Geospatial Systems - Rachel Walker
In partnership with
Profile
Rachel Walker
Biography
About Rachel Walker
My name is Rachel Walker, and I joined the third cohort of the EPSRC CDT in Geospatial Systems in September 2021.
My background is in Geography; I completed a Geography BSc at the University of Leeds in 2013 with specific areas of interest including geomorphology, climate and GIS. After my degree I completed my Geography PGCE at the University of Bristol and taught Geography, mainly to 13–18-year-olds until summer 2021. Throughout the PGCE and further CPD, I completed work at master’s level, read about key world issues and started to become interested in coding.
Although studying for a PhD was always a consideration, it was not until I found the Geospatial Systems CDT that I decided to apply for one. The support on offer and the potential to develop a range of skills throughout the four-year programme really appealed, as did the within and cross cohort collaboration. The CDT has enabled me to develop new skills in remote sensing, whilst also extending my Python and GIS skills.
Geospatial is a rapidly growing area and is increasingly important to tackle world issues. I am keen to be involved in researching climate change mitigation strategies, with a particular interest in using geospatial data to aid carbon sequestration to reduce the volume of carbon dioxide in the atmosphere. However, am also keen to work in other areas which relate to other world issues. Following my PhD, I am open to working in industry, government or academia.
Both my MRes and PhD focus on peatlands as although these landscapes only cover 3% of the land surface, they contain over 30% of the terrestrial carbon store. As a result, it is important that they are monitored and restored to enable carbon to be sequestered rather than released (degraded peats change from a carbon sink to a source and 80% of the UK’s peat is degraded so affects our ability to meet emission reduction targets). Additionally, peatlands provide a range of other ecosystem services including water management and habitats for a range of species.
My MRes title was A Hyperspectral Approach to Understand the Association Between PSM (as measured by InSAR Data) and Vegetation Assemblage for a Scottish Peatland. Using machine learning, the hyperspectral data was able to accurately map plant functional types across four sites (one near-natural, two undergoing forest-to-bog restoration and one eroded) in the Flow Country.
Research
PhD Research
My PhD studies continue to analyse hyperspectral and PSM data to assess peatland condition, but expand to include other datasets and more blanket bog locations in both the Flow Country and the North Pennines AONB. In the Flow Country hyperspectral data collected at a range of spatial scales are being analysed and compared (ground, UAV, piloted airborne and EnMAP satellite). Whereas, in the North Pennines, ground vegetation survey and hanheld spectrometer data are being used to analyse UAV multispectral data to determine whether multispectral data provides enough information where funds cannot cover hyperspectral data collection. Additionally, InSAR coherence data is being analysed across both peatlands to assess whether this freely available data can be used as a proxy for temporal changes in hydrology. Additionally, this data is being analysed in relation to changes in amplitude data to assess the impact of loading on peat surface motion measurements. These different data sets will then be combined to assess the relationship between hydrology, ecology and mechanics of the peatlands.
In addition to my PhD, I am also working as a Rights Lab Research Associate in Geospatial Data Science and Earth Observation (Rights Lab) in a variety of projects. Primarily, I work in a team focused on creating a model to determine the prevalence of bonded labour in multiple Indian states. Much of this work has been part time, but I also conducted a four-month placement in the Rights Lab from September to December 2024. Additionally, I have demonstrated in the Chemical Engineering Geology module for three years.
