2007 Deployment Log

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Contents

Introduction

This content on this page was created by Logan Berner as an account of field activity over the course of summer 2007 on the SEAMONSTER project. There are some prefatory remarks and images (sites, instruments, a GIS result etc) and then we continue with Logan's narrative. Logan has made a great contribution here; his corresponding lab notes are here.


Note to other SeaMonsters: Change this intro if you wind up adding more!

Lemon Creek

The USGS has gauged Lemon Creek since 1952 (with gaps). The summary is here [1] and the 2005 hydrograph [2] (pdf) is available.

Lemon Glacier

Eran and company get the Cairn Peak met station up, May 2007

Mendenhall Terminus Moraine

Mendenhall Glacier, like all but one of the Juneau Icefield outlet glaciers, is retreating back up its confining valley. The photo below shows the terminus at an indeterminate time in the past. The red line shows the terminus in May 2007 and the blue line the terminus in June 2007.

Kayaking the terminus with a GPS unit to map summer recession of Mendenhall Glacier

Mendenhall Glacier

Pools of water--marginal lakes--collect along Mendenhall Glacier at these indicated locations. Logan is working with pilots who are frequently flying over Mendenhall to try and track when these lakes suddenly drain.

Location of marginal lakes on Mendenhall Glacier, thought to contribute to calving events by rapid drainage into the sub-glacial plumbing.

Eagle Crest (Fish Creek Watershed)

  • Tower met station
  • Snow-depth Sensor and etcetera
  • Uses a 900MHz 'black box' radio modem to push data to NSRL

Logan's Entries

Managed Mote Deployment (20070921)

On this day in history, Rob Fatland, Suzie Teerlink, and Logan Berner conducted a managed deployment of three field motes along Lemon Creek for the purpose of collecting water temperature and electroconductivity measurements during a rising tide.


Teerlink and Berner report on managed deployment of field motes


Photograph Lemon Watershed, Recover PX Sensor, Download Cairn MET Data (20070918)

On this day Eran, Rob Fatland, Andrew Whitley, Andrew Revkin, and myself flew up the Lemon watershed with Coastal Helicopters. As we flew up, Rob took photos out of an open slot on the front left window, while I opened the door on the back right and photographed the southern side of the watershed. In total we shot off somewhere around 1500 photos round trip. We landed slightly north of Cairn Peak, perhaps a 100 m from the PX transducer and were able to recover the PX sensor and data logger in short order. Andrew Revkin, a New York Times reporter, took a bunch of photos of our work and had Eran say some things into the little hand held microphone. Next we flew up to the weather station with the intent of breaking down all of the sensors, save the temp/rh; however, the pilot had a tour 15 minutes from when we landed and thus we were only able to download the data logger. The MET station thus still needs to be broken down. Additionally, the ablation stakes also need to be recovered.

Redeploy Mendenhall NetRS (20070917)

The NetRS which was originally deployed with Dr. Roman Motyka was returned to the site behind the Visitor's Center after being brought back to the lab for a few days and having the data downloaded. As it was pouring rain, the session was enabled while at the lab and the unit was simply plugged into both the power and antenna cables back at the site. The unit was not checked to ensure that it was logging; however, if the session is enabled before shutting the unit down, when the unit is powered back up the session should kick start itself and being logging. Though just to be sure the unit will be checked in the next couple of days.

Trouble Shooting MGT MET Station Datalogger (20070911)

Marijke and I went back out to the MGT MET station and tried to troubleshoot the datalogger. To start with, the datalogger was downloaded and it was determined that the logger was still not recording even after installing the 'Mendenhall.dld' program the day before. The program was sent again and the outputs were examined in real time, though only what appeared to be the battery voltage and one other number showed up. Edlog was used to create a new test program which simply consisted of a new CR10X file that was compiled. This program was sent to the datalogger and when the data stream was viewed in real time there were only zeros. The 'Mendenhall.dld' file was sent back to the datalogger the power usage of each instrument was examined. A volt meter was used to test the voltage potential between each of the wires fed into the datalogger and the 'ground earth' bolt. Only the rain gauge registered any power consumptions (Marijke has the exact numbers, but it was around 4.5V). The Temp/Rh and anemometer registered no power consumption. The following statements can be made about the status of the datalogger-

1. The datalogger is recording only one value in excess of the voltage and the rest are zeros.
2. The Temp/RH and anemometers are not being powered.
3. The logger can receive programs and can be downloaded (i.e. the serial port is functioning)
4. The power input seems sufficient from the batteries.
5. The internal battery is band new.
6. The silver portion of the datalogger has been replaced and the problem still persists.

