Lisanne Braat

Lisanne Braat
European Space Agency | ESA

PhD

About

33
Publications
8,582
Reads
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529
Citations
Introduction
I obtained my PhD in May 2019 on the morphodynamics and sedimentology of estuaries. I focussed on the deposition of mud layers and their effects on the large-scale morphology and dynamics of estuaries. At the moment, I am interested in applying Earth science morphological research methods to the surface of Mars. At the moment my focus is on sediment transport and deltas.
Additional affiliations
March 2020 - April 2021
California Institute of Technology
Position
  • PostDoc - Rubicon Fellow
July 2019 - January 2020
Utrecht University
Position
  • Researcher
January 2015 - January 2019
Utrecht University
Position
  • Supervisor Field Work
Description
  • Supervising 1st year’s BSc students during fieldwork in France (Hautes-Alpes) for 4 years on geology, morphology and hydrology.
Education
September 2012 - November 2014
Utrecht University
Field of study
  • Earth Surface and Water
September 2009 - September 2012
Utrecht University
Field of study
  • Earth Sciences

Publications

Publications (33)
Article
Rivers and estuaries are flanked by floodplains built by mud and vegetation. Floodplains affect channel dynamics and the overall system's pattern through apparent cohesion in the channel banks and through filling of accommodation space and hydraulic resistance. For rivers, effects of mud, vegetation and the combination are thought to stabilise the...
Article
Mud plays a pivotal role in estuarine ecology and morphology. However, field data on the lateral and vertical depositional record of mud is rare. Furthermore, numerical morphodynamic models often ignore mud due to long computational times and simplifications of mixed depositional processes. This study aims to understand the spatial distribution, fo...
Preprint
Full-text available
Rivers and estuaries are flanked by floodplains built by mud and vegetation. Floodplains affect channel dynamics and the overall system's pattern through apparent cohesion in the channel banks and through filling of accommodation space and hydraulic resistance. For rivers, effects of mud, vegetation and the combination are thought to stabilise the...
Article
Full-text available
On the list of challenges facing the world largest deltas, increased saline water intrusion (SWI) in the surface water system and its role in jeopardizing freshwater supply are often ranked very high. Yet, detailed process-based studies of SWI at the whole delta scale are limited, and the trends are regularly associated with global sea level rise....
Preprint
Full-text available
In the list of challenges facing the world largest deltas, increased salt intrusion and its role in jeopardizing freshwater supply is often ranked very high. Yet, detailed process-based studies of salt intrusion at the whole delta scale are limited and the trends are regularly associated to global sea level rise. Here, using field measurements and...
Article
Full-text available
Mud accretion and establishment of biostabilizers, such as microphytobenthos and saltmarsh vegetation, govern the development of estuarine morphology. Mud facilitates saltmarsh survival and microphytobenthos growth, which in turn promotes sedimentation and reduces mud erosion. Consequently, an increasing extent and thickness of mud cover might lead...
Preprint
Mud plays a pivotal role in estuary ecology and morphology. Effectsof mud are often ignored in morphodynamic studies due to longer compu-tational times and limited field data. This study aims to understand thespatial distribution of mud layers in tidal bars, their formative conditions,preservation potential and their effects on the morphology of ti...
Article
Full-text available
The cover image is based on the Research Article Effects of estuarine mudflat formation on tidal prism and large-scale morphology in experiments by Lisanne Braat et al., https://doi.org/10.1002/esp.4504.
Article
Full-text available
The planform of estuaries is often described with an ideal shape, which exponentially converges in landward direction. We show how growing topographically forced nonmigratory (i.e., anchored) bars determine the large-scale estuary planform, which explains the deviations observed in the planform of natural estuaries filled with bars compared to the...
Article
Full-text available
Vegetation enhances bank stability and sedimentation to such an extent that it can modify river patterns, but how these processes manifest themselves in full-scale estuarine settings is poorly understood. On the one hand, tidal flats accrete faster in the presence of vegetation, reducing the flood storage and ebb dominance over time. On the other h...
Article
Full-text available
The interaction of marine (tides and waves) and fluvial processes determines the sedimentary fill of coastal systems in the fluvial-tomarine (FTM) transition zone. Despite frequent recognition of tidal and wave influence in modern and ancient systems, our understanding of the relative importance of marine processes and their impact on mud depositio...
Article
Full-text available
Human interference in estuaries has led to increasing problems of mud, such as hyper‐turbidity with adverse ecological effects and siltation of navigation channels and harbours. To deal with this mud sustainably, it is important to understand its long‐term effects on the morphology and dynamics of estuaries. The aim of this study is to understand h...
