ICICLES
Horizon2020 Marie Skłodowska Curie Actions Individual fellowship (MSCA-IF) "Iron and Carbon Interactions and Biogeochemical CycLing in Subglacial EcosystemS (ICICLES)"
Glaciers have been conventionally viewed as lifeless bodies that have little impact on biogeochemical cycles. It is now known that liquid water is present under all large ice masses. In Antarctica, subglacial lakes and rivers have been discovered. One of these subglacial lakes, Subglacial Lake Whillans, was accessed in 2013, and supports a diverse and metabolically active microbial ecosystem. This raises questions about biogeochemical cycling within these ecosystems. Specifically, the sources, concentrations, flows, modifications and interactions between life essential nutrients. The nutrients sourced from these environments might have an impact on downstream ecosystem productivity. This is of particular importance as the Southern Ocean, which surrounds Antarctica, is the world’s largest high nutrient low chlorophyll region, where iron is the primary limiting element for life. Organic matter is thought to play a major role in regulating the flux and bioavailability of iron, and may also be an important source of bioavailable carbon.
The main objective of ICICLES is to investigate the cycling and interactions between iron and carbon (as organic matter) in these unique environments. Iron and organic matter in waters and sediment samples from three sites at the bottom of the Antarctic Ice Sheet will be characterised using state-of-the-art spectroscopic and microscopic techniques. Diatom culturing using these samples will be used to determine potential iron bioavailability to downstream marine organisms, and the effects of organic matter complexation. A new budget of iron and organic matter export, and associated bioavailability, from the Antarctic Ice Sheet will be constructed and utilised with a global ocean model to postulate the impact of subglacial meltwaters on marine productivity. This combination of techniques will provide unprecedented insight into nutrient cycling in unique subglacial ecosystems, and the potential of ice sheets to fertilise surrounding oceans.
For more details, please contact Dr. Jon Hawkings.
Publications
(authors from the group in bold)
Hatton, J. E., Hendry, K. R., Hawkings, J., Wadham, J. L., Benning, L. G., Blukis, R., Roddatis, V., Ng, H. C., Wang, T. (2021): Physical weathering by glaciers enhances silicon mobilisation and isotopic fractionation. - Geochemical Perspectives Letters, 19, 7-12. https://doi.org/10.7185/geochemlet.2126
Hawkings, J., Linhoff, B. S., Wadham, J. L., Stibal, M., Lamborg, C. H., Carling, G. T., Lamarche-Gagnon, G., Kohler, T. J., Ward, R., Hendry, K. R., Falteisek, L., Kellerman, A. M., Cameron, K. A., Hatton, J. E., Tingey, S., Holt, A. D., Vinšová, P., Hofer, S., Bulínová, M., Větrovský, T., Meire, L., Spencer, R. G. M. (2021): Large subglacial source of mercury from the southwestern margin of the Greenland Ice Sheet. - Nature Geoscience, 14, 496-502. https://doi.org/10.1038/s41561-021-00753-w
Marshall, M. G., Kellerman, A. M., Wadham, J. L., Hawkings, J., Daneri, G., Torres, R., Pryer, H. V., Beaton, A., Ng, H. C., Urra, A., Robinson, L. F., Spencer, R. G. M. (2021): Seasonal Changes in Dissolved Organic Matter Composition in a Patagonian Fjord Affected by Glacier Melt Inputs. - Frontiers in Marine Science, 8, 612386. https://doi.org/10.3389/fmars.2021.612386