Given these conditions, it is possible that the problem might lie somewhere on the faceplate of the datalogger. Perhaps the issue is with the 37pin connector?

GPS Mendenhall Terminus and Service MGT MET Station (20070910)

The Mendenhall Glacier terminus was remapped using a Trimble Pathfinder with the help of Suzie Teerlink's husband, Lief. A series of photographs were taken once again from near Nugget falls and will be fashioned into a panorama. It was possible this time to kayak behind the terminus on the east side and beach the kayaks just below the large waterfall with is now emerging. That area has opened up substantially since earlier this summer and it was possible to begin gps-ing perhaps 50m from the new waterfall. The waterfall was raging and it appears that the vast majority of the water was coming from subglacial sources. The water was too turbulent and the bottom too rocky to get any closer to the waterfall. The ice near the waterfall is vertical and appears quite unstable. Along the back eastern section, the lake has inundated many of what were previously isolated crevasses and it appears that this section is getting ready to go. Along the eastern 1/3 front of the glacier there is a depression which looks similar to that observed by Ellie Boyce and Dr. Roman Motyka back in 2004 prior to the massive break up. Additionally, there were a number of thermal erosion notches which appeared to extend back into the face perhaps a meter. It seems that the eastern 1/3 is going to undergo rapid recession in the near future owing to its overall unstable appearance. The central and western portions of the lacusterine-bound terminus show some recent calving activity, as is evidently be the dark blue, recently exposed ice and by the congestion of the lake with burgs. There are a fair number of long (i.e. ~ 30m) and thin (~5m) cracks which extent back upglacier, some of which were possible to kayak through. There were three sections just west of center where the ice overhung perhaps 5m. It all looked very unstable judging by the unsupported ice columns, etc. Hiking along the western edge illustrated that portion or lake are being exposed where earlier this summer the ice appeared grounded. The ice cave near the stream running off of McGinnis have totally caved in at this point, leaving behind only a narrow ice arch which is bound to break up soon. Mapping concluded where the ice cave was previously located.


After mapping, the MGT MET station was given a checkup. The datalogger was downloaded; however, once again the file lacked measurements. Thus, the silver portion of the datalogger, primed with a new internal Li battery, was replaced with one from the lab and the 'Mendenhall.dld' program was uploaded. The logger was downloaded after 15 min and no measurements had been recorded. The batteries for both the MET station and the camera were checked with the following results-

Met Station- batteries 10.23V, load 10.15V, solar 10.2V
Camera- batteries 11.71V, load 11.69V, solar 19.35V

Recover Lemon Glacier Ablation Stakes and Download Cairn MET data (20070811)

On this day in history, Marijka, Dave, Nick, Carley Lowe, and Logan flew up to Cairn Peak. Data was downloaded from the MET station (n= 63166 values on Eran's laptop) and the batteries were checked (Battery = 14.59 V, Solar Charge = 16.04 V). After the data was downloaded, Marijka, Dave, Nick and I roped up and set about locating the ablation stakes which had previously been installed atop the glacier. Using a GPS to navigate and an ice ax to probe suspicious looking cracks, we made our way to the four stakes. All of the stakes had melted completely out of the snow and were found simply lying on the snow. Each of the stakes was reGPSed using a personal Garmin eTreks before being redriven into the snow. Each of the four stakes was driven 150 cm back into the snow.

It proved somewhat challenging to drive the PVC-pipe stakes back into the snow, as in a number of places ice lenses inhibited progress. I found that if the stake was pounded into the snow, the pipe would fill with tightly packed ice, thus making it very difficult to drive it in further. It proved helpful to pull the pipe out every few attempts to drive it in further, hold it like a sword from the end, then swing it from over the head down to the ground. After a few attempts this would send the ice flinging out over the glacier. By repeatedly clearing the pipe in this manner it was possible to get most of them well situated. In two cases, it proved necessary to use the snow shovel to hammer the pipes back to the 150 cm mark.

A snow probe was used in an attempt to ascertain snow depth; however, as mentioned before, thick ice lenses inhibited probing. Only at site 1, that furthest down glacier from the lake, was it possible to probe completely to the end of the probe shaft. At site 1 probing indicated that the snow was > 3 m in depth.

After reinstalling the stakes, some time was spend exploring around the now drained Lake Lynn. This proved a good opportunity to practice some of the glacier travel and rescue skills that we had been learned back in the lab. Dave graciously volunteered to climb into a small crevasse and allow Marijka and Nick to rescue him using a Z-pulley setup. Additionally, self-arresting was also practiced. All in all the time on the glacier was quite productive and beautiful.

