Spring Field Work

My work during the spring field season with the Norwegian Polar Institute started in Longyearbyen in mid-April.  After waiting a few days, Dr. Kohler and I departed for Kapp Linné to do a mass balance study on Linnébreen.  We snow mobiled from Longyearbyen to Isfjorden Radio, a trip of around 100 km.  Isfjorden radio used to be the main point of contact between Svalbard and mainland Norway and still has a variety of antennas.  Now it serves as a tourist destination serving excellent food and offering a place to stay and an otherwise uninhabited area.  During our trip there and during the first day of field work weather was excellent and we were able to take GPS velocity measurements, stake measurements, density measurement, snow soundings, and drill one new mass balance stake.  The second day the weather deteriorated and we took some more snow soundings, density measurements, and collected one snow sample to analyze for pollutants.  Though the weather on the trip back was now as good and visibility was at times quite poor, with the aid of handheld GPS units we were able to make it back to Longyearbyen without incident.   After repacking our gear and stowing the snow sample in a freezer, we headed to Ny-Ålesund the next day. 

 

After one day of preparation in Ny-Ålesund, we planned to head to Kongsvegen, a larger glacier located at the end of the fjord.  Due to the fact that there was no sea ice this year, which although unusual is not unprecedented, we had to drive a somewhat circumspect room over another glacier and through a pass to approach the glacier on the other side of a peninsula where it can be accessed via land.  When leaving that morning it was raining, something unusual for late-April weather in Ny-Ålesund, but the snow conditions seemed passable so we pressed on.  On the other side of the pass, the entire drainage delta of another glacier had turned to slush making it very difficult to drive and we were forced to turn back after one of the most experienced drivers on a very powerful snow mobile said that he didn’t think that it was prudent to continue.  During our drive there, the snow conditions on the pass had deteriorated.  We had a lot of difficulty getting the snow mobiles and equipment back up the pass.  One snow mobile couldn’t even make it up the pass without a sled and had to be driven around the peninsula.  After returning, we were forced to reconsider our field plans and realized that the trips to the large glaciers of Holtedalfonna and Kongsvegen would have to be limited to the essential measurements, namely mass balance, unless cold weather returned.

The next few days I spend working on Midre Lovénbreen on a variety of different projects including borehole logging, ground-penetrating radar, ice coring and mass balance.  When borehole logging we used neutron probe to measure density and compared it to the bulk density of an ice core drilled in the same core or nearby.  The neutron probe contains a radioactive source which sends out neutrons.  They scatter off water inclusions in the ice and the number returned indicates the density.  I didn’t directly operate any of the borehole logging equipment but it was interesting to watch.  For the first time I did help extract an ice core.  We drilled to approximately 7 meters to compare with the borehole logging that was done in a smaller hole nearby and then logged the drill hole as well.  The drilling was a new part of field work and it was interesting to operate the drill as there is some technique to make sure that the drill bites but doesn’t get stuck.  You don’t want to have to dig it out when it is 20 feet into the ice.  We also operated radar systems in the area where we conducted borehole logging experiments and extracted ice cores.  This allows us to get some spatial coverage of glacier structure instead of only knowing the properties at one point. 

Eventually, the cold weather did return and was accompanied by a snowstorm.  The next day a group immediately went to Kongsvegen to conduct experiments and was successful in conducting borehole logging, shallow ice coring, mass balance measurement, and snow sample collection.  Although this was not the experiments were conducted to the same extent as originally planned, this was valuable data and gave people something.  Following this trip we continued mass balance measurements on Midre Lovénbreen and Austre Brøggerbreen which are two glaciers that are very close to Ny-Ålesund.  Due to the warm temperatures both in April and January we suspected that water had percolated through the snow pack and refrozen forming what is called superimposed ice.  The superimposed ice has a positive effect on the mass balance but it is difficult to measure due to the fact that you can’t easily tell the difference between superimposed ice and the glacier surface when snow sounding.  Therefore we took very shallow ice cores drilled by hand at various points on the glacier to characterize superimposed ice accumulation.  The variation from superimposed ice to the previous summer glacier surface is shown by a dirt layer followed by ice that has a different texture when we examine the shallow core.  Taking these measurements revealed superimposed ice accumulation of up to 20 cm.  This was a very large accumulation and it is easy to see how superimposed ice can play a significant role in mass balance.  After one more abortive attempt to reach Holtedalfonna in my 3^rd week in the field it was clear that it was no longer possible.  Another period of above freezing temps, which normally first come in early June and not mid-May, made it clear that it would no longer be possible to reach the glacier.  Therefore I was not able to collect additional radar data for my research on the firn lake on Holtedalfonna.  Nevertheless the field season was an excellent experience which allowed me to see many new aspects of glaciological experience and to gain important experience operating in the field. 

 Enjoy all the pictures below. 

 Isfjorden radio on a stormy day.  Notice the large number of antennas still presnet.

A density pit on Linnébreen.  Snow samples are taken vertically and weighed to measure density. 

