific results and their relationship to
practical applications or operational problems including estimates of the
cost benefits of any significant results.
The standard error of measurement of snowcovered area in major drainage
basins in the Cascade Range, Washington, using single measurements of ERTSimages, was found to range from 11 percent (1 April) to 7 percent (30
September) during a typical melt season, but was as high as 32 percent in
midwinter. A typical basin snowcover diminishes at about 1.5 percent per
day during the melt 'season; thus these techniques cannot provide useful
data at time intervals less than 14-22 days. Although this is approximately
the return interval of ERTS, more frequent ERTS passes would be required
to take advantage of this powerful tool because of the cloud cover difficulty.
Many dangerous glacier situations in Alaska, Yukon, and British Columbia
were observed on ERTS imagery. Glacier dammed lakes in Alaska which arebeing monitored by ERTS include Skilak, Blockade, Strandline, George,
Tazlina-Nelchina Glacier lakes, Columbia Glacier Lake, Van Cleve, Berg, and
Canyon.
Embayments in tidal glaciers show changes detectable by ERTS. TheHubbard Glacier (previously discussed) shows continuing change. The Columbia
Glacier shows a huge embayment now forming which may presage a disasterous
retreat accompanied by a huge stream of icebergs into the navigable waters
of Prince William Sound.
Surges of Russell and Tweedsmuir Glaciers, now in progress, are clearly
visible in ERTS imagery. The Tweedsmuir surge is likely to dam the largeAlsek River by mid-November, producing major floods down-river next summer.
Russell Glacier is advancing into Upper Skolai Lake.
3
An ERTS image on 12 July 1973 of the Pamir Mountains, Tadjik S.S.R.,
has been obtained. It shows the surging Medvezhii (Bear) Glacier just
after its surge of early summer which dammed the Abdukagor Valley creating
a huge lake and later a flood in the populous Vanch River valley. Study
of this image shows six other undoubted surge-type glaciers (one of which
appears ready to surge) and at least 16 suspected surge-type glaciers.
Finally, a map was compiled from an ERTS image of the Lowell Glacier
after its recent surge, compared with an earlier map painstakingly com-
piled from a mosaic of many aerial photographs, both maps reduced to a
common map scale, and measurements made of the direction and amount of
surge displacements at three points along the lengthof the glacier--in
a total elapsed time of 1.5 hours. Thus is shown the value of ERTS for
rapid mapping of large features.
f. A listing of published articles, and/or papers, preprints, in-house
reports, abstracts of talks, that were released during the reporting period:
Presentation "ERTS applications to snow and ice" at meeting of Committee
on Polar Research, National Academy of Sciences, Boulder, Colorado, 26 October
1973.
g. Recommendation concerning practical changes in operations, additional
investigative effort, correlation of effort and/or results as related to
a maximum utilization of the ERTS system:
None.
h. A listing by date of any changes in Standing Order Forms:
7 November 1972
1 May 1973
i. ERTS Image Descriptor forms:
In preparation.
j. Listing by date of any changed Data Request forms submitted to Goddard
Space Flight Center/NDPF during the reporting period:
29 October 1973.
k. Status of Data Collection Platforms:
N/A


The author has identified the following significant results. A possibly more accurate method to determine snowcover area change has been tried; snowcover area change over periods of an ERTS-1 cycle are very useful in determining energy balances over regional areas and to determine snow depth as a function of altitude. Also since shadow and cloud cover areas are highlighted this method may be a step toward more complete machine processing