On a side note, we flew over Blackerbee Ridge and were able to see the trail running along the top. It would be good, at some point, to hike the trail with a GPS unit and make a shapefile. We could then load the polyline onto the handheld GPS units which we normally bring up there and thus be able to navigate the ridge if people are ever forced to hike out due to fog or other reasons.

GPS Mendenhall Terminus (20070702)

Activities and Methods

The terminus of the Mendenhall Glacier was mapped by Logan and Josh using a Trimble Pathfinder GPS unit set to log every second. This was done by kayaking to the east side of the lake and then hiking/scrambling across the ice/water margin till travel became impossible. At this point, the GPS was turned on and mapping commenced. Approximately 15m from where mapping started, a section of ice(~5m x 20x) looped back toward the waterfall that is just emerging from the glacier. It was not possible to get onto this section as it was only connected supra-lacusterinly by a thin, unstable ledge. This section was hand digitized into ArcGIS using a number of photographs as references. Along the eastern section it was possible to stay within 0-1 m of the ledge perhaps 95% of the time; however, along a section (~15m in length) close to where mapping commenced, a steep ridge forced mapping to occur ~3 m from the water/ice interface. Once back at the kayaks, the lacusterine portion was mapped with a high degree of accuracey (<1m). On the west side, the kayaks were beached and mapping commenced from the lakes edge and continued approximately 100m along the terrestrial portion of the terminus. Due to time constraints it was necessary to halt mapping at that point. A 2.5' x 17' panorama consisting of 9 photographs was made of the terminus and has been uploaded to the gallery site.

General Observations

The glacial ice along the eastern side is very fragmented by both transverse and longitudinal crevasses. Travel toward the centerline would be nearly impossible due to the degree of fragmentation. A number of pools of water, ostensibly connected with the lake, were observed at the bottom of depressions in the ice. Much of the ice along this side is heavily laiden with unconsolidated sediment which makes travel somewhat dangerous. Approximately 2/3 from the top of the previously mentioned waterfall, a subglacial stream could be seen emerging from beneath the ice and feeding perpendicularly into the main stem of the waterfall. The ice hanging parallel to the waterfall appears very unstable as it is being undercut by the stream. It should also be noted that changes in lake level could influence the amount of ice exposed on the east side and thus what is actually being mapped. Shelves of ice could be seen extending laterally underwater; however, these were not mapped as we did not want to test out the life jacekts.

The lacusterine termi showed thermal notching along its entire extent, though it appeared particularly strong approximately 1/3 the way across the terminus (e->w). In one alcove in particular, a series of three distinct, terraced thermal notches could be seen protruding out of the water to a maximum extent of about 1m. The terraced notches cut back into the ice perhaps 3m and it looked as if the whole section was getting ready to break off. Toward the western edge, the serracs appeared highly unstable and small chuncks of ice, perhaps 4cm in length, were coming off the glacier. A couple hit the kayak. Patches of deep blue ice with water seeping through pores could be seen along the western edge. All in all, it did not feel like a place to hang out for a long period of time if one values their wellbeing.

Service Lemon MET and YSI Stations (20070629)

On June 29th, Josh, Holly, Erik and Logan hiked out to the Lemon Creek MET and YSI station. Activities included-

Downloading MET data
Downloading YSI 6600 data and Calibrating Sensor
Calibrating YSI 556 and setting up sensor to run Canyon Creek for 30 min.

On both the YSI 6600 and 556 the DO, EC, and pH probes were calibrated using standards brought from the lab. The handheld YSI was placed in Canyon Creek at 13:45 and set to log each minute. While the unit was logging, Eric and Logan used the Life Book to download the MET station data and Josh and Holly calibrated and downloaded the data from the stationary YSI. The 16,928 values from the MET station were saved as 'CR1000_Lower_Lemon_MET'. The last value was logged on 20070629 @ 14:00, approximately five minutes before we arrived at the site. When we arrived, the battery lid was open and a number of puncture holes could be seen in both the lid and the main tub. It appears that a bear got friendly with the batteries again and as such it may be necessary to replace the tub. Photos of the marks were taken and have been uploaded onto the gallery site. The wire appeared to be fine and the station was opperational. The data was loaded into Excel and looked excellent. The MET station battery voltage was not tested, as we forgot to grab a volt meter.

Service Lemon MET and YSI Stations (20070621)

On June 21st, Marijke, Holly, and Logan hiked out to the Lemon Creek MET station. We left from the trail head at 9 and arrived at the site around 10:40. Data was downloaded from both the MET station and the YSI probe. The MET station appeared level and in good working order. Batteries = 13.84 V, Values Collected = 13,780, Last Data Logged = 10:45. The YSI data was named '21June07' and downloaded in the 'ascii' format. Batteries = 11.5 V, Battery Life = 115 days, Memory Avaliable = 312320 bytes, Logging = Active.

