ESR 1

Project Title: Understanding atmospheric Hg redox transformations from novel field observations and 3D atmospheric Hg models.
Host: UGA, Grenoble, France


Selected ESR: Alkuin Maximilian Koenig

Supervisor: A. Dommergue
Co-supervisor: J. Sonke (CNRS)
Enrolment in Doctoral degree: Université Grenoble Alpes, France


Context:
Atmospheric oxidation of the dominant emitted Hg(0) form is a key process whereby Hg from natural and anthropogenic sources is converted to more soluble and reactive Hg(II) species that will be deposited to ecosystems. Recent theoretical, field and experimental studies have proposed new atmospheric Hg redox pathways, including alternative oxidants, and direct photoreduction of Hg(II) forms. These new pathways need to be integrated in atmospheric Hg models and tested against observations of atmospheric Hg and oxidant dynamics.

Objectives:
To improve understanding of atmospheric Hg observations including the role of key oxidants, photoreduction and re-emissions.

Methodology & Expected Results:
This project relies on previously made Hg observations, and on state of the art atmospheric Hg models. The spatial and temporal variability of Hg(0) and Hg(II) species concentrations along with some oxidants (BrO, NOx, O3) will be investigated in regions where high oxidation rates are observed or suspected (polar regions, high altitude sites, tropical regions). An improved understanding of Hg(0) re-emission sources (snow, sea-ice, ocean, land) and their role in the atmospheric Hg budget will be proposed using available 1D and 3D atmospheric models. Improvement of reactions schemes and parametrization of Hg(0) oxidation and Hg(II) reduction using the latest version of the models (i.e. GEOSChem 3D) will be tested in high oxidation environments, using recent UGA/CNRS data and GMOS, AMNET data. ESR1 will work in close collaboration with ESR2, 10 and 14.

Planned secondment(s):
PSA/VSL (W. Corns/I.Krom) 1 month, traceable calibration for GEM and GOM, seconded together with ESR2 to collaborate with ESR10; CNRS (J. Sonke), 1 month, analytical techniques; MIT (N. Selin), 3 months, integrate novel field observations into global GEOS-CHEM 3D model; HZG (J. Bieser), 1 month, integrate novel field observations into 3D regional models, collaborate with ESR14.


ESR 2

Project Title: New experimental constraints on atmospheric Hg red-ox reactions.
Host: JSI, Ljubljana, Slovenia


Selected ESR: Sreekanth Vijayakumaran Nair

Supervisor: M. Horvat
Co-supervisor: A. Dommergue (UGA), J. Sonke (CNRS)
Enrolment in Doctoral degree: International Postgraduate School Jožef Stefan


Objectives:
The main objective is to understand aqueous Hg red-ox mechanisms and rates from an experimental perspective. This includes the Hg red-ox behaviour of Hg species in marine waters, atmospheric waters and in aerosols, in order to better understand deposition of oxidised fractions of Hg and re-emission of volatile inorganic Hg species, and the two-way flux of Hg species between oceans/atmosphere and land/atmosphere.  Close collaboration with ESR1, and ESRs 4, 5, 9, 10, 12, 14, 15

Expected Results:
(i) Experimental kinetic  rate constants for reduction reactions in the aqueous phase for Hg(II) complexes in seawater, rainwater, cloud water, aerosols , and of GOM in the gas phase under different wavelength regions (using solar simulator) (ii) validation of laboratory experiments with complementary field based experiments, and (iii) mechanistic understanding of photochemical reactions from the Hg stable isotope composition of products and reactants and (iv) improved representation of aqueous and gaseous redox processes in 3D regional and global Hg models (3 papers).

Planned secondments:
CNRS (J. Sonke) UGA (A. Dommergue) 2 months, photochemistry mechanisms studied by Hg stable isotope composition of products and reactants, Harvard (E. Sunderland), 1 month, training on modelling of biogeochemical cycling of Hg in different environmental compartments; HZG (C. Schrum, J. Bieser), 1 month, incorporation of new kinetic data into regional and global models, joint collaboration with ESR14; joint publication.


