Taking the Pulse of Petermann Gletscher

Posted by Pat Ryan for Andreas Muenchow

23-August-2015 at 80:57.3 N 061:27.1 W

(note correction below)

I just may have made a discovery that I cannot share with anyone on the ship right now. The giant mass of ice that is Petermann Gletscher just slowed down moving only 1 meter per day for the last 3 days rather than the 3 meters per day that it usually does and that has been reported in the scientific literature. This measurement comes from the newly deployed University of Delaware weather station that also contains a not-so-fancy $300 Garmin GPS as well as 5 ocean sensors that measure temperature and salinity about 95-m, 115-m, 300-m, 400-m, and 810-m below the surface of the floating and moving ice.

Time Series of Glacier Drift

Time Series of Glacier Drift (correction appears below)

As the glacier puts on the breaks, I also see a rather dramatic increase in ocean temperature from -0.6 to -0.35 degrees Celsius within about 10-m of the ice-ocean interface. The saltiness of the ocean also increased from below 34.1 to above 34.2 practical salinity units that you can think of as grams of salt per kilogram of water, roughly. Only 20 m below in the water column, the opposite is happening: The water there cools a little bit and becomes fresher. This suggests some mixing as the salinity differences become smaller and heat from the lower layer moves up towards the ice. Some force must be applied to the fluid to do this. Recall that a force is mass times acceleration. The force of a mosquito splashing on the wind shield of your car is small, because the mass of the mosquito is small even though its acceleration (from zero to the speed of your car) is large. Now imaging this glacier: Its mass is enormous, so you only need to change its velocity a tiny amount, from 3 to 1 meter per day, say, to generate a massive amount of force.

Photo of helicopter deck with Belgrave (left) and Petermann (right) Glaciers in back Aug.-23, 2015; view is to the north-east.

Photo of helicopter deck with Belgrave (left) and Petermann (right) Glaciers in back Aug.-23, 2015; view is to the north-east.

As I look outside my cabin window right now, I see the terminus of Petermann sitting there innocently not appearing to do much, but it is literally changing the face of the earth as it moves fast, slows down, moves some more, and over 1000s of years cut a very deep fjord and perhaps canyon deep into the mountains and even deeper into the sea floor. The helicopters are whizzing overhead right now returning all the gear that was needed to drill through 100s of meters of hard glacier ice to provide access holes to both ocean and sediments that has been in total darkness for many 100s of years.

Photo of helicopter delivering cargo from the finished ice camp back to the ship on 23 Aug. 2015.

Photo of helicopter delivering cargo from the finished ice camp back to the ship on 23 Aug. 2015.

Still, there is life down there, lots of it Anne Jennings, who closely looks at the sediment cores, tells me. We speculate that the life is supported by vigorous ocean flow that connects the open fjord with the glacier covered deep ocean. Food stuff like plankton may move some distance under the floating glacier to support a population of other critters that I know nothing about. No narwhals this year so far, though.

So why I am writing this up here rather than share it with people on the ship? Well, this is Sunday morning and there was much to celebrate last night when the ice drilling team returned after 2 weeks camping on the ice and collecting data from their three drill holes. Furthermore, the the ocean weather station reported for the first time in over 2 days uploading all the data I show above. This happened well past midnight and several of us discussed the data and future plans in the cafeteria until 1:30 am. So the people not working right now are all sleeping (10:30 am here) as we probably will work through the night to map the Atlantic waters flowing into the fjord at its sill towards Nares Strait …  which we have not yet done over the 3 weeks we have been in the area. I probably also should help with unloading the helicopters or getting the Chief Scientist Alan the data files he needs to catalogue the water samples we collected last night. Work on Oden never stops … as there is so much to do as we are barely scratching the surface or bottom of the ocean here. [Incoming helicopter, 4th one since I wrote these lines too fast, perhaps.]

Screenshot of a successful RS-232 serial connection from ship to ocean weather station on Petermann Gletscher and ocean sensors deployed 810 m below the glacier’s ice surface with active real time data transmissions. This session uploaded new codes to the secondary data logger to activates its secondary back-up memory.