 Jack Kohler surveys Kjell Arild’s snow moblie which sunk in the slush.  (Photo: Rune Storvold).

Borehole logging on Midre Lovénbreen.  The tent protects the sensitive electronics. 

High frequency radar experiments on Midre Lovénbreen.  (Photo: Bob Hawley)

Me operating the ice drill on Midre Lovénbreen.  (Photo: Bob Hawley)

The GSSI ground-penetrating radar field computer. 

The GSSI ground-penetrating radar 900 Mhz antenna.

Me drilling by hand for superimposed ice.  (Photo: Elisabeth Isaksson)

A very shallow ice core showing superimposed ice as the denser ice at the bottom of the core.  A dirt layer clearly marks the boundary between the superimposed ice and glacier ice from the previous summer surface.   

The calving front of Kronebreen, the fastest moving glacier on Svalbard.

Austre Brøggerbreen from a distance showing a large meltwater stream in the middle of the photograph which we had to cross on snow mobiles.

Ny-Ålesund Mass Balance Fieldwork September 2005

In late-September I accompanied Dr. Jack Kohler of the Norwegian Polar Institute to Ny-Ålesund, Svalbard to participate in the fall mass balance studies.  Ny-Ålesund is in a beautiful natural setting, surrounding by mountains and glaciers.  This is a small scientific community that has between 20 and 100 inhabitants depending on what projects are in progress.  The community is of an international nature and includes instruments or stations from Norway, Germany, France, Great Britain, China, and Japan.  For a field station, Ny-Ålesund is extremely well equipped, including: high speed internet, a solarium, gymnasium, and extensive DVD library, as well as a bar that is open on Saturday nights.  There is also a store that opens twice a week, even if it only sells souvenirs, beer, and soda.  You get to know people quickly in this small community as all meals are shared. 

            My stay in Ny-Ålesund was short, just over a week.  The goal was to complete fall mass balance studies of four glaciers in the area: Midtre Lovenbreen, Kongsvegen, Holtedalfonna, and Brøggerbreen.  Mass balance is a simple way to keep track of whether a glacier is growing or shrinking.  A brief introduction into this technique is quite illuminating and shows how simple scientific measurements can give an important result.  Generally, glaciers can generally be divided into two zones, an ablation zone and accumulation zone.  In the accumulation zone snowfall exceeds melting and there is a net gain of snow and therefore mass.  In the ablation zone melting exceeds snowfall and therefore there is a net loss of snow and mass.  If the rate of melting in the ablation zone exceeds the rate of accumulation in the accumulation zone the glacier is shrinking and recedes.  If the opposite occurs the glacier grows and advances.  In order figure out whether the glacier is growing or shrinking we place stakes on glacier and measure the distance from the top of the stake to the ice surface twice a year.  That way we can develop a time series for the change of the ice surface at each stake.  Averaging all these changes together we can see if the glacier experiences a net loss of gain in mass.  Additionally, with the advent of GPS, we can locate these stakes extremely accurately and get an idea of how the glacier flows and calculate stress and strain rates in the glacier on a biannual basis.  We also measure the meteorological conditions on the glaciers from a network of weather stations, which are downloaded when we measure mass balance each spring and fall.  Finally, we compare these results to aerial photographs and satellite images which offer another confirmation of our results.  The mass balance records of Midtre Lovenbreen and Brøggerbreen are the oldest in the Arctic going back to the late 1960s.  They thus provide us with the longest existing record of how the glaciers react to changes in temperature.  It was exciting to be part of this legacy and continue to make these measurements. 

            Working in the vicinity of Ny-Ålesund is also a lot of fun.  Our daily routine consisted of gathering our equipment: ropes, crampons, rifle, radios, precision GPS, ruler, etc., and accessing the weather for the feasibility of a helicopter flight to the further away glaciers of Holtedalfonna and Kongsvegen.  It was quite cold for September and there was already a thick snow cover but not quite enough for snow mobiles.  On the first day we hiked on foot and quickly found that this was strenuous in the deep snow and not the best way to do things.  So from then on we used skis.  Having only a basic knowledge of cross-country skiing this was a steep learning curve for me.  I have since purchased a set of randonee skis which allow me to capitalize on my more extensive downhill experience.  Once on the glacier we go to each stake, measure the position with the GPS antenna, measure the amount of snow, and measure the distance to the ice surface with a ruler.   We compare our measurements to last year’s results while in the field to make sure there are no hugely unreasonable measurements.  If necessary we also repeat measurements on site to confirm our results.  Then each night, Dr. Kohler would do a preliminary mass balance calculation to see if results seemed reasonable and to determine if we needed to repeat measurements. 

