EO Detective ID LS2-2909-AH-cryo3
What do you work on?
I measure ice sheet grounding lines— the boundary between the floating ice shelf and the grounded ice sheet—from space. These are used to define the edge of an ice sheet and, in areas of rapid ice thinning, they are retreating inland at rates of over 1 km per year. This indicates the presence of ocean warming and is useful information for understanding contribution of ice sheets to sea level rise.
I have also had the chance to work in the Antarctic, living there for four months while I studied the Pine Island glacier. I was collecting field data with a radar that operates at the same frequency as the ESA CryoSat-2 satellite which I use for my research.
How did you come to be an EO Detective?
I received a BSc in Geography from the University of Edinburgh and an MSc in Space Studies from the International Space University in Strasbourg. I completed an internship with DLR, and was an ESA Young Graduate Trainee (YGT) in the Science Division of the Earth Observation (EO) department at ESA ESRIN and got my PhD this year from the University of Leeds.
What do these diagrams tell us?
The images show the velocities of ice streams on the West Antarctic ice sheet. The measurements were made by tracking features on satellite data acquired in 2015. You can see that the Pine Island glacier flowed over 130 m during the 12 days it took for the satellite to return to collect the next set of data. In this area of west Antarctica, ice speed has increased by over 40% in the last 25 years.
How is the data you use collected?
I use data from a wide range of satellites. Ice velocity and grounding lines are measured using Interferometry (InSAR) and feature tracking. Between 1990 & 2011, the SAR data came from ESA satellites such as ERS-1 and 2 and it is now being acquired by Sentinel-1. I also use radar altimetry satellites such as CryoSat-2 to measure changes in the ice sheet surface elevation. CryoSat-2 has measured ice thinning of up to 9 metres per year on Smith glacier: that’s a three-storey building every year!
What’s the best thing about your job?
I enjoy my work because I’m interested in the scientific problems I am trying to address, the wide variety of data and techniques available is challenging and interesting to work with, and the results I produce are very beautiful! More importantly than all that, I’m really lucky to work with a fantastic group of people who are all good friends—and that makes it even nicer!
Tell us about your favourite image of the Earth from space
My favourite picture at the moment is of a ship sailing through an algal bloom which is swirling with the ocean currents. The image was acquired by Sentinel-2, and is shown in ‘true-colour’ so that’s actually the real colour of the algae in the sea which I think is amazing!
What do you do in your spare time?
I like to go running, climb mountains (especially in Scotland), and go sailing in one-man boats. I’m very good at un-capsizing them as I’m not very good at sailing so I’ve had a lot of practice!