fMado available under NASA sponsorsh'l
In the interest of early and wide dis-
semination of Earth Resources Survey
Program information and without liability
ior any use made thereof."
E7.3 1 0 5.5 9
CR ) /5/68 
EVALUATE ERTS IMAGERY FOR MAPPING AND DETECTION OF CHANGES OF SNOWCOVER
ON LAND AND ON GLACIERS
Mark F. Meier
U.S. Geological Survey
Tacoma, Washington 98402
30 April 1973
Type I Progress Report for Period 1 March 1973 - 30 April 1973
E73-10559) : EVALUATE ERTS IMAGERY FOR
MAPPING AND DETECTION OF CHANGES OF
SNOWCOVER ON LAND AND ON GLACIERS
Proqress Report, 1 Mar. - 30 (Geological
Survey) 4 p HC $3.00 CSCL 08B
Prepared for:
Goddard Space Flight Center
Greenbelt, Maryland 20771
Publication authorized by the Director, U.S. Geological Survey
N73-23431
Unclas
G3/13 00559
https://ntrs.nasa.gov/search.jsp?R=19730014704 2020-03-23T05:08:50+00:00Z
Type I Progress Report
ERTS-1
a. Title: Evaluate ERTS imagery for mapping and detection of changes
of snowcover on land and on glaciers.
ERTS-A Proposal No.: 342-7
b. GSFC ID No. of P.I.: IN 045
c. Statement and explanation of any problems that are impeding the
progress of the investigation:
Data delivery is now excellent, although the wintertime images are
not as important as spring or summer data. Long delays in data requests
inhibit progress.
d. Discussion of the accomplishments during the reporting period and
those planned for the next reporting period:
Snowlines were drawn for South Cascade Glacier basin J(3x5 km) for
three cycles using greatly enlarged ERTS images. This basin was chosen
because a large amount of ground truth and aircraft data exist. It was
shown that useful snowlines can be derived from ERTS data even in a basin
as small as this. It was also a helpful exercise to relate ERTS resolu-
tion to ground truth, especially in areas of partial snowcover with
patches smaller than those resolvable from ERTS imagery.
Robert M. Krimmel spent three days at Stanford Research Institute
working with William Evans on ESIAC. The purpose of this visit was to
give another member of our staff direct expe'ience with the ESIAC, to
attempt several new experiments, and to clear up some questions between
the investigators of Project 342-7 and Project 342-B.
The most promising experiment was to directly compare sequential
frames of snowline data. This was tried using color transparencies of
an oblique, ground-based time-lapse sequence. By playing a positive of
one date against a negative of another date, areas that were first snow-
covered and later free of snow are highlighted. The highlighted areas
are easily masked, and the area measured. Since using the ground views,
SRI personnel have also tried using ERTS images with some success.
The ESIAC was used to form a binary mask of the snowlines in the
South Cascade Glacier basin as a direct bmparison of results using
optical methods versus electronic methods.
/
Frames of Mt. Rainier and Thunder Creek areas, previsouly analyzed
by SRI, were recalled and Krimmel (an experienced glaciologist) formed
video masks independently of SRI influence, confirming the techniques
evolved by SRI.
Attention next period will be working with SRI toward refining the
method of direct comparison of sequential images to derive snowcover
area change data. We also expect to begin planning and coordination
of anticipated U-2 overflights and associated ground truth.
e. Discussion of significant scientific results and their relationship
to practical applications or operational problems including estimates
of the cost benefits of any significant results.
A possibly more accurate method to determine snowcover area change
has been tried; snowcover area change over periods of an ERTS cycle are
very useful in determining energy balances over regional areas and to
determine snow depth as a function of altitude. Also, since shadow and
cloud cover areas are highlighted this method may be a step toward more
complete machine processing.
f. A listing of published articles, and/or papers, pre-prints, in-house
reports, abstracts of talks, that were released during the reporting
period:
Paper "Evaluation of ERTS imagery for mapping and detection of
changes of snowcover on land and on glaciers," was read at ERTS-1
Symposium, Greenbelt, Maryland, March 5-8.
Papers "New ways to monitor the'mass and areal extent of snowcover"
and "Applications of ERTS imagery to snow and glacier hydrology" were
invited for Symposium on Approaches to Earth Survey Problems through
the Use of Space Techniques, COSPAR, Konstanz, Germany; abstracts have
been submitted.
g. Recommendation concerning practical changes in operations, additional
investigative effort, correlation of effort and/or results as related to
a maximum utilization of the ERTS system:
Urgently need additional U-2 overflighits and ERTS imagery during
summer of 1973 in order to have useful time sequence through a complete
melt season.
h. A listing by date of any changes in Standing Order Forms:
7 November 1972.
i.. ERTS Image Descriptor forms:
In preparation.
j. Listing by date of any changed Data Request forms submitted to
Goddard Space Flight Center/NDPF during the reporting period:
All requests originated by User Services, GSFC.
k. Status of Data Collection Platforms:
N/A


The author has identified the following significant results. The area of snow cover on land was determined from ERTS-1 imagery. Snow cover in specific drainage basins was measured with the Stanford Research Institute console by electronically superimposing basin outlines on imagery, with video density slicing to measure areas. Snow covered area and snowline altitudes were also determined by enlarging ERTS-1 imagery 1:250,000 and using a transparent map overlay. Under very favorable conditions, snowline altitude was determined to an accuracy of about 60 m. Ability to map snow cover or to determine snowline altitude depends primarily on cloud cover and vegetation and secondarily on slope, terrain roughness, sun angle, radiometric fidelity, and amount of spectral information available. Glacier accumulation area ratios were determined from ERTS-1 imagery. Also, subtle flow structures, undetected on aerial photographs, were visible. Surging glaciers were identified, and the changes resulting from the surge of a large glacier were measured as were changes in tidal glacier termini

The author has identified the following significant results. A new procedure to determine snowcovered areas has been devised. Aside from problems in heavily forested areas this method shows promise in predicting snowmelt runoff from mountain areas and will also assist in energy balance modeling of large snowfields. Snowcover results compare favorably with measurements made by high altitude aircraft photography. Changes in snowcover in areas as small as 3 x 5 km can be determined from ERTS-1 images by both optical and electronic methods. Snowcover changes determined by these two methods in the experimental South Cascade Glacier Basin were verified by field mapping. Image enahancement techniques on ERTS-1 images of large Alaskan glaciers (the Hubbard, Yentna, and Kahiltna) have given new insights into the large-scale structures and flow dynamics of these potentially hazardous glaciers. The Hubbard Glacier, in particular, is one which poses a threat to man and should be monitored for future changes

