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Meet the SPRINT experts

BLOG: Earth Observation expertise from Dr Sarah Johnson at the University of Leicester

Dr Sarah Johnson, Earth Observation ‘Lecturer in Practice’ and Research Fellow

Sarah Johnson joined the University of Leicester in 2014 after many years working in the commercial geospatial services industry, and has 20-plus years’ experience working in the UK space sector. As a result, she has strong interests in building academic-industrial partnerships and applying research into industry and NGOs. She has a PhD in ‘High resolution polarimetric imaging of biophysical objects using synthetic aperture radar’ from the University of Sheffield.

Sarah is one of SPRINT’s academic experts and is the Principal Investigator on the SPRINT project with Previsico.

What is your particular experience and expertise in space data, and related applications and capabilities?

My background is in using Earth Observation satellite imagery to monitor the surface of the Earth. Satellite Earth Observation has a huge number of uses in monitoring the land, the oceans and the atmosphere. My own interests are focused on the land including looking at land cover change, monitoring deforestation, assessing soil moisture and supporting agricultural activities.

One of the interesting things about Earth Observation satellites is they use a variety of different wavelengths to see more than the human eye can see. Hence, while we use normal visible light (red, green, blue) we also use near infrared and red-edge bands which can tell us more about some targets. Similarly, we can use radar wavelengths to create what is essentially a microwave image of the Earth’s surface. This is an area I’m particularly interested in as radar has the ability to penetrate cloud cover and additionally see at night. This means it’s a hugely powerful tool when we want to monitor flooding – which invariably occurs when the weather is cloudy. Radar also has the advantage that it is very sensitive to water and hence it makes the ideal tool for monitoring flood events.

What is your interest in the related areas of flood warnings, disaster resilience, etc?

I first became interested in flooding when I lived near York; a city well known for its ability to flood regularly. During the damaging floods in November 2000 when large areas of the city centre flooded, I saw first-hand the impact on people’s lives and livelihoods and how disruptive and devastating flooding could be. These days I still live in an area which is regularly affected by flooding; the village I live in flooded twice last year, with homes ruined, roads blocked for significant periods of time and lives significantly disrupted. Weather extremes seem increasingly more likely as the climate changes and hence we can expect further damaging events to occur. It was therefore only natural to want to use my background in Earth Observation to study the issue further and see whether satellite derived information could provide useful information to help prepare for flood events, and to monitor them when they do occur.

How valuable have the SPRINT projects been in your research experience and what are the benefits of working with the university and/or via SPRINT for commercial businesses?

I’m just starting my second SPRINT project with local company Previsico. This has been an invaluable relationship. Firstly, it’s always great to work with a partner who are dynamic and have bags of enthusiasm for their subject. I’ve been so impressed with their staff and their breadth of knowledge. Secondly, Previsico’s expertise is complimentary to my own. I provide the flood maps derived from satellite imagery and access to some of the latest research techniques in this area. They bring expertise in the latest flood modelling approaches. By working together, we can produce something that is far more valuable than each of us working on our own. This in turn, leads to knowledge exchange, where each partner has been learning more about the other’s areas of expertise.

The key power of SPRINT projects is in ensuring that academic research is transferred into real world applications which can make a real difference companies, organisations and individuals. In this case, by blending the satellite derived flood maps with flood models, we can enhance the accuracy of flood models. This leads to more accurate forecasts of flood events and better assessment of areas that are damaged which is essential information for organisations managing their assets and insurers responding to flood events.

SPRINT has also been invaluable in being funding which was awarded quickly. This is hugely important in enabling SMEs to move forwards rapidly with their service development plans, rather than having to wait a long time for funding which may have a negative impact on their activities.

What are the potential areas for innovation in your particular sector for business growth, new applications, technology, etc?

The availability of satellite imagery has come on a lot in recent years with more regular and routine supply of imagery. This is particularly through the European Copernicus programme which provides freely available satellite imagery for anyone to use. However, there are also increasing numbers of commercial providers with the ability to both provide routine imagery or rapidly task imagery in the case of a major event. This is a real asset as it allows us to capture far more timely information about flood events.

The other issue to consider is that Earth Observation data is not used in isolation but with other information such as data from ground sensors or even social media. Combining satellite imagery with ground sensors is going to be a particularly important innovation going forwards. Ground sensors provide hyper temporal detailed information about single point locations, whereas satellite imagery provides a much wider spatial information but with less updates. Hence blending the two together will be an increasingly powerful tool to understand in more detail the timing and extent of flood events. This is something we’re looking at with Previsico and hoping to develop further together in future work.