Hawkings, J., Skidmore, M. L., Wadham, J. L., Priscu, J. C., Morton, P. L., Hatton, J. E., Gardner, C. B., Kohler, T. J., Stibal, M., Bagshaw, E. A., Steigmeyer, A., Barker, J., Dore, J. E., Lyons, W. B., Tranter, M., Spencer, R. G. M. (2020): Enhanced trace element mobilization by Earth’s ice sheets. - Proceedings of the National Academy of Sciences of the United States of America (PNAS), 117, 50, 31648-31659. https://doi.org/10.1073/pnas.2014378117
Kellerman, A., Hawkings, J., Wadham, J., Kohler, T., Stibal, M., Grater, E., Marshall, M., Hatton, J., Beaton, A., Spencer, R. G. (2020): Glacier Outflow Dissolved Organic Matter as a Window Into Seasonally Changing Carbon Sources: Leverett Glacier, Greenland. - Journal of Geophysical Research: Biogeosciences, 125, 4, e2019JG005161. https://doi.org/10.1029/2019JG005161
Kohler, T. J., Vinšová, P., Falteisek, L., Žárský, J. D., Yde, J. C., Hatton, J. E., Hawkings, J., Lamarche-Gagnon, G., Hood, E., Cameron, K. A., Stibal, M. (2020): Patterns in Microbial Assemblages Exported From the Meltwater of Arctic and Sub-Arctic Glaciers. - Frontiers in Microbiology, 11, 669. https://doi.org/10.3389/fmicb.2020.00669
Pryer, H. V., Hatton, J. E., Wadham, J. L., Hawkings, J., Robinson, L. F., Kellerman, A. M., Marshall, M. G., Urra, A., Covey, A., Daneri, G., Häussermann, V., Hendry, K. R. (2020): The Effects of Glacial Cover on Riverine Silicon Isotope Compositions in Chilean Patagonia. - Frontiers in Earth Science, 8, 368. https://doi.org/10.3389/feart.2020.00368
Pryer, H. V., Hawkings, J., Wadham, J. L., Robinson, L. F., Hendry, K. R., Hatton, J. E., Kellerman, A. M., Bertrand, S., Gill‐Olivas, B., Marshall, M. G., Brooker, R. A., Daneri, G., Häussermann, V. (2020): The Influence of Glacial Cover on Riverine Silicon and Iron Exports in Chilean Patagonia. - Global Biogeochemical Cycles, 34, 12, e2020GB006611. https://doi.org/10.1029/2020GB006611
Hatton, J. E., Hendry, K. R., Hawkings, J., Wadham, J. L., Kohler, T. J., Stibal, M., Beaton, A. D., Bagshaw, E. A., Telling, J. (2019): Investigation of subglacial weathering under the Greenland Ice Sheet using silicon isotopes. - Geochimica et Cosmochimica Acta, 247, 191-206. https://doi.org/10.1016/j.gca.2018.12.033
Hatton, J. E., Hendry, K. R., Hawkings, J., Wadham, J. L., Opfergelt, S., Kohler, T. J., Yde, J. C., Stibal, M., Žárský, J. D. (2019): Silicon isotopes in Arctic and sub-Arctic glacial meltwaters: the role of subglacial weathering in the silicon cycle. - Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences, 475, 2228. https://doi.org/10.1098/rspa.2019.0098
Urra, A., Wadham, J., Hawkings, J., Telling, J., Hatton, J. E., Yde, J. C., Hasholt, B., van As, D., Bhatia, M. P., Nienow, P. (2019): Weathering Dynamics Under Contrasting Greenland Ice Sheet Catchments. - Frontiers in Earth Science, 7, 299. https://doi.org/10.3389/feart.2019.00299
Wadham, J. L., Hawkings, J., Tarasov, L., Gregoire, L. J., Spencer, R. G. M., Gutjahr, M., Ridgwell, A., Kohfeld, K. E. (2019): Ice sheets matter for the global carbon cycle. - Nature Communications, 10, 3567. https://doi.org/10.1038/s41467-019-11394-4
Raiswell, R., Hawkings, J., Elsenousy, A., Death, R., Tranter, M., Wadham, J. (2018): Iron in Glacial Systems: Speciation, Reactivity, Freezing Behavior, and Alteration During Transport. - Frontiers in Earth Science, 6, 222. https://doi.org/10.3389/feart.2018.00222