E7.4- 1 0.8 j
EVALUATE ERTS IMAGERY FOR MAPPING AND DETECTION OF CHANGES OF
SNOWCOVER ON LAND AND ON GLACIERS
Mark F. Meier "Made available under NASA sponsorship
U.S. Geological Survey in the irterest of early and wide dis-
1305 Tacoma Avenue Southinti of arl a we
Tacoma, Washington 98402 semination of Earth Resources Survey
Program information and without liability
for any use made thereotf,"
1 July 1973
Type II Progress Report for Period 1 January 1973 - 3DJune 1973
(E74-10812) EVALUATE ERTS IAGERY FOR N75-0539
MLAPPING AND DETECTION OF CHANGES OF
SNOWCOVER ON LAND AND ON GLACIERS
Semiannual Progress Report, 1 (Geological Unclas
\Survey) 7 p HC $3.25 CSCL 08L G3/43 00812
Prepared for:
Goddard Space Flight Center
Greenbelt, Maryland 20771
Publication authorized by the Director, U.S. Geological Survey
https://ntrs.nasa.gov/search.jsp?R=19750002467 2020-03-23T03:23:09+00:00Z
1. Report No. 2 . Government Accession No. 3. Recipients Cartola No.
Slsitle and Subtitle 5. Report rote
EVALUATE ERTS IMAGERY FOR MAPPING AND 1 July 1973
DETECTION OF CHANGES OF SNOWCOVER ON LAND 6. Performing Orgoanization Cod-
AND ON GLACIERS (SR 342-7)
7. Author(s) 8. Performing Organization Report No.
Mark F. Meier (IN 045)
9. Performing Organization Name and Address 10. Work Unit No.
U. S. Geological Survey 11. Contract or Grant No.U. S GelogcalSurvey
Tacoma, Washington 98402 S-70243-AG
13. Type of Report and Period Covered
12. Sponsoring Agency Name and Address Type II Progress Rpt
1. Gordon, Jr. Jan 73 - 30 Jun 73
F. Gordon, Jr.
Goddard Space Flight Center 14. ponsoring Agency Code
Greenbelt, Maryland 20771
15. Supplementary Notes
16. Abstract
A new procedure to determine snowcovered areas has been devisedc,
" 'isl.ng-e-SR$ . Aside from problems in heavily forested areas
this method shows promise in predicting snowmelt runoff from mountain
areas and will also assist in energy balance modeling of large snow-
fields. Snowcover results in this study compare favorably with meas-
urements made by high-altitude aircraft photography.
Changesl in snowcover in areas as small as 3 x 5 km can be determinec
from ERTS images by both optical and electronic methods. Snowcover
changes determined by these two methods in the experimental South Cas-
cade Glacier Basin were verified by field mapping.
Image enhancement techniques on ERTS images of large Alaskan gla-
ciers (i.e., the Hubbard, Yentna, and Kahiltna) have given new ins.ights
-into the large-scale structures and flow dynamics of these potentially
hazardous glaciers. The Hubbard Glacier, in particular, is one which
poses a threat to man and should be monitored for future changes.
17. Key Words (S. facted by Author(s)) 18. Distribution Statement
Snowlines
Snowcover
Glaciers
Glacier surges
Glaciolov _ __
19. Security Clossif. (of this report) 0. Security Classif. (of this page) 21. No. of Pages 22. Price*
Unclassified Not Applicable 7
*For sale by the Clearinihouse for Federal Scientific and Technical Information. Springfield, Virginia 221!1.
REPRODUCIBILITY OF THE
2 ORIGINAL PAGE IS POOR
Type II Progress Report
ERTS-1
a. Title: Evaluate ERTS Imagery for Mapping and Detection of Changes
of Snowcover on Land and on Glaciers.
ERTS-A Proposal No.: SR 342-7
b. GSFC ID No. of P.I.: IN 045
c. Statement and explanation of any problems that are impeding the
progress of the investigation:
No major problems. Minor problems include long delays in receiving
data following Data Requests, some imagery too dark for analysis, diffi-
culty with radiometric calibration of images, and no word yet received
on status of Data Analysis Plan.
Snowlines were drawn for South Cascade Glacier Basin (3 x 5 km) for
three cycles using greatly enlarged ERTS images. This basin was chosen
because a large amount of ground truth and aircraft data exist. This
was a productive study of the relation of ERTS imagery to ground truth,
especially in areas of partial snowcover with patches smaller than those
resolvable from ERTS imagery.
Robert M. Krimmel spent three days at Stanford Research Institute
working with William E. Evans and others on the Electronic Image Analysis
Console (ESIAC). The purpose of this visit was to give another member
of our group direct experience with the ESIAC, to attempt several new
experiments, and to clear up some questions between the investigators
of Project 342-7 and Project 342-B.
The most promising experiment was to directly compare sequential
frames of snowline data. This was tried using color transparencies of
an oblique, ground-based time-lapse sequence. By playing a positive of
one date against a negative of another date, areas that were first snow-
covered and later free of snow are highlighted. The highlighted areas
are easily masked, and the area measured. Since using the ground views
SRI personnel were asked to use ERTS images of Mount Rainier in this
way to measure changes in snowcovered (and shadowed) area which could
then be compared with differences between direct measurements of snow-
covered area on different dates.
The ESIAC was also used to form a binary mask of the snowlines in
the South Cascade Glacier Basin as a direct comparison of results using
optical methods versus electronic methods.
3
Frames of Mount Rainier and Thunder Creek areas, previously analyzed
by SRI, were recalled and Krimmel (an experienced glaciologist) formed
video masks independently of SRI influence confirming the negligible
operator-bias in the techniques evolved by SRI.
Electronic image enhancement techniques were tried by Krimmel on
several glacier images to investigate certain problems in our current
understanding of glacier flow, glacier surges, and the potentially
hazardous advance of Hubbard Glacier.
Considerable effort was devoted by SRI personnel to generating curves
of apparent snowcovered area versus gray scale value for specific drain-
age basins. These curves were then studied by comparison with results
from planimetering snowlines on high-altitude aircraft images. Aircraft
snowline data were also transferred to enlarged ERTS images for study.
As a result the discrepancies between aircraft and ERTS data have been
largely resolved and standardized analysis techniques have been evolved.
Average snowline altitudes were measured over about 800 5-km squares
of 27 September images in the Anchorage area and the results contoured.
The concept of an equivalent snowline altitude (ESA) was developed and
many examples calculated. A hydrologic analysis was made of the changing
