Cullen Scholar - Catherine Jordan

The Marine Institute is highlighting the postgraduate students completing projects as part of the Cullen Scholarship Programme. The programme builds national marine research capacity and capability and equips graduates with the skills and expertise in raising awareness about our ocean, as well as Ireland's rich marine biodiversity and ecosystems.

Catherine Jordan. Photo Andrew Downes, Xposure

Catherine Jordan

Title of Research: Space based observations of marine phytoplankton in North-East Atlantic waters

Higher Education Institution: National University of Ireland, Galway

Supervisors: Prof Peter Croot (NUI Galway) and Dr Caroline Cusack (Marine Institute)

What is your area of research?
My research focuses on using marine phytoplankton to detect and monitor high biomass phytoplankton blooms from space. I look at different algorithms and instruments that we can use to remotely monitor the colour of our ocean.
Marine phytoplankton are extremely important in the ocean as they form the foundation of the food web for most marine life. They play an important role in biogeochemical cycles and generate oxygen; all phytoplankton photosynthesize, meaning they consume carbon dioxide and release oxygen.
When conditions are right, some phytoplankton populations can grow explosively, and form a 'high biomass bloom' and sometimes these are visible from space.
Satellite ocean colour sensors measure the sunlight scattered back to the satellite from seawater. Sunlight interacts with the ocean in different ways, depending on what particles it interacts with, and phytoplankton tend to reflect back a green colour, but this can vary with species. Scientists can monitor the change in the ocean colour to estimate chlorophyll concentration and ultimately the biomass of phytoplankton.

Why is your research important to Ireland's marine sector?
In most cases, phytoplankton blooms are of great benefit to the overall ecosystem as they are a source of food for wild fisheries and aquaculture from the smallest organisms to the largest marine mammals in the ocean. However, some algal blooms can have a negative impact on their surrounding environments, these are known as Harmful Algae Blooms (HABs). HABs can result in serious economic loss to tourism, aquaculture and fisheries and in turn result in major health impacts. HABs can have a negative impact on an ecosystem by depleting the oxygen in the water and a small proportion of phytoplankton species produce toxins, although the HABs that produce toxins tend to bloom at low biomass, therefore they are generally not detected by satellite ocean colour sensors.
In order to mitigate the effects of blooms, early detection methods are always being explored. Satellites can detect high biomass blooms, if they present in surface waters, and provide early wide-scale warning to aquaculture and fishery industries.
Remote sensing techniques are powerful tools to monitor and identify a range of parameters in the ocean and on land over vast distances.
In April 2021, a research article was published on testing a new algorithm in Irish waters and showing the importance for detecting and monitoring high biomass HABs in Irish waters from space:

What has been the benefit of being part of the Marine Institute's Cullen Scholarship Programme?
I really enjoy being part of the Cullen Scholarship Programme, I have been given amazing opportunities to travel abroad to Germany and the United States to learn new skills for my research and also taken part in some incredible research cruises on the RV Celtic Explorer and RV Celtic Voyager. It is also great to be part of a bigger team of Cullen Scholars and hear about each individual's research and get to collaborate with them.

What have been some of the memorable experiences during your Cullen Scholarship?
The most memorable experience during my Cullen Scholarship and probably my career so far was when I got the opportunity to travel to America for a month in 2019 and do a placement at NOAA's National Centre for Coastal Ocean Science and learn about the satellite algorithms they use for HAB monitoring. I was able to bring this knowledge back to Ireland and collaborate with a team of international scientists on my first scientific publication.
Also, some other memorable experiences during my Cullen Scholarship would be spending weeks at sea on our national research vessels surrounded by nothing but water, in every type of weather from rough to flat calm seas, seeing dolphins and whales and the most amazing sunsets at sea. I have taken part in multidisciplinary surveys and had the opportunity to learn about many areas of marine science. I have had the opportunity to research technology that is very new to Ireland which is both challenging and rewarding and work with some incredible scientists from the Marine Institute, NUI Galway, Germany and the United States of America.


Editor's Notes:
The Cullen Scholarship Programme has provided grant aid to the value of €3.8 million supporting 36 PhD and five MSc students from 2014 to 2021. The research addresses a number of the 15 research themes identified in the National Marine Research & Innovation Strategy 2017-2021. This scheme is funded by the Marine Institute under the Marine Research Programme with the support of the Irish Government.