Screenshot of a successful RS-232 serial connection from ship to ocean weather station on Petermann Gletscher and ocean sensors deployed 810 m below the glacier’s ice surface with active real time data transmissions. This session uploaded new codes to the secondary data logger to activates its secondary back-up memory.

Correction:

Petermann Gletscher did slow down the last few days by about 10% as measured by the GPS at the UDel ocean-weather station. The suggested slow-down to 300 meters per year, however, is false, because I did not properly take into account how the station was moved by 30 meters to the south-west. The correct and updated estimate is the figure below. Please discard the the above figure erroneous.

Sorry for the confusion … more data coming from this station will place the short term change in glacier speeds into a larger context. Furthermore, the present “cheap” GPS system will need to be verified by a set of three “fancy” differential UNAVCO GPS that were recovered today, but we have not yet decoded the data contained on those units.

Back to CTD profiling the water properties across the sill at the entrance to Petermann Fjord that we will have to complete by 3 am or in about 6 hours.

Time Series of Glacier Drift (Corrected)

Time Series of Glacier Drift (Corrected)

Ocean Observing Station Reporting from Below Petermann Gletscher, Greenland

We discovered warm waters 800 meter down a hole drilled 100 m through Petermann Gletscher ice.  Every hour an ocean sensor querries temperature, salinity, and pressure and reports its readings to a weather station atop the glacier. The warm waters come from the Atlantic and enter the Arctic Ocean near Spitsbergen. Prior to hitting our sensors in an 800 m deep fjord in northern Greenland, the water moved along Siberia, Alaska, and northern Canada before snaking its way into Petermann, Greenland to perhaps melt this glacier from below while surface air temperatures are already below freezing. It is a long way from home for both those Atlantic waters and us scientists and crew here aboard the Swedish icebreaker Oden and four hardy explorers camping on the floating ice of Petermann Gletscher.

Peter Washam on Petermann Gletscher at an ice drilling camp. Cables and ropes against tent are used later to connect ocean sensors to the weather station.

Peter Washam on Petermann Gletscher at an ice drilling camp. Cables and ropes against tent are used later to connect ocean sensors to the weather station.

Keith, Paul, and Mike of the British Antarctic Survey as well as my graduate student Peter deployed 5 ocean sensors with cables and ropes. A weather station designed by David Huntley of the University of Delaware provides the command and control between ocean sensors, battery and solar panels, and the Iridium satellite modem to send data back home. For me this engineering project took over much of my life the last 6 months as all testing and coding has been done while traveling. Much problem-based learning took place not for pedagogic reasons, but as a necessity to make something special work. And work it does.

First 14 hours of ocean data from below the floating ice shelf of Petermann Gletscher as of 20. Aug. 2015. Top time series are from just under the ice shelf near 120 m while the bottom time series is from a sensor at 810 m below the surface.

First 14 hours of ocean data from below the floating ice shelf of Petermann Gletscher as of 20. Aug. 2015. Top time series are from just under the ice shelf near 120 m while the bottom time series is from a sensor at 810 m below the surface.

These are the first and only data from below a glacier in Greenland that do not involve a person tending to instruments, computers, and cables with a helicopter or aircraft waiting. Our observing system is fully automated and the first 14 hours of data were collected by my computer on the ship calling the computer on the weather station which then sends the data after some computer-to-computer hand-shaking.

The weakest and most fickle link in this chain is the Iridium satellite phone to move data through thin and cold air. Senator McCain of Arizona called the ship yesterday and was rudely disconnected by Iridium the same way that our ocean weather station is.

Rob Holden testing Iridium phones above the bridge of I/B Oden.

Rob Holden testing Iridium phones above the bridge of I/B Oden.

Unlike busy, engaged, and well-meaning politicians, however, the computers will tirelessly try again and again every three hours to send the data back that the weather station on Greenland accumulates no matter how well Iridium is connecting it to us.