ESR 3

Project Title: Combining carbon, hydrogen and Hg compound specific isotope analysis to understand MMHg origin.
Host: CNRS, Toulouse, France


Selected ESR: Lisa María Malberti Quintero

Supervisor: D. Point
Co-supervisor: J. Sonke (CNRS); A. Lorrain (IRD)
Enrolment in Doctoral degree: Paul Sabatier University, France


Context:
All humans are exposed to toxic monomethyl-Hg (MMHg) when we consume marine fish. The origin of MMHg in marine ecosystems is however not well understood. MMHg formation is likely microbial, but could be abiotic. Which microbes methylate marine inorganic Hg is not known, and the role of the gaseous dimethyl-Hg form as a precursor or product of MMHg is also not known. The isotopic composition of Hg, carbon and hydrogen carry information on the sources and transformation pathways of MMHg, and are the topic of investigation in this PhD project.

Objectives:
to develop novel carbon (δ13C) and hydrogen (δD) isotopic tracers of the ’methyl’ group of the MMHg (CH3Hg) compound; to couple novel C/H isotopic tracers with Hg stable isotopic analysis; to explore and fingerprint the fundamental mechanisms at the origin of MMHg formation under laboratory-controlled experiments, in the field, during oceanographic cruises and in biological samples originating from different ocean basins.

Methodology and Expected Results:
This PhD project involves analytical chemistry, method development, analysis of environmental, biological samples, and minor fieldwork. The ESR will (i) validate methodologies for the 3D (δ13C-δD-δ202Hg/Δ199Hg) isotopic analysis of MMHg in natural samples at low concentrations (zooplankton); (ii) study 3D (δ13C-δD-δ202Hg/Δ199Hg) isotopic variations of MMHg during abiotic and biotic Hg methylation experiments, under controlled laboratory conditions;  (iii) document the 3D isotopic variations of MMHg in marine organisms collected from different study sites of ESR 4, 5, 6, 7. The trophic ecology and habitat of these organisms will also be documented by complementary analysis of δ13C, and δ15N signatures on individual amino acids.

Planned secondments:
IRD (A. Lorrain), 2 months, investigation of the 3D (δ13C-δD-δ202Hg/Δ199Hg) signatures of MMHg in marine food web in relation with marine predators foraging ecology; SU (S. Jonsson), 1 month, the role and interaction of CH3Hg with DOM; UPPA (D. Amouroux), 3 months, Hg/C isotopic fractionation during lab biomethylation reactions.

ESR 4

Project Title: Marine Hg species dynamics and distribution.
Host: AMU, Marseille, France


Selected ESR: Natalia Torres Rodriguez

Supervisor: L. E. Heimbürger-Boavida
Co-supervisor: D.Amouroux (UPPA); M. Horvat (JSI)
Enrolment in Doctoral degree: Université d’Aix-Marseille, France


Context:
Mercury is one of the least concentrated elements in the ocean, and its complex biogeochemical cyling drives ultimately the biomagnification of methylmercury into marine fish. Several key knowledge gaps must be filled to understand the marine biogeochemical Hg cycle. 1. One of the largest Hg flux occurs at the ocean-atmophere interface. Dispite the fact that This Hg exchange flux remains ill-quantified despite the fact that it is thought to be bigger than the annual anthropogenic Hg emissions. 2. The ocean remains undersampled and not all ocean basins have been mapped for Hg species. 3. Volcanic emissions are the only primary natural Hg source. Yet the magnitude of hydrothermal Hg emissions to the ocean remains virtually unknown. The UNEP Global Mercury Assessement 2018 has called to address those three knowledge gaps for a better understand of the global and oceanic mercury cycling.

Objectives:
ESR 4 will target key knowledgegaps of the marine biogeogemical cycle of mercury: 1. Refining the Hg flux at the ocean-atmopshere interface. The ESR will develop a first high resolution time-series of combined marine (DGM, other Hg species and methylation/demethylation incubations) and atmospheric Hg observations at a coastal Mediterranean site, 2. MapMap Hg species in the global ocean. The ESR will produce Hg speciation and incubation data in the only uncharted ocean basin, thethe Indian Ocean, 3. The ESR will sample hydrothermal vents during the Indian Ocean cruise and compare with samples from other hydrothermal vent sites. Collaboration with ESRs 1, 3, 5, 6, 11,13,14, 15.

Expected Results:
Provide a DGM time-series to better constrain the large exchange flux at the ocean-atmosphere interface (paper 1). Provide high-resolution full depth open ocean description of all Hg species (tHg, MMHg, DMHg, Hg(0), DGM), and Hg methylation/demethylation rates for thethe Indian Ocean, including some hydrothermal vents (1 paper). New observations will feed the GEOTRACES global database and be used to confront and update state-of-the-art numerical global open ocean models.

