I am coming towards the end of my first year as a PhD student with the SENSE Earth Observation CDT, a Centre for Doctoral Training which aims to produce the next generation of satellite data specialists. My project is funded by NERC and the UK Space Agency and is partnered with the British Antarctic Survey.
My background is in Environmental Science, having studied for an integrated master’s at the University of Leeds. I also completed a year abroad at Monash University in Melbourne, Australia.
Master’s dissertation project: ‘Arctic Vegetation in a Warmer World: the Analogous Nature of the Pliocene’. This project involved modelling the distribution and abundance of Arctic vegetation during the mid-Pliocene warm period, an interval of time in Earth’s history around 3.3 million years ago whereby the climate was similar to that currently being experienced under greenhouse gas warming. The aim was to test if the distribution of Arctic vegetation during the mid-Pliocene climate could project the future of current Arctic vegetation by the year 2500, when rising atmospheric carbon dioxide concentrations have levelled out. This is important for understanding climate feedbacks which may help to amplify and/or dampen climate change. Overall, the mid-Pliocene was determined to be insufficient for indicating future Arctic vegetation distributions and abundances.
PhD project: ‘Multi-scale mapping of Antarctica’s terrestrial vegetation using optical satellite and UAV imagery’
Context:
Ice-free areas make up around 0.18% of the Antarctic continent and yet contain nearly all of Antarctica’s biodiversity and life, including seals, penguin colonies and terrestrial vegetation (lichens, mosses, algae and grasses). At the end of the twentieth century, the Antarctic Peninsula experienced one of the fastest rates of surface warming on Earth, a trend which is predicted to continue over the next century. The effect of an increase in ice-free land from ice and snow melt, coupled with a change in environmental conditions, has largely unknown consequences for the terrestrial ecosystem in Antarctica. Therefore, more mapping and monitoring surveys are needed to quantify change and assess impacts on the Antarctic biosphere. Remote sensing provides an efficient means of doing so.
Aim:
The aim of this PhD is to develop new remote sensing methodologies for discriminating and mapping terrestrial vegetation across Antarctica at different spatial scales, using a combination of machine learning, spectral unmixing and vegetation indexing techniques. Sentinel-2 satellite imagery will be used to map vegetation across all of the ice-free areas in Antarctica and UAV imagery will be used to map vegetation species and assess their spatial distribution patterns in relation to thermal microclimates on Robert Island.
However, to robustly map Antarctica’s vegetation the challenge of spectral reflectance variability in space and time must be addressed. This is where the way in which vegetation reflects incoming solar radiation changes depending on its hydration status, health and colour. Incorporating this effect into classification models is of utmost importance for reliable spatial and temporal mapping of Antarctic vegetation and represents an obstacle which I majorly aim to overcome.
Supervisory team:
Claudia Colesie (plant physiologist, UoE), Andrew Gray (remote sensing specialist, UoE), Peter Convey (terrestrial ecologist, British Antarctic Survey), Kevin Newsham (terrestrial ecologist, British Antarctic Survey).
Contact:
Email: Charlotte.Walshaw@ed.ac.uk
Cryptogamiacs research group: Cryptogamiacs – A seriously cool page about cryptogams (ed.ac.uk)