Power is key as is a flexible budget that adapts to both scientific needs and environmental conditions. I here do not talk about politics in Washington, DC, but the design of the weather station that is powered by both batteries and solar panels while the Iridium modem is the most energy gobbling component of the ocean observing system. Hence it is switched off at all times except a 20 minute window every three hours. I will have to change this window to 20 minutes once per day in the winter when the station will have to operate in complete darkness. So, many challenges are still ahead which includes a mechanical design to fix a weather station on a melting glacier, but alas, winter here is already upon as with air temperatures on and off the glacier below freezing. New ice forms in the early morning hours already.

Terminus of Petermann Gletscher with Hubert (right), Belgrave (center), and Un-Named (left) Glaciers coming in from Hall Land in the north. The ocean is to the left (west).

Terminus of Petermann Gletscher with Hubert (right), Belgrave (center), and Un-Named (left) Glaciers coming in from Hall Land in the north. The ocean is to the left (west).

Sent from I/B Oden at 17:38 UTC on 20 Aug. 2015 at 81:26 N and 064:03 W

A roller coaster ride in the Arctic

Posted by Pat Ryan, Graduate Student (Thursday, August 13, 2015)

It’s been a busy week.  The events that transpired during and since the initial installation of the weather station on Petermann Glacier gave us some ups and some downs (therein the roller coaster).  I’ve shared below (in italics) some of the emails that document the saga as it unfolded.

On Monday morning, we heard from Andreas:

I just got back after 12 hours working on Petermann Gletscher where I was given a helicopter for the day to accomplish the following:

1. Deploy very fancy sub-centimeter GPS receivers we got from UNAVCO (Peter of UDel);
2. Find a suitable site to place the Udel weather station with their 5 ocean sensors attached (Keith Nicholls of BAS);
3. Deploy the Udel weather station prior to the ice shelf drilling (I did this).

Less glamorous, I spent most of the day in packing and moving boxes while two helicopters were buzzing overhead coming and going as the first drill site was moved to a second drill site. At the end of the day, however, our weather station went up. It was not a pretty job as we had only an hour left before we had to be back on the ship, but the weather station is now sited and returns data on a regular schedule. It does work. 

Helicopter transport of instruments via sling load.

Helicopter transport of instruments via sling load.

Here is a picture that shows the station’s current installation at site-3  which is temporary as Andreas will modify the mounting design after 5 ocean sensors are attached to it early next week. The shown design would not survive strong winter winds and excessive surface melting in the summer.

University of Delaware automated weather station on Petermann Gletscher (view to north-east).

University of Delaware automated weather station on Petermann Gletscher (view to north-east).

On Tuesday, our spirits were somewhat crushed when Andreas informed us that he had heard nothing from the station for 5 hours. As it was scheduled to automatically send data on an hourly basis, this was somewhat disappointing. Both Andreas (from the ship) and I (at home) attempted to manually connect to the station.  Neither of us was successful.  We all waited somewhat impatiently to hear from the station. Andreas was hopeful that he could get back to the site in order to diagnose and repair any problems that had arisen.

This morning (Thursday) I woke up to the following delightful email from Andreas. The subject line is Greeland Weather Station Working!!!

Hi all:

I am ecstatic to report that our weather station on Petermann Gletscher is alive collecting and reporting data. The earlier shut-down, 8-hours after deployment on Aug.-10, was caused by Iridium satellite transmissions, not the set-up of hardware or software of the weather station itself. I attach a plot of the data collected so far that is being used by the ship’s operators to prepare and plan for flight operations over the glacier. There will be a massive increase in helicopter flying, because on Saturday the CBS 60-Minute team will arrive via helicopter from Qaanaaq, Greenland about 250 miles to the south.