Planned secondments:
Tekran (E. Prestbo), 1 month, M4, implementation of DGM/TGM time-series measurements; UPPA (D. Amouroux), 1 month, M10, acquisition of isotopically-label incubation experiments techniques, and to implement a coordinated approach between all coastal and open ocean ESRs; JSI (M. Horvat/J.Kotnik), 1 months, M13, improvement and implementation of discrete DGM measurements (joint publication),HZG (C. Schrum, J. Bieser), 1 month, M32, to confront new observational data with models.


ESR 5

Project Title: MMHg sources in coastal ecosystem: new molecular and isotopic experimental speciation approaches.
Host: UPPA, Pau, France


Selected ESR: Alina Kleindienst

Supervisor: D. Amouroux
Co-supervisor: R. Guyoneaud (UPPA), C. Schrum (HZG)
Enrolment in Doctoral degree: Université de Pau et des Pays de l’Adour, France


Objectives:
(i) to investigate major microbial and photochemical processes connected to the formation of MMHg (and DMHg) in coastal marine ecosystems (Atlantic and Mediterranean coastal, shelf and/or margin stations), (ii) to understand the dynamic of MMHg formation/distribution from coastal to marginal marine areas in collaboration with ESR 4, 6, 7. ESR5 will collaborate with ESR3 on isotopic tracers incubation techniques, with ESR 7 on the role of coastal DOM, with ESR11 to test biosensor information and provide data for ESR13 for modelling purposes, and Collaboration with ESRs 3, 4, 6, 7, 11, 13.

Expected Results:
Methylation, di-methylation or demethylation rates at various depth andandand compartments of the water column as defined by critical biogeochemical parameters (e.g., microbial diversity and hgcA “methylation” genes; sunlight irradiance and DOM chromophoric properties) affecting Hg transformations in coastal, shelf and/or margin stations. Provide new molecular and isotopic information on the transformations pathways of the methylated Hg species in coastal environments (3 papers).

Planned secondments:
IOS/JSI (A. Lobnik, A. Lapanje), 1 month, , bioavailable fraction (biosensor) vs MMHg reactivity in coastal waters (combined with ESR11); SU (S. Jonsson), 2 months, the role of DOM in MMHg dynamics; HZG (C. Schrum, J. Bieser), 1 month, to make use of novel experimental data with models developed by ESR13 (joint paper – see D5.1).


ESR 6

Project Title: Uptake, bioconcentration and biomagnification of mercury into phyto- and zooplankton
Host: IFREMER, Nantes, France


Selected ESR: Isabel García Arévalo

Supervisor: J. Knoery
Co-supervisor: L.E. Heimbürger-Boavida (AMU), D. Point (CNRS)
Enrolment in Doctoral degree: University of Nantes, France


Context:
Seafood and especially marine fish are the primariy source of toxic monomethyl-Hg (MMHg) in Europeans.  However, the processes responsible for MMHg production within marine ecosystems remain poorly quantified an understood. Possible pathways include abiotic, microbial, and/or planktonic MMHg production. This ESR will study the role of marine particles, both living and non-living for marine MMHg production. All planned experiments are designe to mimic natural conditions as closely as possible and will be realized in mesocosms located at the Atlantic and Mediterranean coast.  Laboratory experiments may also be necessary.

Objectives and Methodologies:
The ESR will examine Hg and MMHg sorption and uptake rates onto/into a selection of marine particle types, including non-living particulate organic matter, microbes, phyto- and zooplankton. This work will be realized with dedicated, controlled experiments, both in the laboratory and in mesocosms at coastal sites. This ESR will use state-of-the-art techniques, including analytical isotope tracing methods, to deconvolute Hg and MMHg dynamics. In parallel the ESR will work on data from French Atlantic coastal field sampling campaigns.  The mesocosm and field studies will be conducted in collaboration with ESR4 and ESR7 to cover three contrasting environments and their land to sea continuums (Atlantic Ocean, Mediterranean and Baltic seas).

Expected Results:
Having generated original, new Hg speciation data and uptake rates between different marine particle size classes ranging from field-flow fractionated organic matter, bacteria- and phyto-, and zooplankton, the ESR will author 2 publications and contribute to a joint paper defined in D2.1.2.