            For me this was quite a bit of fun.  I got to ski around glaciers and admire nature for a week.  The helicopter rides were especially breathtaking and offered an awesome view.  Although my interest in studying glaciers is intrinsic and related to understanding their important and not completely understood role in affecting our climate, the opportunity to work outdoors in pristine areas is a nice bonus.  I won’t enjoy working permanently in a lab nearly as much as I have always had a love for the outdoors and although some people would call me crazy, for snow and ice.  Being surrounded by mountains covered in snow and ice while making contributions to an important scientific result confirmed that I wanted to make this into my career.  I look forward to the fieldwork in the spring where I will get to spend a month in this area and help on a variety of projects including: ice-penetrating radar, shallow ice coring, mass balance, and digging snow pits.  Enjoy the pictures below of the fabulous nature surrounding Ny-Ålesund. 

Click on the photo thumbnail for a larger version of the picture. 

Midtre Lovenbreen. 

Skiing on glaciers. 

An outlet glacier of Holtedalfonna.

Fieldwork with the helicopter.

Meteorology Fieldwork September 2005

On September 1st, we received out first accumulating snowfall at sea level in Longyearbyen and the next week my Polar Meteorology and Climate class started fall fieldwork.  All courses at UNIS include a fieldwork component and unless weather conditions are dire, we spend a lot of it outdoors.  The 10 days of meteorology fieldwork coincided with the first cold air of the season, temperatures between 0 and -10°C and wind-chills around -20°C.  Although not cold for Svalbard, it does take some time to adjust.  Luckily we returned to the heated and well-equipped dormitories in Nybyen each evening so were only in the cold for 12-16 hours a day. 

Despite the cold this was an exciting experience for me.  My previous research experience has been using ground penetrating radar to image the interior of alpine glaciers and ice sheets with the St. Olaf Center for Geophysical Studies of Ice and Climate headed by Dr. Robert Jacobel.  Thus the instruments, analysis, methodology and principles were all new to me and it was exciting to be in action collecting data so soon after coming to Svalbard. 

My responsibility was the maintenance, operation, and analysis of data from a sonic anemometer.  Basically this instrument measures deviation in the speed of a sound wave between two probes from the speed of a sound wave in dry air.  This instrument has an extremely high sampling frequency and measures in three dimensions.  These properties make it ideal to examine turbulence which is of great important in boundary layer meteorology and can have a large impact on aircraft, windmills, and skyscrapers.   Understanding the turbulence in the boundary layer is also vital to understanding the thermodynamics near the earth’s surface and thus the daily diurnal variations in temperature that are standard in the middle-latitude regions that most of us call home.  The Polar Regions are unique in that this diurnal variation vanishes during times of midnight sun and polar night.  However, during this time, in early September, there are strong diurnal variations in turbulent fluxes, and thus our results were comparable to those in textbooks written about middle-latitudes. 

In order to take meteorological measurement without interference from the ground you have to elevate the instruments above other objects on the ground to eliminate interference.  We do this by using masts and measuring at several levels on the masts so we get an idea of how meteorological parameters vary with height.  It is quite difficult to raise a 10 meter mast in winds of 20-25 m/s (around 50 mph) and prompts numerous quotations that are quite amusing in retrospect, such as:

“Pull harder.  Don’t let the mast fall; we don’t want to destroy the instruments.” 

“What about the students who are below the mast?” 

“The instruments are quite expensive, and students are disposable.  I mean we receive new students every year.”

“I need good ideas; very fast…my fingers are getting quite cold.”

“So what’s the best way to fasten the guide ropes again?” 

“I am not really sure.  I just make some loops until it looks like it won’t come undone, so they don’t really have to be that good.” 

“But make sure you’re knots are good enough, we don’t want the mast to fall.” 

“We need rocks.  Lots of big rocks.” 

In addition to the large mast we also set up several smaller, 3 meter, masts in the area of Adventdalen, Svalbard to get a spatial picture of boundary layer.  The masts were set up at a variety of elevations ranging from sea level to over 1000 meters in elevation.  We also took manual observations every 3 hours in order to have a secondary record.  Finally we archived the satellite images and analyses from the days we were in the field so we would have an idea of both the local and synoptic meteorological situation. 

In order to take measurements above 1000 meters, we planned to take a series of balloon profiles up to 1 km.  We quickly learned that there were numerous frustrations with fieldwork through our experience with the balloon.  First in order to launch the balloon winds had to be below 10 m/s (20 mph), otherwise we risked loosing the balloon and tether system and we couldn’t risk damaging this very expensive system.  Secondly, a 5×2 meter bright orange balloon could interfere with local air travel so we could only launch with clearance from the local airport and when there were no planes or helicopters in the vicinity.  Due to these restrictions, we were only able to launch four times during the 10 day period.  Still we retrieved some valuable data on the boundary layer through these measurements. 

The first episode of fieldwork was a fun and valuable learning experience.  It showed that a large amount of ingenuity and cooperation are sometimes necessary to accomplish seemingly simple tasks, such as setting up a weather mast, when conditions aren’t ideal.  Examining the data also showed that despite all your efforts, data collection isn’t perfect and you have to report the errors or incompleteness of your data when presenting your results to the public. 

Click on the photo thumbnail for a larger version.  

The weather balloon.  

The 10 meter weather mast.  

The sonic anemometer.