The five ocean sensors are NOT yet plugged into the UDel observing system, because ice-drilling operations at that site will not start until Monday or Tuesday. Our graduate student Peter Washam is on the glacier right now. The so-called Ice-Shelf team just completed a second drill hole near the grounding line of Petermann Gletscher where ice and water are expected to be as thick as the Empire State Building is tall. The picture shows Peter at that (second) drill site shortly after the camp there was established there Monday. The weather station was set-up about 13 km seaward  at what will become the third drill site. Hopefully he did not forget to re-program the ocean sensors to move bits and bytes along the 600 m long serial cable (4800 baud) at a slower rate than we used them in an calibration test lowering them from the ship to the 600 m deep bottom of the ocean near Petermann Fjord.

AWS-Aug13

The 2 1/2 day long time series (link above) shows air temperature about 0.5 and 2.0 m above the ice as well as wind speed and direction as well as atmospheric pressure. A GPS unit shows that the station is drifting about 3 m per day towards the ocean as is expected for this fast moving glacier moving about 1.2 km per year.

My spirits are high after several days of anxious anticipation and waiting for a call from the weather station. Wish us luck.

Andreas (aboard I/B Oden at 81 32.28′ N 062 04.0′ W on 09:49 UTC)

Since the iridium system is designed to gather data until it can be successfully transmitted, short periods of communication black-outs are not expected to be a problem.  The data storage is limited, so we are hopeful that the communication failure was temporary and any future lapses will be equally short-lived.

We soon should have have ocean data of salinity and temperature conditions under the glacier when the additional instruments have been lowered through the ice next week.  That will be the story of our next post.

Preparations and Installations

Guest Blogger:  Pat Ryan, graduate student

Field research can be described as exciting, challenging and demanding. The work, especially when undertaken in the Arctic, has proven to be all of these to me. Planning ahead is an important part of the task. Since we are so far removed from things like high speed internet connections and hardware stores, we try to be as prepared as possible with redundant equipment, any computer data file and programs we  anticipate that we might need, a set of backup plans for foreseeable contingencies and a toolbox full of gizmos and gadgets which might come in handy to solve the inevitable complications that will arise. It seems to me that the most important skills for an Arctic researcher are perseverance, an inclination to be very creative and a good sense of humor.  The scenery, however, can be breathtaking.

Belgrave Glacier

Belgrave Glacier

This summer, I’m the stay-at-home scientist. Whilst my advisor Andreas and my fellow graduate student Peter are working in Petermann Fjord, I’m home and am attempting to help as much as I can from here. This assistance has included installing a satellite communication system here and testing these systems that we’ll be using to transmit data about ocean conditions under a glacier and atmospheric conditions above it to us in Delaware for as long as we can.

In accomplishing this project, the phrase, “it takes a village” comes to mind. Weeks ago, David Huntley of the Delaware Environmental Observing System (DEOS) at the University of Delaware configured the meteorologic station that will be the communications hub for all our data. He also trained us on installation.  This hardware was packed up and transported to a ship, the Oden, in Sweden to be carried aboard for this summer’s research cruise to Petermann Fjord.   Last week, on the Oden in the Arctic, Andreas configured the data gathering and transmission equipment, utilizing creative wiring techniques to allow regular transmission of data via satellite communications systems.  Unfortunately there are no cell towers here either so satellite phones are being used to send the data.  At home, I installed hardware to receive the data.  Throughout this process,  Kevin Brinson, Director of DEOS, used his experience to provide consultation and guidance on all of this, including acting as a liaison with high-tech equipment manufacturers. After several days of work to implement this near-real-time monitoring system to measure conditions and transmit those measurements within hours of their capture, we have a working system!

The exhilaration we all felt upon the first successful connection and seeing information like the ambient temperature and barometric pressure at Petermann Fjord (measured less than an hour before I got it) made all that work worthwhile. Upon installation of the monitoring station on the surface of the glacier and drilling through the ice to place ocean measurement instruments, we should have a system that can give us this and much more information for an extended deployment – perhaps several years – and return that data every day.  The last time we installed this kind of ocean monitoring instruments, they measured for 3 years and required us to to return via ship to recover the instruments before we got any data.