snowcover of the Thunder Creek drainage basin. Papers were prepared for
the 5-9 March ERTS-1 Symposium and for the 23-25 May Symposium on
Approaches to Earth Survey Problems Through the Use of Space Techniques,
COSPAR, Konstanz, Germany.
.Attention next period will be concentrated on analysis of the 1973
melt season data, utilizing high-altitude aircraft flights shceduled to
coincide with clear weather ERTS passes, and comparison of results from
this abnormally low snow year with results from the 1972 abnormally high
snow year. Special attention will be given to the problem of locating
the snowline in forested terrain. Quantitative results will be produced
more rapidly now that analysis procedures have been developed. The date-
to-date differencing technique will be further studied and the accuracy
of this method evaluated. Also, glacier surges and other features of
interest will be monitored and studied.
e. Discussion of significant scientific results and their relationship
to practical applications or operational problems including estimates
of the cost benefits of any significant results:
A procedure to derive snowcovered area values for specific drainage
basins has been devised using the SRI ESIAC. This technique has been
repeatedly checked and calibrated with independent data; however, prob-
lems still exist when snowcover exists in forested terrain. Sample
results for basins in the North Cascades, Washington, are given in
Table 1.
4
Table l.--Area of snow in specific drainage basins, North Cascades,
Washington, 1972
Drainage basin Snowcovered area, in km2 , on given date
No. Name 29 July 2 Sept. 8 Oct. 14 Nov.
1755 Thunder Cr. 105 59 40 --
1825 Cascade R. 139 66 42 --
1434 South Fork Snoqualmie R. -- .7 .4 12*
1413+ North plus Middle Fork
-- '27 14 29
1420 Snoqualmie R.
1330 South Fork Skykomish R. -- 27 18 52
*Value slightly uncertain because of partial cloud cover.
These results supersede some preliminary uncalibrated values reported
previously. In addition, the snowcover of the Mount Rainier areas has
been measured over a longer sequence, using several different techniques,
as given in Table 2.
Table 2.--Area of snowcover, Mount Rainier, Washington, 2 June 1972 to
11 February 1973.
Snowcovered area, in km2 , on given date
From From ERTS
Date aircraft By direct measurement By date-to-date subtraction*
2 June 760
29 July 339+ ** 293
10 August 147
2 September 120 119+ ** 168
8 October 108 96
14 November 184 182
2 December 206 232
6 January 305
21 January 302
11 February 431
* Date-to-date differences added to 29 July and 2 September direct meas-
urement values and then averaged to obtain a total area value.
** Shadowed areas, believed to be mostly snowcovered, not evaluated.
Results such as these should prove to be very useful in predicting
inflow to reservoirs (using the snow depletion curve method) and to
determine energy balance and snowmelt over regional areas for both water
management and scientific purposes.
5
A new concept was developed which has proven to be useful in inter-
polating, extrapolating, or generalizing mountain snowcover data: the
equivalent snowline altitude (ESA). The area/altitude function of most
drainage basins or mountain massifs is known or can be easily measured.
The ESA is then defined as that altitude above which the area of a basin
or mountain is equal to the area of snowcover. Snowcovered area can be
measured quickly and easily, and from this the ESA is determined. The
ESA can be used directly in numerical modelling of regional heat balances,
or it can be used to derive snowcovered area data from nearby basins
which are cloud covered or not imaged. First introduced at the ERTS-1
Symposium in March 1973, it is already in use by several other ERTS
investigators.
In spite of the rather crude resolution of ERTS imagery, it was found
that snowcovered area could be measured in very small, experimental
drainage basins. For instance, snowcover data have been obtained for
several dates both optically (zoom-transfer scope) and electronically
(ESIAC) for the South Cascade Glacier Basin, 3 km wide by 5 km long.
These results were verified by field mapping.
Study of time-sequence and individual ERTS images of nine glaciers
using image enhancement techniques has revealed much new information.
A large medial "structure" in the accumulation area of Hubbard Glacier
was discovered for the first time in spite of detailed maps and abundant
aerial photography. Knowledge of this structure adds to our understanding
of the drainage basin and dynamics of this huge glacier which threatens
to close off Russell Fiord and endanger the salmon canning industry near
Yakutat, Alaska.
Documentation of the motion of the surging Yentna Glacier was continued
during the 1972-73 winter using ERTS imagery. Perhaps the most interesting
discovery of this project is that of a periodically repeating series of
steps or waves on the nearby Kahiltna Glacier, which had been thought to
be a nonsurging glacier. These enigmatic features were first discovered
by image enhancement procedures using the ESIAC.
f. A listing of published articles and/or papers, pre-prints, in-house
reports, abstracts of talks, that were released during the reporting
period:
Paper "Evaluation of ERTS imagery for mapping and detection of changes
of snowcover on land and on glaciers," was read at ERTS-1 Symposium,
Greenbelt, Maryland, 5-8 March.
Papers "New ways to monitor the mass and areal extent of snowcover"
and "Applications of ERTS imagery to snow and glacier hydrology" were
invited for Symposium on Approaches to Earth Survey Problems Through the
Use of Space Techniques, COSPAR, Konstanz, Germany, 23-25 May; papers
have been submitted for publication in the proceedings.
6
g. Recommendation concerning practical changes in operations, additional
investigative effort, correlation of effort and/or results as related to
a maximum utilization of the ERTS system:
Urgently need additional U-2 overflights and ERTS imagery during
summer of 1973 in order to have useful time sequence through a complete
melt season.
h. A listing by date of any changes in Standing Order Forms:
7 November 1972.
i. ERTS Image Description forms:
In preparation.
j. Listing by date of any changed Data Request forms submitted to
Goddard Space Flight Center/NDPF during the reporting period:
16 January 1973
23 February 1973
18 April 1973
k. Status of Data Collection Platforms:
N/A
7