Lemon Glacier Ablation Stakes and Photographs of Lake Lynn (20070619)

On June 19th, Eran, Dave, Nick, Josh, Holly, and Logan flew up to the Lemon Glacier with Aera. Once there, Holly and Josh downloaded the data from the MET station, while Eran, Dave, and Nick installed a pressure transducer in supraglacial Lake Lynn. During this time, I installed four 150cm ablation stakes into the snow covering the glacier. The stakes were all driven 150cm into the snow and were placed roughly down the centerline. The first stake was installed approximately 100m from Lake Lynn. A number of photographs were taken of Lake Lynn and of the pressure transducer being installed.

Test NetRS on Mendenhall, EDGE, and Check North Star Base Mass Balance Site

On June 12th, 2007, Matt Heavner and Logan Berner flew up to the North Star base with Dr. Cathy Conner and the EDGE teachers. The North Star Base ablation wire installed on 5-23-07 was remeasured and GPSed, as was an older ablation wire installed during the summer of 2006. Additionally, Matt and I spoke briefly with the EDGE teachers and filled them in on some of our ongoing research. We also setup and conducted a test run of the NetRS.

Data

Old Ablation Wire

File on Pathfinder B- 'NSBOLD' (58.466072, -134.537688 WGS84)
Wire Length- 5.91 m
Notes- The wire and stand were both removed and brought back to the NSRL. A total of 50cm of wire, including the weight, were still in the ice when the stand was found. Matt believes that the station was installed May/June 2006. At this site, we spotted a wolverine approximatly 100m away and watched it watch us for a few seconds before running toward the western side of the glacier.

North Star Ablation Wire

File on Pathfinder B- NSB0712 (58.464918, -134.540067 WGS84)
Wire Length- 1.57 m
Note- The wire was not totally frozen into the hole and when Matt pulled on the wire it broke free from the ice. Subsequently, we were unable to get the wire all the way back into the hole. As a result, the new wire length is 2.36m.

NetRS

Session 'on_ice'

GPS Mendenhall Terminus and Check MET Station (20070607)

Equipment- Trimble Pathfinder B (file name- MEND0607) Dave and I spent a full day mapping out the terminus of the Mendenhall Glacier. The east side has broken up substantually since the last mapping job. What had previously looked like a tarn now is visibly an extention of the lake. Unfortunately we did not have a camera. The large waterfall nestled behind the terminus was discharging a volume of water perhaps 2/3 that of Nugget. The discharge coming through the waterfall and along the E. margin is flowing rapidly and is filled with chunks of ice. It was possible to get within, perhaps, 70-100 m of the waterfall before mapping commenced. Near the waterfall, steep, deep blue ridges were visible; sites of apparent calving. Along the E. side, it was possible to stay within 1-3 m of the lake-ice margin. In a few places steep, sediment covered ridges inhibited movement. When mapping the lacusterine portion of the terminus, the antenna was held within 1 m of the ice, except in a few cases where narrow inlets inhibited movement. Traversing east to west, the amount of ice protruding from the water increased substantually. While large iceburgs in the lake appeared to have broken off the E side, as indicated by the patterns of sediment and melt-lines on the burgs, the W side appeared to be rather unstable. Large columns of ice were ostensibly precariously balanced, just waiting to calve off. The kayaks were beached on the W bank and mapping continued on foot up to near the icefalls. The W. did not appear to have changed all that much since the last GPSing.

While on the E. side, Dave checked the National Geographic camera and reported that it had taken 417 photographs. MET Station Batteries

2x Actively Charging Batteries- 14.3 V
2x Non-Charging Batteries- 12.3 V, 12.4 V


Mendenhall Mass Balance Day 1 (20070521)

Three of the upper Mendenhall mass balance sites (Summit, Upper North, and Upper South) were visited today by Matt, Eran, Regine (UAF), and Logan. At each site, ablation wires were installed, snow pits were dug, and magnets were tracked down. Matt has the magnet data, while the snow-pit data will be posted shortly.

