Fieldwork
Upcoming Fieldwork
Harbor-Induced Circulation And Sediment Transport (HI-CAST) 2022
Dr. Ludka, collaborators Drs. Connolly and Orescanin, and students will conduct a summer field experiment in Elkhorn Slough, an estuary in Moss Landing, CA. They will measure water velocity, water level, waves, temperature, salinity, dissolved oxygen, turbidity, sediment samples and bathymetry (seafloor elevation) using moorings, coastal radar, and small boat surveys. Learn more on our Projects Page.
Photo from USACE Digital Visual Library.
Dr. Ludka's PhD and Postdoctoral Fieldwork Experience
Dr. Ludka surveying Cardiff Beach, CA. Photo by Dennis Darnell.
Dr. Ludka helped collect observations of beach erosion and accretion in Southern California and used this data in her thesis work. This long-term dataset began in 2001 and continues today. For more information on the survey techniques see the SIO CPG website here.
Beaches and cliffs can erode rapidly during storms, followed by recovery that can take days to seasons. During this field experiment, beach profiles and cobble exposure were observed as often as daily at Torrey Pines State Beach, CA, combined with continuous observations of nearshore waves and runup. The overarching objective was to observe the effects of individual storms that cumulatively define seasonal and longer-time scale changes. Experiment Link Here.
The postdoctoral researchers (at the time) that helped design this experiment. Left-Right: Dr. Hiro Matsumoto, Dr. Julia Fiedler, Dr. Bonnie Ludka. Photo by Michele Okihiro.
Dr. Ludka recovered temperature sensors and current meters that had been deployed on Palmyra Atoll to calibrate coral climate records. Dr. Ludka also helped set up underwater photogrammetry targets for coral mapping.
Dr. Ludka, colleagues, and high school students spent two days on the Research Vessel Sproul through the UC Ship Funds Program. They collected a 16-day water temperature and velocity time series using a moored vertical thermistor array and bottom mounted ADCP (current meter) as well as two repeat cross-shore vertical CTD sections (measurements of salinity, temperature and depth) off Point Loma, CA. The goals of this experiment were
to provide a unique training opportunity for graduate students to design, coordinate and conduct ship-based field experiments as well as teaching and mentoring students.
to provide instruction at sea for high school students in the UCSD Academic Connections program.
to contribute to improving our understanding of local coastal upwelling processes in the San Diego region.
UC Ship Funds Link Here. Dr. Ludka was co-chief scientist with fellow graduate students (at the time) Dr. Veronica Tamsitt, Dr. Julia Fiedler and Dr. Sean Crosby. Photos by Dr. Julia Fiedler.
This experiment studied the exchange between the surfzone (where waves break) and the inner-shelf (shallow shelf just offshore of the surfzone) at Imperial Beach, California. Bright pink dye was used as a tracer to quantify the exchange and to measure the amount of along-shore and cross-shore dispersion. This research is applicable to understanding transport of tracers (e.g. pollution, larvae) in the nearshore region where humans and ecosystems are directly impacted. Dr. Ludka helped with rapid deployment of sensors as the dye plume evolved. Experiment Link Here.
A mega-nourishment called the "Sand Motor" was constructed off the Dutch coast of Ter Heijde and Kijkduin in 2011. It is a large artificial sandbank in the shape of a peninsula. Ocean currents, wind and waves are spreading the sand along the Delfland coast between Hoek van Holland and Scheveningen. Dr. Ludka joined over 40 researchers from the Netherlands, UK, USA, Sweden and South Africa for a six week field experiment in the fall of 2014 at the Sand Motor. Video Link Here.
Dr. Ludka learning how to use the river surveyor. Photo by Dr. Steve Elgar.
Dr. Ludka attended Woods Hole Oceanographic Institution's 2-week short course for graduate students interested in coastal, estuarine, and nearshore dynamics and transport processes. The class included one week of intensive lectures in Woods Hole, followed by a 3-day field component that provided hands-on experience in measurement techniques in estuarine, nearshore, and inner-shelf settings. Video Link Here (will be on right side of page)
The lectures addressed fundamental research issues in coastal, estuarine, and nearshore oceanography, focusing on the ways that modern field techniques are being used to address these questions. Lectures also addressed the planning, execution, and analysis of field programs, the capabilities and limitations of different field techniques, and the underlying principles of operation of key measurement systems such as CTDs, ADCPs, and other modern sensor systems. Scientific topics included tides, coastal currents, estuarine circulation, turbulent boundary layers, stratified mixing, surfzone processes, sediment transport, and morphodynamics.
The field segments for the 2014 class included the Connecticut River estuary, the surf zone and nearshore environment on the south side of Martha’s Vineyard, and the inner shelf to the south of Martha’s Vineyard. Measurement approaches included shipboard survey methods, moorings, tripods, autonomous vehicles, drifters, and other Lagrangian approaches. Instrumentation systems included CTDs, ADCPs, ADVs, kinematic GPS, optical and acoustic sediment measurement systems and interdisciplinary sensor suites. The students were involved with all aspects of planning, deployment, processing, and analysis of the data.
Lecturers and field instructors included Geyer, Lentz, Elgar, Trowbridge, Raubenheimer, Ralston, Traykovski, Kirincich, Lavery, Scully, and other expert practitioners of coastal field methods.
The Energetic Waves at Agate Beach (EWAB) experiment obtained observations of high energy, long period ocean swell waves propagating across a sandy beach and running up the beach face. Dr. Ludka and colleagues helped collect observations on the Oregon Coast that were used as part of Dr. Julia Fiedler's thesis. Dr. Fiedler tested and calibrated numerical models to simulate wave runup during storms. Experiment Blog Here. Photos by SIO CPG.
Dr. Ludka participated in a multi-institutional field study of the complex dynamics at New River Inlet in North Carolina.
The goals of this project are to improve understanding of, and to develop and test models for, the processes near a river mouth or inlet, including:
evolution of morphology, bathymetry, and bed roughness,
wave-current interactions in constricted flows,
wave evolution and breaking near strong currents,
circulation patterns, and
tracer dispersion.
Dr. Ludka completed the Scripps/UC San Diego Scientific Diving Course, which is a 100-hour course including: Physics and Physiology of Diving, Decompression Theory and Dive Planning, Equipment and Environmental Considerations, Scripps Scientific Diving Program and Policy, and subtidal sampling techniques; Dive Rescue; Diving Emergency First Aid (CPR, first aid, oxygen administration, field neurological examination, and hazardous marine life); Nitrox; Written Scripps Scientific Diver examination; and 12+ supervised open water dives. Program Information Here.
Dr. Ludka servicing an instrument on the Del Mar Mooring. Photo by Rich Walsh.
Header Photo: Sunset Cliffs Natural Park, San Diego California