How long these instruments will collect data is dependent on a number of factors. Conditions in the Arctic can be rather rough on electronics. Temperatures dip below -40 degrees (either Celsius or Fahrenheit) and polar bears are very inquisitive creatures – wires seem to attract their curiosity.   The ice upon which our equipment will rest has been melting. Eventually, this glacier will calve and the location of our monitoring station is likely to be impacted by melting and/or calving (or breaking off) of the glacier.   Our equipment is battery powered with solar charging supplements when there is sunlight. We hope that our batteries will be able to give us data throughout the long Arctic night that will last for months until sunrise (when solar charging begins again) in the spring.

Meterologic station aboard the Oden.

Meterologic station aboard the Oden.

Meterologic station aboard the ship.  The ice of Greenland in the background.

Meterologic station aboard the ship. The ice of Greenland in the background.

Tomorrow, Andreas and Peter will be venturing out to the ice in the first steps of installing all this hardware. We are very excited about the prospect of seeing the results of many months worth of planning and work.  As the project continues Andreas and Peter will keep us up to date on their progress.

GPS, Geocaching, and Greenland Glaciers

Navigating ice, ocean, and land, brave women and men have always used the stars for guidance. Just think of the three kings who followed a star to witness the birth of Jesus Christ in Bethlehem 2015 years ago. They were 6 days late. Keeping track of time track was always difficult for navigating, especially at sea and the British Navy lost many ships as a result of poor time keeping. There are books written on the history of determining longitude, the best of which is called, well, “Longitude.” Now why would I ponder these questions and histories two hours before I am boarding the Swedish icebreaker Oden to travel by sea and ice to Petermann Glacier?

The Global Position System (GPS) that many of us have in our smart phones or tiny hand-held devices makes navigating easy. Both measure time as our civilization has put “stars” into space that guide hikers out in the back-country, urban dwellers to the next bar or restaurant, and missiles into a target the size of the dot over the letter “i” on a license plate of a car. Few know that the GPS satellites only sent time from an atomic clock to our GPS receivers and smart phones. Time is of the essence, there is something almost spiritual about time and how to define it. And time is linked to space not just because of Einstein’s theory of relativity, but also the way we measure space by measuring the time that waves travel through space.

Waiting for the plane to get 58 scientists to Thule to board the I/B Oden, I went for a geocaching trip an hour or two from the town of Kangerlussuaq. My wife got me into this 2 years ago as a way to explore areas via hiking without much planning. All we do is enter some GPS position of places where other people have placed “treasures” and we head out to find them. These geocaches are everywhere: within 100 feet of my home, in every city I went to in Poland, Sweden, or Germany, and now Greenland, too. My favorite GPS unit is a little hand-held $99 Garmin eTrex 10. It does a marvelous job to get me anywhere within about 3-6 feet (1-2 meters).

As part of our Petermann research, we also got four “fancy” GPS systems which we want to place on the ice shelf of Petermann Gletscher to measure tidal motions. The water under the glacier is connected to ocean that moves the Empire-State-Building thick ice up and down every 12 hours or so. We do not know by how much, though, and when it moves up and when it moves down. There should also be daily cycles and longer periods caused by winds and waves. Now these fancy $25,000 GPS are able to track over 400 satellites (not just the 9 that my Garmin does) and they receive the time information in a very raw and accurate format at more than one radio frequency in more than one way. If one has several of these, we got four, then it is possible to built a network that reduces common errors in position to a few millimeters in the horizontal, and 1-2 centimeter in the vertical after some smart processing. So these “fancy GPS” can sense the difference of the top of your smart phone from the bottom, and I do not mean its length or width, but its thin height. And this is blowing my mind. We need this accuracy to measure tides, and tides we will measure for the 20-30 days that we are working in and around Petermann Gletscher.

Wish us luck as we are heading from the green part of Greenland in the south to its white (ice), black (ocean), and gray (land) parts. There are few colors where we will be the next 4 weeks. Our internet will be gone, but I will try to send text files and small photos until we return on 4 September or so, but time will be hard to find. Wish all of us luck …