Planned secondment(s):

With co-advisors: CNRS (D. Point), 2 months, isotope tracing analysis collaboration with ESR3 (joint paper); AMU (L. E. Heimbürger-Boavida), 1 month, to review, compare, and evaluate results obtained by ESR6 with data of ESR4;
With partners : HZG (J. Bieser), 1 month, to test newly obtained data within model developed by ESR13.


ESR 7

Project Title: The role of terrestrial Hg in coastal and open oceans.
Host: SU, Stockholm, Sweden


Selected ESR: Sonja Gindorf

Supervisor: S. Jonsson
Co-supervisor: E.Sunderland (Harvard), D. Amouroux (UPPA), L.E. Heimbürger-Boavida (AMU)
Enrolment in Doctoral degree: Stockholm University, Sweden


Context:
Biological uptake of inorganic Hg by bacteria (HgII) and monomethylmercury (MMHg) at the base of aquatic food web are critical steps in Hg’s biogeochemical cycle linking its sources to its inherent environmental risk. While primarily smaller dissolved complexes of Hg are available for biological uptake, most of the Hg in soil, sediment and inland waters is bound to particles and larger dissolved complexes. The bioavailability of HgII and MMHg in a natural system is therefore not obvious and, so far, under-studied. This project aims to understand availability of HgII and MMHg for biological uptake during transport from land to sea.

Objectives:
Gain improved understanding of the fate and reactivity of terrestrial Hg along land to sea transects by i) applying novel approaches to study refractory concentrations of Hg, ii) study the availability of Hg when complexes to dissolved organic matter (DOM) from terrestrial and marine environments for photochemical and bacterial transformation reactions, and biological uptake (sampling in e.g. Swedish Baltic coast, French Atlantic and Mediterranean coast and Northern Adriatic coasts, within the framework of ESR 4,5,6) and iii) comparison of experimental and field derived data on the availability of Hg-DOM complexes for biological uptake with the biological reactivity of Hg-DOM complexes measured using the biosensors (in collaboration with ESR 5 and 11), Collaboration with ESR 3, 5, 6, 11, 12, 13, 15

Expected Results:
Provide data on refractory concentration of Hg transported from the terrestrial compartment to coastal and open seas on particles and ii) the availability of Hg- and MeHg complexed with DOM extracted from contrasting land-to-sea transects and open ocean. (2 papers)

Planned secondments:
Tekran (E. Prestbo), 1 month, training on conventional analytical methods for Hg speciation; IJS/IOS (M. Horvat), 2 months, testing of new biosensor in laboratory setting and to apply biosensors to Hg-DOM extracts from experimental systems (ESR11); Harvard (E. Sunderland), 1 month, consideration of the obtained results in the modelling framework; HZG (C. Schrum, J. Bieser), 1 month, to make use of novel experimental data with models developed by ESR13.


ESR 8

Project Title: Release of mercury from thawing permafrost.
Host: SU, Stockholm, Sweden


Selected ESR: Charlotte Haugk

Supervisor: S. Jonsson
Co-supervisor: K. Gårdfeldt (SPRS) and D. Kocman (JSI)
Enrolment in Doctoral degree: Stockholm University, Sweden


Context:
In the recently published special IPCC report on The Ocean and Cryosphere in a Changing Climate it was concluded that permafrost temperatures have increased by 0.39 ± 0.15°C in zones with continuous permafrost during the last decade. Widespread accelerated permafrost thawing is predicted for this century and beyond. This threatens to remobilize large amounts of Hg currently ‘locked’ in Arctic permafrost soils to nearby lakes and estuaries and to the global biogeochemical cycle of Hg. Yet, future risk of Arctic Hg stocks is poorly understood. This project aims to unravel how a warmer climate can perturb the biogeochemical cycle of Hg and permafrost Hg stocks.

Objectives:
The ESR will study (i) to what extend Hg is mobilized to the atmosphere and downstream systems; (ii) if warmer climate and subsequent degradation of organic matter turns thawing permafrost soils into hotspots for Hg methylation, and (iii) what risk Hg in thawing permafrost pose for the local environment and for altering the global cycle of Hg. Field-work will be conducted at Abisko National Park in northern Sweden, Collaboration with ESRs 1, 3, 7, 9, 11, 12, 15

Expected Results:
Process based understanding of mobility and intercompartmental transformation processes of Hg stored in thawing permafrost (2 papers).

