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Inga KoszalkaAssociate professor

About me


Inga Monika Koszalka
Associate Professor of Coastal Oceanography
- Baltic Sea Fellow

Research Gate, Google Scholar, ORCID

NEWS

ERASMUS student from Marseille Foucaut Tachon joined my group to work on his master thesis during spring 2022. He will contribute to the DriftBloomClim project.

Attended a meeting with a team of students from Junior Academy where we shared ideas about monitoring of plankton blooms and mitigating eutrophication - that was an inspiring experience, good luck with your project!

First results from the surface drifter project DriftBloomClim presented at the Bolin Days. Six specially designed surface drifters were deployed in the Western Gotland Basin in Fall 2021 to quantify turbulent transport and wind drift in the Baltic Sea and to evaluate ocean forecast models to represent these processes. The project is a collaboration between the Bolin Centre for Climate Research and the Stockholm University Baltic Sea Centre. More information here: sv, eng

Matteo Masini joined my group as a PhD student in September, 2021. He will investigate dynamics of the upwelling systems in the Baltic Sea and their impacts on biogeochemistry and primary production.

RESEARCH

I am Associate Professor of Coastal Oceanography at the Department of Meteorology, Stockholm University (MISU) and I am also a research fellow (Baltic Sea Fellow) at the Stockholm University Baltic Sea Centre.

I have a broad background and scientific interests spanning various topics of Geophysical Fluid Dynamics. The focus of my current research is on mesoscale- and regional ocean circulation, its variability as well as ocean interactions with atmosphere, cryosphere and biosphere. In my research, I employ observations, idealized ocean models and regional ocean model output, Lagrangian analysis and modelling, statistical methods, and theory. My studies often address ocean turbulence and turbulent dispersion which are not well understood yet important element of the climate system and require hollistic and novel approaches. My study domain considers primarily the Atlantic Ocean, the Nordic Seas, Greenland shelves and fjords as well as the Baltic Sea where I started my oceanographic studies as an undergraduate student. More information about my teaching can be found under the link RESEARCH at the bottom of the page.

TEACHING

Since I joined MISU in 2019, I have been course responsible for the MISU Master's Programme in Atmospheric Sciences, Oceanography and Climate Physics courses: Geophysical Fluid Dynamics and Physical Oceanography. I have developed the later course including an oceanographic cruise on R/V ELECTRA and a data analysis lab at the Askö station in collaboration with the Stockholm University Baltic Sea Centre. I am also contributing teacher to the PhD courses Advanced Oceanography and Advanced Mathematical Methods (now a responsible teacher for the latter). In 2019 I organized and co-taughed two Machine Learning workshops for PhD students (SeRC and CIM). I served as a Director of Undergraduate Studies at MISU in spring semester 2021.

During my earlier work appointments in US and Germany, I taught several courses at the undergraduate, master and doctorate levels, including Geophysical Fluid Dynamics, sea-going physical oceanography, Regional climate variability, Statistics for climate scientists, Thermohaline circulation, and Lagrangian analysis and dispersion (a self-developed master course). I have also organized and taught workshops in Statistics and Machine Learning. More information about my teaching can be found under the link TEACHING at the bottom of the page.

Education

2005-2008: PhD in Fluid Dynamics, Politecnico di Torino, Turin, Italy
1999-2004: M.Sc in Physical Oceanography, University of Gdansk, Poland
2001-2002: Student in Arctic Geophysics, UNIS (University Courses on Svalbard)

Employment

2019-present: Associate Professor, MISU, Stockholm University, Sweden
2015-2019: Junior Professor, GEOMAR and Kiel University, Germany
2011-2014: Assistant Research Scientist, Johns Hopkins University, Baltimore, USA
2008-2011: Postdoctoral Researcher, University of Oslo, Norway

Visiting appointments

2010, Oct-Nov: Norwegian Polar Institute, Tromsoe, Norway
2006, May-July: Woods Hole Oceanographic Institution, USA (Mary Sears Fellow)
2005, Jun-Aug: Woods Hole Oceanographic Institution, USA (GFD Fellow)
2004, Oct-Dec: International Centre for Theoretical Physics, Trieste, Italy

