Marijke de Vet
Tell us about yourself:
My name is Marijke de Vet and currently I am a PhD researcher at the Energy and Environment Institute at the University of Hull, UK. I started my career within Earth Sciences with a bachelor and master’s degree in Civil Engineering at Delft University of Technology in the Netherlands. Before I started my PhD research I worked a couple of years as a coastal scientist at HR Wallingford, UK.
What is your research about?
My current research focuses on the influence of cohesive sediment on flow properties. High concentrations of suspended sediment in fluvial and submarine environments are common due to landslides, floods, hillslope failures, and post-wildfire erosion, phenomena that are likely to occur more frequently due to climate change. Small concentrations of cohesive sediment can already enhance or suppress turbulence due to the cohesive properties promoting flocculation. However, spatial and temporal scales of turbulent-laminar transitions in naturally unsteady flows are unknown, but key for understanding how fluvial environments react to changes in velocity in cohesive sediment-laden flows. During my research, I have conducted several physical experiments where I researched the effect of cohesive sediment on non-uniform flow conditions within open channel flows and gravity currents. The experiments highlighted complex interaction between turbulence and flow transitions. Understanding the influence of non-uniform flow conditions on sediment transport rates can have large influences on the spread of sediment around an environment.
What excites you about your research?
My specific interest in clay started during a master course given by Prof. Han Winterwerp and Dr. Bram van Prooijen covering all aspects of cohesive sediment. They showed me how fascinating cohesive sediment can be and how all aspects such as flocculation, flows, types of clay, waves and many more interact and how complex these systems can be. The combination of the complexity of the material, the amount of unknowns still within the field and the possibility of conducting physical experiments to learn and understand better how this material behaves excites me more and more over time.
What broader importance does your research have for society?
Cohesive sediments are ubiquitous in terrestrial and shallow to deep marine aquatic environments. Clays and fine silts are transported by a large variety of flows and commonly occurring higher concentration flows have significantly different fluid-dynamic characteristics to clear water or low-density flows. This influences the location the material is transported to, the volumes that are transported and the large concentration flows can influence the geohazard risk posed to infrastructure and landscape evolution. Understanding of sediment transport is vital for several aspects of society including protection against flooding and coastal erosion.
What inspired you to pursue a career in Earth Science?
As a child, I have always enjoyed any type of water sports (swimming, sailing, surfing) or going to the coast. When I was younger, I already found the coast most impressive in the winter (storm) season when there is a strong wind blowing and the sea is covered in powerful, strong, high waves. During my degree in Civil Engineering at Delft University of Technology, I found it fascinating to learn more about the physics of waves, flows and how we can protect a country against those extreme forces of nature. Learning to understand how the earth works I find intriguing but is also extremely important to understand how to live with nature to protect our earth.
What are you looking to do after you complete your PhD or postdoc?
If possible, I would love to continue conducting research into sediment transport either through physical experiments or running field campaigns. I absolutely love planning, setting up and conducting experiments. Working together to set up the experiments, being covered in clay and observing physics in reality, what not to love. Although depending on where life takes me, I might open my own bakery one day!
Given unlimited funding and access to resources, what is your dream project that you would pursue?
Field campaigns and physical experiments are very often influenced by the limited budget, whereas there are still so many unknowns within the field of sediment transport of (cohesive) sediment. With unlimited funding (plus unlimited time!), I would love to expand the physical experiments I have done to larger scales, more experimental runs to get more detailed insight, combinations of sediment types, and then field campaigns to compare the measurements.
What else do you do? Any hobbies or interests outside of work?
Outside of work, I spend my time cycling and hiking while exploring the UK countryside. My favourite bike ride is to a local café to trail their home-baked cakes for inspiration for my own baking. My ultimate favourite sport is long track speed skating!