Planned secondment(s):
IJS/IOS (M. Horvat, A. Lapanje, D.Kocman), 2 months, testing of new biosensor in laboratory setting and to apply biosensors in experimental systems (ESR11) and collaborate with ESR9; CNRS (J. Sonke), 2 months, to get acquainted with experimental setup for determination of natural isotope abundance (collaboration with ESR1); CNR_IIA (N. Pirrone), 2-month, integration of the results into models (secondment together with ESR 12 and 15).  


ESR 9

Project Title: Terrestrial Hg pools inter-compartmental exchanges.
Host: JSI, Ljubljana, Slovenia


Selected ESR: Saeed Waqar Ali

Supervisor: D. Kocman
Co-supervisor: M.Horvat (JSI), E. Sunderland (Harvard), S. Jonsson (SU)
Enrolment in Doctoral degree: Jožef Stefan International Postgraduate School, Slovenia


Context:
Terrestrial Hg pools can act as both source and sink for atmospheric and aquatic Hg, respectively, its actual fate being driven by complex mechanisms and processes of retention, deposition and remobilization. Within the terrestrial compartment, the role of canopy and foliar exchange is especially understudied and potentially underestimated, although recent studies proposed that terrestrial vegetation might be responsible for controlling seasonal variations of atmospheric Hg. Therefore, an improved understanding of the role of vegetation in the global biogeochemical cycle of Hg and the underling controlling mechanisms are needed, supported by observations as well as integrated in respective models.

Objectives and expected results:
This project will focus on Hg in canopy and its interactions with atmosphere and aquatic systems. To this end  laboratory and filed experiments using novel analyitical techniques (supported by both radiotracers and measurements of stable Hg istopes) will be conducted and results  incorporated and upscaled in regional and global models using existing spatially-resolved datasets and available state-of-the art modelling tools.

Planned secondment(s):
SU (S. Jonsson), 2 months, acquaintance with analytical techniques for charactherisation of organic matter, UNEP/AMAP (S. Wilson, K. Davies) to explore potential of available global data sets; Harvard (E. Sunderland), 1 month, modelling of biogeochemical cycling of Hg in various environmental compartments; HZG (V. Matthias), 1 month, Integration of modelling approaches with those used within WP5.


ESR 10

Project Title: Traceability of Hg speciation measurements in the atmosphere.
Host: PSA, Greater London, UK


Selected ESR: Teodor-Daniel Andron

Supervisor: M. Horvat

Co-supervisor: W. Corns
Enrolment in Doctoral degree: JSI, Ljubljana, Slovenia


Context:
accurate and precise determination of Hg species in the atmosphere are required to understand the fate, transformation and global transportation of Hg. Currently, air monitoring networks are setup to determine total, particulate, oxidized and elemental forms of Hg. The accuracy of these measurements and integrity of sampling arrangements is currently in question as traceable calibration sources for each form of Hg at appropriate atmospheric concentration ranges have yet to be developed and installed in the field.

Objectives:
to develop, establish and implement a traceable calibration methodology for  oxidized Hg species;  to study, develop and compare different methods of measuring oxidized Hg; to accurately compare total Hg concentrations in generated standard gases for elemental Hg and oxidized Hg; to develop and evaluate optimal sampling procedures for particulate, oxidized and elemental Hg; to apply the developed methodologies to test and validate new and existing methods for on-line Hg measurement under field conditions. Collaboration with ESRs 1, 2, 7, 8.

Expected Results:
Validated calibration sources for Hg(0) and Hg(II) for low level gaseous Hg measurements. Expanded uncertainty budgets for atmospheric Hg speciation measurements. Validated and tested protocols applied at  observation stations and cruises,Figure 2. (2 papers).

Planned secondments:
VSL (I. Krom), 1 month, traceable calibration sources for Hg(0) and Hg(II); JSI, (M. Horvat), 2×2 months, training on Hg speciation using conventional techniques, calibration sources and testing, Lumex (S. Mashyanov), 1 month, direct testing of Hg(II) calibration device for Hg(II) using modified Lumex Zeeman AAS instruments.