The author has identified the following significant results. The percentage of snow cover area on specific drainage basins was measured from ERTS-1 imagery by video density slicing with a repeatability of 4 percent of the snow covered area. Data from ERTS-1 images of the melt season snow cover in the Thunder Creek drainage basin in the North Cascades were combined with existing hydrologic and meteorologic observations to enable calculations of the time distribution of the water stored in this mountain snowpack. Similar data could be used for frequent updating of expected inflow to reservoirs. Equivalent snowline altitudes were determined from area measurements. Snowline altitudes were also determined by combining enlarged ERTS-1 images with maps. ERTS-1 imagery was also successfully used to measure glacier accumulation area ratios for a small test basin

"Made available under Pi~SA sptntstti
in the interest ofaar e ar,;c we dis
semination of Earth Resources Survey
Program information and without liability
for any use made thereof."
1 0.2 7? 9
/3 /106
EVALUATE ERTS IMAGERY FOR MAPPING AND DETECTION OF CHANGES OF SNOWCOVER
ON LAND AND ON GLACIERS
Mark F. Meier
U.S. Geological Survey
Tacoma, Washington 98402
'
27 February 1973
Type I Progress Report for Period 1 January 1973 
- 28 February 1973
E73- 9 ) EVALUATE ERTS IMAGERY FORN73193 MAPPING AND DETECTION OF CHfANGES OF N73-19
3 7 4SNOWCOVER ON LAND AND ON GLACIERS s
Proqress Report, 1 Jan. 
- 28 (Geological
Survey) 3 p HC $3.00 CSCL Unclas00379CSCL 08L G3/13 00379
Prepared for:
Goddard Space Flight Center
Greenbelt, Maryland 20771
Publication authorized by the Director, U.S. Geological Survey
Er. 3
Fz .3
https://ntrs.nasa.gov/search.jsp?R=19730010647 2020-03-23T03:33:53+00:00Z
Type I Progress Report
ERTS-1
a. Title: Evaluate ERTS imagery for mapping and detection of changes
of snowcover on land and on glaciers.
ERTS-A Proposal No.: 342-7
b. GSFC ID No. of P.I.: IN 045
c. Statement and explanation of any problems that are impeding the
progress of the investigation:
1. A standing order change request was submitted 7 November 1972
and resubmitted in mid-January. As of this date we have had no infor-
mation about this important action.
2. A data request was submitted 16 January for essential data not
supplied under our existing standing order. Nothing has been received
as of this date. Attempts to obtain essential data from EROS, Sioux
Falls, have also resulted in long delays.
3. Many images taken in October and November are too dark for
analysis.
4. As described in my letters to NASA-GSFC on 1 November, 13 December,
and 14 December, distribution of data to me has been spotty and incomplete,
especially for cycle I. The problem persists with little change.
d. Discussion of the accomplishments during the reporting period and
those planned for the next reporting period:
Additional data on area of snowcover were obtained from ERTS images
using the SRI ESIAC and by planimetering photographic enlargements.
Enlargements of U-2 images were also measured, and U-2 data were trans-
ferred to enlarged ERTS images for comparison. Average snowline altitudes
were measured over about 800 5-km squares of 27 September images in the
Anchorage area and the results contoured. The concept of an equivalent
snowline altitude (ESA) was developed and many examples calculated. A
hydrologic analysis was made of the changing snowcover of the Thunder
Creek drainage basin. A paper was prepared for the March 5-9 ERTS-1
Symposium.
Attention next period will be directed to calibration of ESIAC pro-
cedures for locating the snow/no-snow boundary, additional area measure-
ments, and further study of the 27 September snowlines in Alaska.
I
e. Discussion of significant scientific results and their relationship
to practical applications or operational problems including estimates
of the cost benefits of any significant results.
The percentage of snowcover area on specific drainage basins was
measured from ERTS imagery by video density slicing with a repeatability
of 4 percent of the snowcovered area. Data from ERTS images of the melt
season snowcover in the Thunder Creek drainage basin in the North Cascades
were combined with existing hydrologic and meteorologic observations to
enable calculations of the time distribution of the water stored in this
mountain snowpack. Similar data could be used for frequent updating of
expected inflow to reservoirs. Equivalent snowline altitudes were deter-
mined from area measurements. Snowline altitudes were also determined
by combining enlarged ERTS images with maps. ERTS imagery was also suc-
cessfully used to measure glacier accumulation area ratios for a small
test basin.
f. A listing of published articles, and/or papers, pre-prints, in-house
reports, abstracts of talks, that were released during the reporting
period:
Abstract for ERTS-1 Symposium, "Evaluation of ERTS imagery for mapping
and detection of changes of snowcover on land and on glaciers."
g. Recommendation concerning practical changes in operations, additional
investigative effort, correlation of effort and/or results as related to
a maximum utilization of the ERTS system:
Need additional U-2 overflights and ERTS imagery during summer of
1973 in order to have a useful time sequence.
h. A listing by date of any changes in Standing Order Forms:
7 November 1972, but no notice of action yet received.
i. ERTS Image Descriptor forms:
In preparation.
j. Listing by date of any changed Data Request forms submitted to
Goddard Space Flight Center/NDPF during the reporting period:
16 January 1973
23 February 1973
k. Status of Data Collection Platforms:
N/A