Preprint
Human interference in estuaries has led to increasing problems of mud, such as hyper‐turbidity with adverse ecological effects and siltation of navigation channels and harbours. To deal with this mud sustainably, it is important to understand its long‐term effects on the morphology and dynamics of estuaries. The aim of this study is to understand h...
Article
Full-text available
Cohesive floodplain sediment and vegetation are both thought to cause meandering river patterns. Our aims are to compare the isolated and combined effects of mud and vegetation on river planform and morphodynamics in the setting of intermediate‐sized valley rivers. We use a numerical model for century‐scale simulation of flow, sediment transport an...
Preprint
The planform of estuaries is often described with an ideal shape, which is exponentially converging in landward direction. We show how growing forced bars determine the large-scale estuary planform, which explains the deviations from the ideal planform for natural estuaries filled with bars. Experiments were conducted in a 20~m long, 3~m wide tilti...
Article
Full-text available
Vegetation enhances bank stability and sedimentation to such extent that it can modify river patterns, but whether similar strong biogeomorphological feedbacks exist in estuarine environments is poorly understood. On the one hand, tidal flats accrete faster in the presence of vegetation, reducing the flood storage and ebb-dominance over time, while...
Article
Full-text available
Analogue models or scale experiments of estuaries and short tidal basins are notoriously difficult to create in the laboratory because of the difficulty to obtain currents strong enough to transport sand. Our recently discovered method to drive tidal currents by periodically tilting the entire flume leads to intense sediment transport in both the e...
Article
Full-text available
Alluvial river estuaries consist largely of sand but are typically flanked by mudflats and salt marshes. The analogy with meandering rivers that are kept narrower than braided rivers by cohesive floodplain formation raises the question of how large-scale estuarine morphology and the late Holocene development of estuaries are affected by cohesive se...
Article
Full-text available
Estuaries typically show converging planforms from the sea into the land. Nevertheless, their planform is rarely perfectly exponential and often shows curvature and presence of embayments. Here we test the degree to which the shapes and dimensions of tidal sand bars depend on estuary planform. We assembled a dataset with 35 estuary planforms and pr...
Article
Full-text available
Alluvial river estuaries consist largely of sand but are typically flanked by mud flats and salt marshes. The analogy with meandering rivers, that are kept narrower than braided rivers by cohesive floodplain formation, raises the question how large-scale estuarine morphology and late Holocene development of estuaries are affected by cohesive sedime...
Article
Full-text available
Analogue models or scale experiments of estuaries and short tidal basins are notoriously difficult to create in the laboratory because of the difficulty to obtain currents strong enough to transport sand. Since Osborne Reynolds' experiments over a century ago, experimental tidal flow has been driven by periodic sealevel fluctuations. Recently we di...
Article
Full-text available
Scour holes often form in shallow flows over sand on the beach and in morphodynamic scale experiments of river reaches, deltas and estuarine landscapes. The scour holes are on average 2 cm deep and 5 cm long, regardless of the flow depth and appear to occur under similar conditions as current ripples: at low boundary Reynolds numbers, in fine sand...
Article
Alluvial fans develop their semi-conical shape by quasi-cyclic avulsions of their geomorphologically active sector from a fixed fan apex. On debris-flow fans, these quasi-cyclic avulsions are poorly understood, partly because physical scale experiments on the formation of fans have been limited largely to turbidite and fluvial fans and deltas. In t...
Article
Full-text available
Predicting debris-flow runout is of major importance for hazard mitigation. Apart from topography and volume, runout distance and area depends on debris-flow composition and rheology, but how is poorly understood. We experimentally investigated effects of composition on debris-flow runout, depositional mechanisms and deposit geometry. The small-sca...
Conference Paper
Full-text available
For the execution of field measurements around the Sand Engine during MegaPEX2014 there was a need for operational model predictions. Local river outflow causes non-uniform velocities and spatially complex current patterns near the Sand Engine. For assessing the optimal timing and location of the instruments and GPS drifters, information on the pre...

Projects

Projects (2)
Project
The aim of my PhD project is to study the effects of mud on the morphodynamics in estuaries. I address the 3D spatial pattern of cohesive mud layers and their effect on the natural dynamics on the scale of channel-shoal patterns and whole estuarine systems on time scales of decades and millennia.
Archived project
We studied the shapes and dimensions of tidal bars and channels, their dynamics over time and the initial formation of mutually evasive ebb- and flood tidal channels.