ESR 11

Project Title: Innovative nano-biosensors detecting. MMHg
Host: IOS, Maribor, Slovenia


Selected ESR: Allwin Mabes Raj

Supervisor: A. Lobnik
Co-supervisor: A. Lapanje (JSI)
Enrolment in Doctoral degree: Jožef Stefan International Postgraduate School – JSIPS, Slovenia


Objectives:
The main objective is to understand the process of the sensor development which involves interdisciplinary topics and includes some knowledges from the material and nanomaterial science, photonics, chemicals, optical indicators as well biology. The main goal of this work is to design appropriate bio-chemical sensor for MMHg detection which should be on one hand very sensitive (to detect very low MMHg concentration), selective (to detect really MMHg and not other species) and on the other hand, very robust for direct measurement in the sea water. For sensor development close collaboration with ESRs 4, 5, 6, 7, 13 is needed.

Expected Results:
Sensor receptors will be designed by incorporation of optical indicators and biomolecules into various materials/nanomaterials. Sol-gel syntheses will be used to prepare appropriate nanomaterials for the incorporation of various indicator dyes as well biomolecules. For the development of biosensor receptor, synthetic biology circuit of directed evolution for proteins of high MMHg specificity will be designed. DNA and RNA biomolecules with high MMHg binding affinities will be obtained and characterised. Nanomayterials with immobilised optical indicators/biomolecules will be prepared and characterized (response time, reversibility, detection limits, operational lifetime, etc). (2 papers). The sensor receptor should be upgradet with the transducer part to prepare the sensor prototype. The sensor prototype for the MMHg detection will be tested in the laboratory and furthermore in the seawater. Nanosensor onsite testing is planned.

Planned secondments:
JSI (A. Lapanje), 2×2 months, process of coupling of biomolecules with nanomaterial and preparing prototype biosensor (joint paper); UPPA (D. Amouroux), 2 months, testing biosensor device in laboratory experiments implemented by ESR5; AMU (LE. Heimbürger_Boavida) and SU (S. Jonsson) timing aligned with the cruises and to provide access to obs-platforms for testing/implementation of novel Hg sensors ESR4 (joint paper on field testing).


ESR 12

Project Title: Regional 3D atmosphere  and ocean models to quantify the impact of oceanic sources on the regional Hg budget.
Host: CNR-IIA, Rome, Italy


Selected ESR: Prasad Shelke

Supervisor: N. Pirrone
Co-supervisor: I. M.Hedgecock (CNR), V.Matthias (HZG)
Enrolment in Doctoral degree: Jožef Stefan International Postgraduate School – JSIPS, Slovenia


Objectives:
To improve the modelling of Hg red-ox chemistry schemes in the atmosphere and implement exchange processes between the ocean and the atmosphere to facilitate the coupling between 3D atmospheric and oceanic models; to evaluate model updates using observational data and investigate the role of oceanic emissions; to investigate the impact of emission changes on Hg cycling in Europe. Collaboration with ESR1, 2, 4, 8, 9, 13, 14, 15.

Expected Results:
Updated Hg red-ox chemistry in regional models. Quantification of the impact of oceanic sources on observed Hg concentrations and on regional deposition patterns. Clarification to what extent reductions in anthropogenic Hg emissions will be visible in reduced atmospheric concentrations and depositions (2 papers).

Planned secondments:
HZG (J. Bieser), 2 months, Introduction to the computing infrastructure, the regional model COSMO-CMAQ, and model harmonization between ESR12 and ESR13. Development of evaluation cases with ESR14; UGA (A. Dommergue), 2 months, Improvement of the redox chemistry in regional model; the ESR will participate in the setup of laboratory experiments; HZG (J. Bieser), 2 months, finalising coupling protocols between models and coordination with ESR13 ocean/ecosystem model


ESR 13

Project Title: Modelling methylation and bio-accumulation of Hg in the marine environment.
Host: HZG, Geesthacht, Germany


Selected ESR: David Amptmeijer

Supervisor: C. Schrum
Co-supervisor: J. Bieser (HZG),  J. Knoery (IFREMER)
Enrolment in Doctoral degree: University of Hamburg, Germany


Objectives:
to generate a better understanding of methylation and bio-accumulation of Hg in the marine environment and implement this into parametrizations for 3D oceanic ecosystem models; to enhance our understanding of Hg accumulation in the food chain; to improve the regional ocean-ecosystem model MECOSMO and its validation with new observational data. Collaborating with ESR3, 4, 5, 6, 7, 11.