The author has identified the following significant results. Preliminary results on the feasibility of mapping snow cover extent have been obtained from a limited number of ERTS-1 images of mountains in Alaska, British Columbia, and Washington. The snowline on land can be readily distinguished, except in heavy forest where such distinction appears to be virtually impossible. The snowline on very large glaciers can also be distinguished remarkably easily, leading to a convenient way to measure glacier accumulation area ratios or equilibrium line altitude. Monitoring of large surging glaciers appears to be possible, but only through observation of a change in area and/or medial moraine extent. Under certain conditions, ERTS-1 imagery appears to have high potential for mapping snow cover in mountainous areas. Distinction between snow and clouds appears to require use of the human eye, but in a cloud-free scene the snow cover is sufficiently distinct to allow use of automated techniques. This technique may prove very useful as an aid in the monitoring of the snowpack water resource and the prediction of summer snowmelt runoff volume

.t/I ~ - I. . '. • -
, hltJ{Ji). 8ViWaIJle UI;dcr tii\S.4 SP(ji;~'O~;'-;iiP"
il1 tl"" 'nLo -",.! {)I II, • Il,; 'Illtlv~'" I (.':,'. ',' ,1"lj I' I'lfl (--t ....~ .. \, • \;. J I':"
semination of E~ltf; }(C~;ouicr;s Survey
Program iOformJtiollilnd wilhout liabiiitv
. for any lise made l/iercof." .
EVALUATE ERTS HIAGERY FOR jlIAPPI\G i\,\;D DETECTIm·l OF CHANCES OF SNm;COVER
0>: LXW .'\:\D 0:; GL:\C lERS
~.Iark f'. ~Ieier
U.S. Geological Survey
1305 T;leoma Avenue South
Tacoma, Washington 98402
24 October 1972
Ty~e I Progress Report for Period 1 September 1972 - 31 October 1972
Prepared for:
Goddard Spac~ Flight Center
Greenbelt, Maryland 20771
-. R~produce-d by- -
NATIONAL TECHNICAL
.. INFORMATION SERVICE
U 5 Department of Commerce
Spring!ield VA 22151
Publication authorized by the Director, U.S. Geological Survey
https://ntrs.nasa.gov/search.jsp?R=19730003610 2020-03-23T06:17:21+00:00Z
Type I Progress Report
ERTS-A
a. Title: Evaluate ERTS Imagery for Mapping and Detection of Changes
of Snowcover on Land and on Glaciers.
ERTS-A Proposal No.: SR 342-7
b. GSFC ID No. of P.I.: IN 045
c. StatelJ)ent and explanation of any'problems that are impeding the
progress of the investigation:
Our Standing Order Form request~ data irrespective of cloud cover
from a large area plus six small test sites. As of 24 October, ERTS-I
should have produced more than 853 frames (for each band) over our
large area alone. We have, however, received a total of only 53 dis-
crete frames, about half of which have useful data. 'These have been
so widely and randomly distributed in time and space that we still
have no data which can be used for regional snowline mapping, and we
have no data (except for one small area away from our main test sites
\"heretwo orbits overlap) which can be used for time-sequence analysis.
As these are the main thrusts of the proposal, little has been accom-
plished.
In particular, we still lack the most important midsummer imagery
(28 July and 15 August) of our highest priority test sites #1 and 2
(\\'ashington State) to relate to each other and to the 10 August U-2
flight (from which we have not yet received metric camera data either).
We have ilO more than one image from our other high-priority, small-area
test sites #3, 4, 5, and 6 (Alaska) and each of these shows complete
cloud cover.
d. Discussion of the accomplishments during the reporting period and
those planned for the next reporting period:
Images from 2 June U-2 mission over test sites 1 and 2 have been
studied with varying amounts of resolution and in comparison with low-
altitude or ground-level data in an attempt to devise a system for
identifying the snowline in heavy timber. The problem is receiving
further study.
ERTS images began to arrive on 19 September. A system to catalog,
identify, and retrieve data from a large collection of material was
devised and implemented, but the expected large amount of material has
not yet appeared.
Preliminary studies have been made of ERTS images from test sites