Fellowships and awards

2019: AGU 2018 Editor’s Citation for Excellence in Refereeing
2005: GFD Fellow, Woods Hole Oceanographic Institution, USA
2004: PhD Scholarship `Progetto Lagrange', Politecnico di Torino, Turin, Italy
2003: Scholarship Award, Ministry of National Education and Sport, Poland

Oceanographic cruise experience

Tvären Basin MO8013 (leader, teacher), R/V ELECTRA, 12/11/2021
Western Gotland Basin Cockteil (participant), R/V ELECTRA, 26/08/2021 (DriftBloomClim drifter deployments)
Western Gotland Basin (leader), R/V ELECTRA, 17/06/2021
Landsort Deep MO8013 (leader, teacher), R/V ELECTRA, 15/11/2019
Gotland Basin (researcher), R/V Elisabeth Mann Borgese, 8-24/07/2019
Baltic Sea Student cruise (teacher), R/V , 3 days, 09/2018
Baltic Sea Student cruise (teacher), R/V Alkor, 4 days, 08/2017
Baltic Sea Student cruise (teacher), R/V Alkor, 4 days, 08/2016
Baltic Sea Student cruise (teacher), R/V Poseidon, 4 days, 10/2015
Barents Sea (researcher), POLEWARD project, R/V G. O. Sars, 24/06–1.07/2009
Norwegian Sea (researcher), POLEWARD project, R/V Hakon Mosby, 6–11/10/2008
East Coast US (researcher), SW06, R/V Endeavor, 3–17 08/2006
Baltic Sea student cruises (student), R/V Oceanonograf II, 15–21/07/2003
Fram Strait Greenland Sea (UNIS student), R/V Lance, 22–26/08/2002
Kongsfjord, Svalbard (UNIS student), R/V Haakon Mosby, 6–8/09/2001

Group

Current members

Foucaut Tachon, Master student (ERASMUS/Aix-Marseille University), Main advisor.
01/2022-present (Disentangling plankton dynamics in a turbulent sea from Lagrangian trajectories).

Matteo Masini, PhD student (MISU), Main advisor.
09/2021-present (Dynamics of upwellling systems).

Jonathan Wiskandt, PhD student (MISU), Main advisor.
05/2020-present (Proj: Ice-FEM-Ocean).

Stefano Ottolenghi, PhD student (Dpt. Mathematics, SU), Co-advisor.
10/2019-present (Proj: Ice-FEM-Ocean).

Past members

Johannes S. Dugstad, PhD student (University of Bergen), Co-advisor. Graduated: 11/2020.
Thesis title: "Water mass exchange, pathways and the mesoscale eddy field in the Lofoten Basin of the Norwegian Sea". (Proj: ProVoLo).

Ziqi Yin, Master student (MISU), Main advisor. Defense: 06/2020.
Thesis title: "Ice-ocean interactions in a Greenland fjord".

Mia Sophie Specht, Master student (GEOMAR/CAU Kiel), Main advisor. Graduated: 10/2018.
Thesis title: "Variability of Atlantic Water inflow onto the Northeast Greenland continental shelf". Mia had worked for me since 01/2017 as research assistant before commencing the thesis work in spring 2018 (Proj: FeedMeltPath/GROCE).

Joost Hemmen, Master student (GEOMAR/CAU Kiel), Main advisor. Graduated: 10/2018.
Thesis title: "Transport by mesoscale and submesoscale flows of the central Baltic Sea in a high resolution regional ocean model". Joost had worked for me since 08/2017 as research assistant before commencing the thesis work in spring 2018.

Jan Spliethoff, Bachelor student (GEOMAR/CAU Kiel), Main advisor. Graduated: 10/2018.
Thesis title: "Rafting through the 2015/2016 El-Nino: Oceanographic analysis of the Kon-Tiki2 expedition".

Patrick Wagner, Master student (GEOMAR/CAU Kiel), Co-advisor. Graduated: 03/2017.
Thesis title: "Eulerian and Lagrangian tracer spreading in an high resolution Ocean General Circulation Model".