Summit

Coordinates of the ablation wires are saved as "SUM521" on the ENVS B Pathfinder.
Length of wire installed: ~13 m
Length of wire exposed: 1.25 m

Upper North Branch

Coordinates of the ablation wire saved as "NB521" on ENVS B Pathfinder.
Length of wire installed: ~12 m
Length of wire exposed: 1.10 m

Upper South Branch

Coordinates of the ablation wire saved as "SB521" on ENVS B Pathfinder.
Length of wire installed: ~12 m
Length of wire exposed: 0.60 m

Mendenhall Mass Balance Day 2 (20070523)

Four sites on the Mendenhall Glacier were visited today by Matt, Logan, Regine, Liza, and Marta. We departed from N. Star at 9:30, spent approximately 1.5hrs at each site, and returned at 16:30. The four sites included the lower north branch, lower south branch, flux gate, and North Star base. An ablation wire was installed at each site, while snowpits were dug only at the lower north and flux gate sites.

Lower North Branch

Coordinates of the ablation wire saved as "NB2523" on ENVS B Pathfinder.
Length of wire installed: 10 m
Length of wire exposed: -0.2 m (Note: the hole was deeper than the wire was long, thus snow was removed and the tetrahedron was placed slightly below the surface. The wire starts 0.20 m beneath the surface.
Snow Depth: 5 m (As determined by probing the bottom of the snow pit)

Lower South Branch

Coordinates of the ablation wire saved as "SB20523" on ENVS B Pathfinder.
Length of wire installed: 10 m
Length of wire exposed: 1.0 m
Snow Depth: 3.75-3.80 m (As determined by probing)
Note: Avalanche probe found a very hard layer at 3.75 m, though Matt broke through at one point. Check to see is this spot was snow-covered last year. Matt's eTrex GPS point: (WGS84) 58 30'50.8", -134 29'04.5,3323 ft.

Center Line Flux Gate

Coordinates of the ablation wire saved as "CLFG0523" on ENVS B Pathfinder.
Length of wire installed: ~12 m
Length of wire exposed: 1.2 m
Snow Depth: 4.6 m (As determined by probing the bottom of the snow pit)

North Star Base

Coordinates of the ablation wire saved as "NSB0523" on ENVS B Pathfinder.
Length of wire installed: 5.3 m
Length of wire exposed: 0.95 m
Snow Depth: 0.55 m

Service Mendenhall Terminus MET Station (20070518)

Service Lemon Creek MET and YSI Stations (20070516)

Map Terminus of Mendenhall Glacier (20070512)

The terminus of the Mendenhall Glacier was mapped using a Trimble Pathfinder (ENVS Pathfinder B). Kayaks were rented from the UAS Rec center and launched at the USFS Visitor's Center. Laurie Craig, USFS Project Leader, let Carley and I barrow two USFS radios for emergency purposes, though these radios were ultimately not used. It took approximately 40 min to kayak to the east side of the terminus. It was possible to hike approximately 200m along the ice margin before the route became impassible. On the east side, the glacier has retreated laterally away from the base of Mt. Bullard, leaving a small, marginal lake that is connected to Mendenhall Lake via a small stream and most likely subglacially. Once hiking became impossible, the Pathfinder was turned on and mapping began (file name = MEND0512). Along this side, 3-4 satellites were routinely acquired, though connection was occasionally lost where the ice-cliffs were large. The GPS receiver was held as close as possible to the edge of the glacier (normally with in 1-2 m).
The GPS was paused before reentering the kayak and getting situated to GPS the lacusterine portion of the terminus. The GPS receiver was held approximately 1 m from the terminus while kayaking, though there were a few places where narrow, vertical cracks inhibited kayaking near the terminus. The amount of ice protruding out of the water increased E-->W and approximately 2/3 across the lake the terminus became very steep and appeared to have recently calved. There were a fair number of large icebergs floating in the lake.
The kayaks were beached on the west side of the lake and mapping continued from the waters edge along the land-ice margin. It was possible to hike all the way to the bottom of the icefalls. The receiver was held within 1 m of the ice during this portion of the treck.
The data was downloaded using GPS Pathfinder Office software (Utilities--> Data Transfer). The GPS had been set to create a bread crumb trail and thus it was necessary to convert the points into a continuous line (Utilities--> Grouping). The data was then exported as an ArcView Shapefile (Utilities--> Export). This file was exported with a generic name which specified the feature type. This file was loaded into ArcGIS 9.2, where, for some reason, it was once again a series of points. Hawth's Tools was used to create a continuous line from the series of points. This shapefile was merged with another shapefile which some UAS students (Peter Flynn and Adrien March)had created after mapping the terminus back in March. The files merged file is named: Mendenhall_Terminus_Compilation. The file is currently saved on my thumb drive, though will be uploaded to the mainframe.

Install Mendenhall Terminus MET Station (20070509)

Install Cairin Peak MET Station (20070504)

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