Fjallsjokull system deployed

Today we set up two dGPS units to measure the speed of some of Fjallsjökull glacier. We chose an area of ice which is clearly moving forward towards the lake.

Here is the dGPS system setup on Fjallsjokull, with Jane Hart and Frey

The photo above shows a “quadpod” supporting the GPS units – which are an adaptation of those made by Matthew Roberts of the Icelandic met-office. The idea is to be strong enough to cope with winter and cast few shadows (which cause ice to grow). The system is currently measuring its position every 3hrs to an accuracy of about 2cm – using signals from the base station to help it.

the dGPS base station installed on a moraine close to the Fjallsjokull glacier. We used speaker stands burried in rocks to support the GPS antenna (top) and hold its 2.4GHz radio antenna (white stick). Shortly after this photo I accidentally kicked sand into the laptop keyboard – so it was not so easy to use after that!

View of Fjallsjokull with our deployement being almost in the middle of this photo.

Iceberg Tracker moves on but seems in trouble

Iceberg tracker temperatures from 9/8/16 to 7/10/16

Iceberg tracker temperatures from 9/8/16 to 7/10/16

We have been checking the iceberg tracker temperature as one way of telling if it is in the sea is a flatter daily variation in temperatures. Here you can see it did regularly read sub-zero at midnight then warmer an noon. Recently however it is showing mainly positive temperatures.

iceberg tracker locations up to 7/10/16

iceberg tracker locations up to 7/10/16

After spending weeks among the small islands in the centre of this map – it has moved south until reaching land again. This dramatic movement may be because the iceberg has broken up.

View of the icebergs when the tracker was deployed

this shows the glacier-sea front where icebergs calve (Photo: Formula E)

this shows the glacier-sea front where icebergs calve (Photo: Formula E)

The sea near the glacier - with a variety of icebergs (Photo Formula E)

The sea near the glacier – with a variety of icebergs (Photo: Formula E)

Formula E driving on a glacier in Greenland. This photo shows the icebergs in the sea - like the one we are tracking from here. Photo courtesy Formula E team.

Formula E car driving on a glacier in Greenland. This photo shows the icebergs in the sea – like the one we are tracking from here. Photo courtesy Formula E team.

Iceberg tracker

This is a GPS tracker we quickly built as a test of tracking icebergs – it uses Satellite (Iridium) short text messages to send its location to us every 12hrs. Inside is a large lithium battery pack. The photo below shows a water test in the sink – just in case it ends up in the sea. We used a unit from YB Tracking. More info later!

GPS satellite tracker we built for a test on a Greenland iceberg

GPS satellite tracker we built for a test on a Greenland iceberg

Getting going on CT analysis of till texture

We’re investigating the texture of till using CT scans. This shows successive sections through a sample.

Animated CT volume

Moving along the z-axis through a CT volume

The first step in the analysis is to extract the shapes of the clasts (rock fragments) embedded in the sample. These show up mainly as red in the sections above. The shape below is a clast about 3 mm long.clast