Regina-Maria Keller, Bachelor Student (GEOMAR/CAU Kiel), Co-advisor. Graduated: 07/2016.
Thesis title: "Cross-frontal mixing in the Agulhas Current induced by its meandering".

Niko Schmidt, Student research assistant, Dpt. Math, CAU Kiel (08-12/2018).
(Proj: FeedMeltPath/GROCE).

Teaching

Teaching certificates:

Basics of University Teaching (Stefan Braun, Hochschuldidaktik.de): 2017.

Professional development course (Universitetslärarutbildning UL1), 7.5 ECTS, Stockholm University, 2020.

Professional development course NatFak (Universitetslärarutbildning UL2), 7.5 ECTS, Stockholm University, 2020.

Course development:

Self-designed Master Course Lagrangian Analysis and Dispersion (5 ECTS; 2016 & 2018)

Self-designed PhD course Statistics for Climate Applications (2 days; 2018)

Organized and co-taught three PhD-level courses on Neural Networks for Beginners (2019; 2 days each; 1 in Germany, 2 SeRC/CIM in Sweden accredited 3 ECTS each)

Developed Master Course Physical Oceanography (MO8013 MISU) by adding an observational module (a student cruise and data analysis lab) in  collaboration with the Baltic Sea Centre (2019-).

Teaching experience at MISU (2019-):

Course responsible for Master Course Physical Oceanography (MO8013), Lecture + Tutorial including oceanographic cruise with students (R/V ELECTRA, in collaboration with the Baltic Sea Centre). 7.5 ECTS: 2019, 2020, 2021-

Course responsible for Master Course Geophysical Fluid Dynamics (MO8009), Lecture. 7.5 ECTS: 2019, 2020, 2021-

Co-teacher for PhD Course Advanced Mathematical Methods, Lecture. 7.5 ECTS: 2021- (bi-annual; course responsible from 2023 onwards).

Co-teacher of a PhD course Neural Networks for Beginners featuring an invited
lecturer Prof. Ribana Roscher, University of Bonn and Osnabrück, Germany. The course
consisted of 3 days of lectures and tutorials with Python/TensorFlow. The course was given twice, as a SeRC (Swedish e-Science Centre) course on Frescati Campus, and as a CIM (Centre for Interdisciplinary Mathematics) course at Uppsala University. The courses were accredited 3 ECTS each and given in 2019.

Teaching experience at GEOMAR/CAU-Kiel (2015-2018)

During years 2015-2019 I held a position of Junior Professor at the GEOMAR Helmholtz Centre for Ocean Research Kiel and Kiel University (CAU), Germany, where I contributed to the Bachelor Program in Physics of the Earth System (Physik des Erdsystems), the Master Program in Climate Science (bi-annual turnover) and PhD–level courses.

Bachelor level:

Measurement Methods in Oceanography (tutor on oceanographic students, 2015, 2016, 2017, 2018);

Introduction to Oceanography (Lecture, co-teacher, 2016, 2017)

Master level:

Data Analysis and Statistics Lecture, 5 ECTS (2017, 2018)

Lagrangian analysis and Dispersion (Lecture+Tutorial, self-designed), 5 ECTS (2016, 2018)

Thermohaline Circulation Tutorial, 2.5 ECTS (2015, 2017);

PhD level:

Statistics for Climate Applications 2 days (2018)

Research Integrity, 1 ECTS (2017)

Neural Networks for Beginners (organizer), 2 days (2019).

Other teaching experience:

Spring 2013: Geophysical Turbulence and Transport Graduate Course (AS.270.620), Johns Hopkins University, co-lecturer with Prof. Anand Gnanadesikan.

2001/2002: Teaching Assistant in Remote Sensing and Polar Meteorology for Prof. Yngvar Gjessing at University Courses of Svalbard (UNIS).

 

Research

Lagrangian analysis and turbulent dispersion

Figure 1. Lagrangian analysis of the POLEWARD drifter trajectories in the Nordic Seas (from top-left): drifter trajectories, relative diffusivity, the principle for clustering of drifter segments and single particle diffusivity. From Koszalka et al (2009a) and Koszalka et al (2011).