Expected Results:
Improved regional ocean-ecosystem model which can be used to evaluate the impact of emission changes in the Hg burden in sea food (2 papers).

Planned secondments:
UNEP, 1 week M15, Dissemination plan within the framework of the Minamata Convention; AMU (LE. Heimbürger), 2 months, M15-16, acquaintance with existing data on Hg speciation in the sea water; IFREMER (J. Knoery) 2 months M23-24, new data on bio-accumulation of Hg in phyto- and zoo-plankton; Harvard (E. Sunderland) 2 months, M32, collaboration with the improvement of the of the ocean-ecosystem model and comparison of global Hg ocean models.


ESR 14

Project Title: Exploration of long-term observational data sets to examine ocean/atmosphere exchange processes of Hg.
Host: HZG, Geesthacht, Germany


Selected ESR: Koketso Michelle Molepo

Supervisor: R. Ebinghaus
Co-supervisor: A.Dommergue (UGA), and N.E.Selin (MIT)
Enrolment in Doctoral degree: University of Hamburg, Germany


Context:
Long-term atmospheric data sets with high time resolution are existing for a globally increasing number of sites with the earliest ones starting already in 1995. These time series contain unique and useful but still underexplored information on the role of oceanic and terrestrial contributions to regional and global mercury budgets.

Objectives:
To investigate atmosphere-ocean Hg interactions by exploring long-term atmospheric Hg datasetsin order to improve the understanding of (i) ocean-atmosphere exchange processes and their effects on short- to long-term-scales, (ii) the role of the oceans in the global Hg budget and their source- vs. sink-function, (iii) (re-)construction of past emission data sets (iv) the ratio of anthropogenic vs. natural emissions, (v) the role of oceanic legacy re-emissions on a long-term perspective, (vi) the relevance of oceanic vs. terrestrial causes, such as SST vs. biomass burning (vi) the seasonality in emission based on long term data and emission inventories and source attribution). In collaboration with ESR1, 2, 4, 12, 15 an improved ocean atmosphere exchange parameterization of Hg will be implemented.

Planned secondment(s):
UGA (A. Dommergue), 1 month, M12, introduction to Amsterdam Island data sets and to field studies;; AMAP, 2 weeks M13 and JRC, 2 weeks M18 to learn about global inventory construction, together with ESR15; CNR-IIA (Hedgecock/Cinnirela), 1 months, M20, acquaintance with the GMOS data base and cyber infrastructure; MIT (N. Selin), 2 months, M31-32 to integrate novel field observations into global GEOS-CHEM 3D model, together with ESR1.


ESR 15

Project Title: Global Hg modelling to test scenarios and Hg reduction strategies.
Host: CNR-IIA, Rome, Italy


Selected ESR: Charikleia Gournia

Supervisor: N. Pirrone
Co-supervisor: N. E. Selin (MIT), V. Matthias (HZG)
Enrolment in Doctoral degree: Jožef Stefan International Postgraduate School – JSIPS, Slovenia


Objectives:
to develop modelling tools to simulate emission scenarios reflecting future Hg reduction policies on a global scale. To evaluate the impact of global emission changes in Europe. Collaboration with ESRs 1, 2, 4, 8, 9, 12,13, 14.

Expected Results:
Global emission perturbation runs that consider future reductions in line with the recommendation of the Minamata Convention. Validate models through an intercomparison exercise. Identify the source receptor relationship of Hg long-range transport for Europe. Demonstrate the impact of emission reductions on atmospheric concentrations and deposition and Hg concentrations in fish (2 papers) (in collaboration with ESR12-13-14).

Planned secondment(s):
EEB (E. Lambertini), 1 week, M9, planning for the NGO policy perspectives; UNEP, 1 week, M16, Dissemination plan within the framework of the Minamata Convention. HZG (J. Bieser), 1 month, Introduction to the computing infrastructure, and planning model harmonization between ESR12 and ESR13.; AMAP, 2 weeks M13, acquaintance with global inventories and release/emission estimate approaches. JRC, 2 weeks M18. Training on emission scenario development. MIT (N. Selin) & Harvard (E. Sunderland), 2 months M31-32 Global model comparison. The student will be trained to use the global multi-media model GEOS-Chem and perform a model inter-comparison.