I and 2 (2 September) and excellent quality images from the Western
St. Elias-h'rangell ~Iountains. These studies have been directed to the
accuracv of snowline definition at the end of swnmer (no snow in forest),
:md SOl:l~ hand planiraetry of snow-covered area has been clone. Selected
images have been set up on tlle Stanford Research Institute Cloud Console
for automatic processing during the week of 24-27 October. Images of
Alaskan glaciers have been studied to observe firn lines and the charac-
teristic patterns of glacier surges.
e. Discussion of significant scientific results and their relationship
to practical applications or operational problems including estimates
of the cost benefits of any significant results:
Preliminary results on the'feasibility of mapping snowcover extent
have been obtained from a limited number of ERTS~1 imaies of mountains
in Alaska, British COlumbia, and Washington. l~e snowline on land can
be readily distinguished, except in heavy forest where such distinction
appears to be virtually impossible. The snowline on very large gtaciers
can also be distinguished remarkably easily, leading to a convenient way
to measure glacier accumulation area ratios (AAR) or equilibrium line
altitude (ELA). Monitoring of large surging glaciers appears to be
possible, but only through observation of a change in area and/or medial
moraine extent. Imagery in green or red light (MSS bands 4, 5) shows
the snowline more clearly in most areas than imagery in infrared light
(0155 band 6). The distinction between snow on large snoldields and
stratus-type clouds is very difficult, but the distinction can be made
fairly easily where either the snow pattern or the clouds show definite
structure. Infrared light (~1SS band 6) appears to be advantageous for
distinguishing snow from clouds.
Under certain conditions, ERTS imagery appears to have high potential
for mapping snowcover in mountainous area. Distinction between snow.and
clouds appears to require use of the human eye, but in a cloud-free s,cene
the snowcover is sufficiently distinct to allow use of'automated tech-
niques. This technique may prove very useful as an aid in the monitoring
of the snowpack water resource and the prediction of summer snowmelt run-
off volume.
Category designation: 4G, 4H, 2C, 20
f. A listing of published articles, and/or papers, pre-prints, in-house
reports, abstracts of talks, that were released during the reporting
period:
N.A.
g. Recommendation concerning practical changes in operations, additional
investigative effort, correlation of effort and/or results as related to
a maximum utilization of the ERTS system:
N.A.
/'j.
11. A listing by date of any changes in Standing Order Forms:
N.A.
i .' ERTS Image Descriptor forms:
Under preparation.
j. Listing by date of any changed Data Request forms submitted to
Goddard Space Flight Center/NDPF during the reporting period:
N.A.


The author has identified the following significant results. Snowlines on a small drainage basin were accurately identified on bulk ERTS-1 images without use of digital processing, and results checked with high altitude and ground-based photography. The area and approximate shape of snow patches as small as 20,000 sq m could be correctly identified with a magnifying scanning densitometer. The resolution of ERTS is more than ample for most snow mapping needs. Mount Baker, Washington, has a large crater south of the summit and an area north of the summit which emit considerable geothermal heat in the form of fumaroles and hot ground. Temperatures are being monitored using an ERTS DCS. Debris flows are occassionally released from the crater due to water saturation at the base of a heavy snowpack lying on hydrothermally altered hot ground. These debris flows present a possible hazard to life and property, as they are discharged down the Boulder Glacier toward Baker Lake, the upper of two major hydroelectric power reservoirs which are situated above the populated Skagit River Valley. ERTS-1 images show that the most recent debris flow (20-21 August 1973) can be clearly discerned and mapped. ERTS images provide another important tool for monitoring this potential hazard