The turbulent flows (eddies, jets, fronts) determine distribution of constituents suspended in the ocean (tracers): temperature, salinity, nutrients, marine algae and polluting agents. The turbulence also mediate the energy transfer between the large scale currents and the small scales where it is dissipated. The observation, quantification, as well as proper representation (parameterization) of turbulent transport in ocean climate models remains a major challenge for oceanography. The turbulent transport can be quantified by the spreading (dispersion) and the rate of spreading (diffusivity) of a cloud of drifting instruments (drifters, floats) deployed in a real ocean flow. Equivalently, it can be quantified by the rate of spreading of a cloud of numerical particles dispensed in a modelled ocean flow. Lagrangian analysis is a research field that studies ocean flow though analysis of motion of particles or instruments carried by ocean flow. Lagrangian modelling considers simulations of particles using velocity data outputted from ocean models or estimated from satellite pictures.

Lagrangian analysis modelling has been in my focus since my doctoral study of mesoscale ocean vortices (eddies) and the associated turbulent transport (Koszalka et al 2009a). Subsequently, I worked as a postdoctoral researcher at the University of Oslo under a POLEWARD project that featured a then-date-largest drifter pair experiment that took place in the Nordic Seas. It allowed to exhaustively assess surface turbulent transport with help of relative particle statistics (Koszalka et al 2009b). I also worked on development of methods for Lagrangian analysis including machine learning techniques (Koszalka & LaCasce 2010) that allowed to map the surface flow field in the Nordic Seas at an unprecended resolution (Koszalka et al 2011); to develop and apply stochastic particle (Markov) models to study propagation of warm water anomalies in the Nordic Seas poleward toward the Arctic (Koszalka et al 2013a) and to compare the surface turbulent transport diagnostics (eddy fluxes) from drifter data, satellite imagines and model output (Isachsen et al 2012). For full publication list from this project, see here.

Figure 2. Lagrangian trajectories in the Nordic Seas simulated using a stochastic particle model with different parameters and compared to the observed drifter trajectories. The tuned model was employed was used to estimate travel time for warm water anomalies toward the Arctic (Koszalka et al 2013a).

Recently, I have been working with my students and colleagues addressing application of turbulent dispersion and diffusivity to evaluate transport representation in regional ocean models (Rühs et al 2018), comparison of the tracer-derived and Lagrangian diagnostics for turbulent transport (Wagner et al 2019) as well as quantification of cooling of the warm Atlantic Water in the Lofoten Basin using 2D and 3D Lagrangian simulations and with respect to the seasonal variations (Dugstad et al 2019).

Figure 3. Turbulent diffusivity (a measure for turbulent transport) estimated from Lagrangian trajectories deployed in an ocean model runs of different resolution and compared to the observations (Rühs et al 2018).

Figure 4. Comparison of spreading of a numerical tracer and Lagrangian particles in a regional three-dimensional ocean model. For the diffusivity and other diagnostics see Wagner et al (2019).

Figure 5. Left: Density maps for 3D Lagrangian particles experiencing cooling and warming in the Lofoten Basin in different seasons. Right: Comparison of density maps for 2D vs 3D Lagrangian particles deployed close to the surface. See Dugstad et al (2019)..

I have also contributed to a community review article about Lagrangian analysis (Van Sebille et al 2018) and another one about drifting instruments (Centurioni et al 2019) where you can find more background information about Lagrangian analysis, modelling and observations.

Back to home page: Inga Homepage.

Dynamics of mesoscale eddies
and their role in oceanic transport processes

Figure 6. Diagnostics from a idealized study of eddies developing in a wind-forced ocean with a strong stratification. Top: Maps of surface relative vorticity [f] and verticakl velocity [m/s]. Bottom: Frequency spectra and vertical section of the vertical velocity ( Koszalka et al 2009a; Koszalka et al 2010).

