Research
Glaciological remote sensing
My research operates at two scales, local scale investigations of processes towards new algorithms that are applied on the regional to continental scale to investigate climate and environmental change. The emphases of my research have been glaciological and radar remote sensing although elements of optical remote sensing, environmental monitoring and GIS are found.
Working on Blåmmansisen and Svartisen, Norway, I have built up a dataset of SAR and field data spanning more than a decacde. On Blåmannsisen I have investigated backscatter sensitivity to snowpack parameters using in situ data and backscatter models. This work has developed into three threads: multi-sensor observations of glacier downwasting, SAR and ground penetrating radar measurements of firn depth near the firn line (in collaboration with S. Ingvander), and multi-frequency polarimetric scattering decomposition towards a better understanding of scattering processes in snow and firn. On Svartisen, M. Jackson (NVE, Oslo) and I are working on correlations between SAR backscatter and winter and net surface balance using empirical corrections for surface scattering.
Scaling up I have been working a project to investigate the spatial variation in snow grain size in Dronning Maud Land (DML) with S. Ingvander and P. Jansson. SAR data backscatter modeling suggested that grain size or layering is an important control on backscatter varaiations in DML (Brown and Sandgren, 2008) and this project aims to test this hypothesis using grain size data collected along a traverse of DML.
At the continental scale M. Johansson and I are investigating the spatio-temporal dynamics of surface lakes and streams on the Greenland icesheet using multi-sensor data. The surface hydrology is linked to the basal hydrology and thus the dynamics of the ice sheet This research couples continental scale remote sensing challenges with glaciological investigations and is in collaboration with P.Jansson and J.Kleman (DPGQG).
With A. Mercer I have been working on spatial trends in glacier termini and area change. Using a combination of remote sensing and GIS methods we are analysing multi-temporal glacier data to investigate spatio-temporal patterns of glacier change, for the entire population of Swedish glaciers, between the mid 20th and early 21st centuries.
Applied Environmental Remote Sensing
In Africa I am supporting research by L-O. Westerberg and S. Mwanansu investigating the dynamics of mangrove forest in the Rifuji Delta. In this project I provide remote sensing support to socio-environmental research.
In Sudan I am using high resolution satellite data to investigate spatio-temporal vegetation changes at the village and landscape scale. This research aims to quantify vegetation and climate changes in the period prior to the onset of conflict in Darfur to assess the role of resource scarcity in the causes of the conflict.
Figure: A keyword cloud of article and proposal titles. The figure shows the relative frequency of occurance of the terms.