" nMae valable under I~ASA si ft To
In the interest of eadry and wide, dis-
semination of Earth Resources Survey E7.- 1Program information and without liability
nr .ay st made thereot," N- / 7/
EVALUATE ERTS IMAGERY FOR MAPPING AND DETECTION OF CHANGES OF SNOWCOVER
ON LAND AND ON GLACIERS
Mark F. Meier
U.S. Geological Survey
Tacoma, Washington 98402
30 April 1974
Type I Progress Report for Period 1 March - 30 April 1974
(E74-10606) EVALUATE ERTS INAGERY FOR N74-28839
WAPPIVG AND DETECTION OF CHANGES OF
SNOWCOVER ON LAND AND ON GLACIERS
Progress Report, 1 Mar. - 30 (Geological Unclas
Survey) 4 p HC $4.00 CSCL 08L G3/13 00606
Prepared for:
Goddard Space Flight Center
Greenbelt, Maryland 20771 [
JUN 0 94
88 902.6
https://ntrs.nasa.gov/search.jsp?R=19740020726 2020-03-23T05:32:54+00:00Z
Type I Progress Report
ERTS-1
a. Title: Evaluate ERTS imagery for mapping and detection of changes
of snowcover on land and on glaciers.
ERTS-A Proposal No.: 342-7
b. GSFC ID No. of P.I.: IN 045
c. Statement and explanation of any problems that are impeding the
progress of the investigation:
Acquisition of images taken prior to the 30 November cutoff date is
still not complete. For some passes with acceptable cloud cover no data
have been received; for some other passes the full set of frames or the
full set of spectral bands has not been received. Data analysis has been
hampered by this spotty receipt of primary information. Some cloud-free
images of our critical test areas have been obtained from the University
of Alaska in order to permit work to proceed on a timely basis.
d. Discussion of the accomplishments during the reporting period and
those planned for the next reporting period:
Additional North Cascades drainage basins or subbasins have been
measured on the Stanford ESIAC to complete a data set on snowcover changes
in this area of intensive water resources development. Measurements have
been started of snow-covered area and snowline altitude on images of the
Mount Olympus region to obtain a longer time-series of data.
A scanning densitometer has been used at many different magnifications
and different resolution element sizes to study 70 mm ERTS transparencies
showing snowcover in small drainage basins, in order to evaluate resolution,
density contrasts at snow/no snow boundary, and accuracy of snow-covered
area measurements in presence of shadows on snow and other materials of
similar radiance (ice, firn, light-colored rock). Several other studies
of snow-mapping accuracy are continuing, as are evaluations of the several
snow identification strategies which can be used by eye or machine (i.e.,
simple density slicing, slicing on density gradients, subjective or quan-
titative identification of snow in shadows, multispectral and cluster
analysis, etc.).
Considerable additional work has been done on the measurement of ice
movement and the movement of kinematic waves of thickness or crevassing on
surging glaciers as seen on ERTS images.
Three articles on ERTS results were prepared or are in preparation.
-I
e. Discussion of significant scientific results and their relationship to
practical applications or operational problems including estimates of the
cost benefits of any significant results.
Snowlines on a small (6 km2) drainage basin were accurately identified
on bulk ERTS images without use of digital processing, and results checked
with high-altitude and ground-based photography. The area and approximate
shape of snow patches as small as 20,000 m (maximum dimension: 150 m)
could be correctly identified with a magnifying scanning densitometer
using an 80 m circular resolution element. Thus the resolution of ERTS is
more than ample for most snow mapping needs.
Down-glacier movement of a kinematic wave as part of the Tweedsmuir
Glacier surge was reported in the last progress report. Further study of
these images suggests that a zone of intense crevassing (indicated by a
darkening of the snow radiance) also spread up-glacier at a very high rate
of speed, about 200 m per day. This tentative result may be of great
importance to an understanding of surging glacier dynamics, as it apparently
shows the location where rapid movement began and how this rapid movement
spread along the length of the glacier.
Mount Baker, Washington, has a large crater south of the summit and an
area north of the summit which emit considerable geothermal heat in the form
of fumaroles and hot ground. Temperatures here are being monitored using
an ERTS Data Collection Platform. Also, debris flows are occasionally
released from the crater due to water saturation at the base of a heavy
snowpack lying on hydrothermally altered hot ground. These debris flows
present a possible hazard to life and property, as they are discharged
down the Boulder Glacier toward Baker Lake, the upper of two major hydro-
electric power reservoirs which are situated above the populated Skagit
River valley. Study of ERTS images shows that the most recent debris flow
(20-21 August 1973) can be clearly discerned and mapped. Thus ERTS images
provide another important tool for monitoring this potential hazard.
f. A listing of published articles, and/or papers, preprints, in-house
reports, abstracts of talks, that were released during the reporting
period:
Paper presented at Second Annual Symposium on Applications of Satellite
and Airplane Remote Sensing of Natural Resources in the Pacific Northwest:
Krimmel, R.M., Use of ERTS images in glacier studies.
Papers prepared for EROS book on use of ERTS images:
Post, Austin, Meier, M. F., and Mayo, L. R., Measuring the motion of
surging glaciers.
Krimmel, R.M., Post, Austin, and Meier, M. F., Monitoring surging glaciers.
Frank, David, Debris avalanches at Mount Baker volcano.
Krimmel, R. M., and Meier, M. F., Measuring snow-covered area to
predict reservoir inflow
Paper accepted for International Symposium on Remote Sensing in
Glaciology, Cambridge, England:
Krimmel, R. M., and Meier, M. F., Glacier applications of ERTS images.
g. Recommendation concerning practical changes in operations, additional
investigative effort, correlation of effort and/or results as related to
a maximum utilization of the ERTS system:
None.
h. A listing by date of any changes in Standing Order Forms:
7 November 1972
1 May 1973
i. ERTS Image Descriptor forms:
In preparation.
j. Listing by date of any changed Data Request forms submitted to Goddard
Space Flight Center/NDPF during the reporting period:
None.
k. Status of Data Collection Platforms:
N/A


Evaluate ERTS Imagery for Mapping and Detection of Changes of Snowcover on Land and on Glaciers

Abstract

Similar works

Full text

Available Versions

NASA Technical Reports Server

NASA Technical Reports Server

NASA Technical Reports Server

NASA Technical Reports Server

NASA Technical Reports Server

NASA Technical Reports Server

NASA Technical Reports Server

NASA Technical Reports Server

NASA Technical Reports Server

NASA Technical Reports Server