During my PhD work I studies dynamics of ocean eddies using quasigeostrophic (QG) models as well as an idealized-realistic configuration of a strongly stratified ocean forced by wind of a regional circulation model (ROMS). Major findings were a strong dominance of anticyclonic vortices linked to the straining field exerted by vortex Rossby waves and strong vertical velocities due to interplay of eddies, vortex Rossby waves, and internal waves (Koszalka et al 2009a). In Koszalka et al (2010) I demonstrated that the vortices can act like islands of increased penetration of wind energy into the ocean interior and enhanced vertical mixing, and assessed how these eddy.mediated processes relate to the ambient stratification and how they can be affected by the climate change.

In my PhD I also studies interactions between the turbulent flow and plankton dynamics represented by theoretical mathematical models. For example, in Koszalka et al (2007), I showed that spatio-temporal variability coupled with advection by mesoscale eddies can disguise limit-cycle behavior in observed plankton abundance, thus prompting for a greater care in interpreting results from homogeneous plankton models.

The questions of the turbulent eddy dynamics and the associated transport have been returning in different context thoughout my career.

Back to home page: Inga Homepage.

Circulation of Greenland's shelves and fjords
Greenland Ice Sheet-Ocean interactions

Figure 7. Pathways of the dense Denmark Strait Overflow on the East Greenland Shelf mapped with help of Lagrangian simulations, and travel time distributions between the Denmark Strait Sill and the Angmassalik section further south in the Irminger Basin. The waters taking the shelf pathway and spilling to the deep basin exhibit longest travel times and undergo strong temperature and salinity changes (Koszalka et al 2013b).

The Greenland's shelf circulation was the focus of researcher appointment at the Johns Hopkins University, Baltimore, US. In Koszalka et al 2013b, I used Lagrangian simulations and a high resolution regional (MITgcm) model output to map pathways of the dense Denmark Strait Overflow (DSO) on the East Greenland Shelf hinted previously by sparse observations. I also investigated travel times and property transformation of dense water masses represented by model particles. In Von Appen et al 2014 we used backward Lagrangian simulations to investigate origins of a recently discovered current in the Irminger Basin, the intermediate-water Spill Jet, a potential contributor to the variability of the Deep Western 2Boundary Current (and the Atlantic Meridional Overturning Circulation). In Von Gerderloos et al 2017 we used backward Lagrangian simulations to map Atlantic warm water pathways toward the Kangerdlugssuaq fjord-glacier system. I have further studied inflow of the warm Atlantic Water towards the Greenland's marine-terminating glaciers under the FeedMeltPath–GROCE project at GEOMAR Centre for Ocean Research Kiel, Germany, and with a master student, Mia Sophie Specht.

I am continuing studies of ice sheet-ocean interactions under Ice-FEM-Ocean, a collaborative pair-PhD project with Josefin Ahlkrona (Dpt. Math, SU) our PhD students Stefano Ottolengo and Jonathan Wiskandt and colleagues Christian Helanow (Math) and Johan Nilsson (MISU). In spring 2020, master student Ziqi Yin completed a master thesis about idealized simulations of a glacial fjord using the VEROS model.

Back to home page: Inga Homepage.

The Baltic sea
Turbulent flows and bio-physical interactions

The surface drifter project DriftBloomClim (Bolin Centre RA3/SU Baltic Sea Centre)
Six specially designed surface drifters were deployed in the Western Gotland Basin in August/October 2021 to quantify turbulent transport and wind drift in the Baltic Sea and to evaluate the available ocean forecast models to represent these processes. The first results suggest that the velocity output from ocean forecast models is able to represent the drift within a few km over a 2-3 day, and futher improvement can be achieved through adjusting time step and the Lagrangian model. The project is a collaboration between the Bolin Centre for Climate Research and the Stockholm University Baltic Sea Centre. This is a first phase of an larger effort by the team Inga Koszalka (MISU)  and Agnes Karlson (DEEP) to develop forecast models for algae blooms in the Baltic Sea, that we aim at conducting in the future. Read more about the project here: sv, eng

Matteo Masini joined my group as a PhD student in September, 2021. He will work with me, Johan Nilsson (MISU) and Bo Gustafsson (The Stockholm University Baltic Sea Centre) and investigate dynamics of the upwelling systems in the Baltic Sea and their impacts on biogeochemistry and primary production.

Back to home page: Inga Homepage.