UCL Department of Geography


Sarah Roberts

My research is in aquatic contaminants and palaeolimnology. My current research is examining fossil-fuel combustion byproducts (spheroidal carbonaceous fly-ash particles) in environmental archives (lake, ice core, coral, marine, and peat records) across the globe. This work will help to inform the Anthropocene Working Group on the use of contaminant markers to define the onset of the Anthropocene epoch.

More about Dr Roberts

Previously I was a Research Scientist at Environment and Climate Change Canada (ECCC), working within the Aquatic Contaminants Research Division in Canada’s Centre for Inland Waters. My research assessed trends in atmospherically deposited contaminants (mercury and other metals) at both local level from freshwater lakes located nearby known point sources and in remote regions of Canada, and at a regional level. I also worked on research investigating bioaccumulation and biomagnification of contaminants in Canadian Arctic foodwebs.

Prior to this, I obtained my PhD at the University of Nottingham, where I investigated Lake Baikal's (the worlds largest freshwater lake by volume in Siberia) algal community response to recent anthropogenic pollution and environmental change over recent (~last 200 years) and longer (~last 1000 years) timescales.

I obtained a MSc in Quaternary Science (Distinction) from jointly Royal Holloway University of London and UCL, where I investigated diatom response to mid-Holocene climatic changes from Arctic lakes in the northernmost Peninsulas of Finnmark.


I teach on the following modules:


I also lead seminars and tutorial groups on the following modules:




  • Roberts, S., Kirk, J., Muir, D., Wiklund, J., Evans, M., Gleason, A., Tam, A., Drevnick, P., Dastoor, A., Ryjkov, A., Yang, F., Wang, X., Lawson, G., Pilote, M., Keating, J., Barst, B., Ahad, J., Cooke, C. 2021. Quantification of spatial and temporal trends in atmospheric mercury deposition across Canada over the past 30 years. Environmental Science & Technology, 55: (23) 15766-15775.
  • Swann, G.E.A., Panizzo, V.N., Piccolroaz, S., Pashley, V., Hortswood, M.S.A., Roberts, S., Vologina, E., Piotrowska, N., Sturm, M., Zhdanov, A., Granin, N., Norman, C., McGowan, S., Mackay, A.W. 2020. Changing nutrient cycling in Lake Baikal, the world's oldest lake. PNAS 1-7.
  • Chibwe, L., Roberts, S., Shang, D., Fan, Y., Manzano, C, Wang, X., Kirk, J.L., Muir, D.C.G. 2020. A one century sedimentary record of N- and S-polycyclic aromatic compounds in the Athabasca Oil Sands Region. Chemosphere 260: 1-9.
  • Dunnington, D., Roberts, S., Norton, S.A., Spooner, I.S., Kurek, J., Kirk, J.L., Muir, D.C.G., White, C.E., Gagnon, G.A. 2020. The distribution and potential impact of two centuries of lead deposition as recorded by lake sediments from northeastern North America. Science of the Total Environment 737: 1-10.
  • Roberts, S., Kirk, J.L., Wiklund, J.A., Muir, Derek, C.G., Keating, J., Yang, F., Gleason, A., Lawson, G., Evans, M. 2020. Sources of atmospheric metal(loid) pollution recorded in Thompson Manitoba lake sediment cores within the boreal Canadian shield. Science of the Total Environment 732: 1-12.
  • Roberts, S., Adams, J.K., Mackay, A.W., Swann, G.E.A., McGowan, S., Rose, N.L., Panizzo, V.N., Yang, H., Vologina, E.G., Sturm, M., Shchetniko, A.A. 2020. Mercury loading within the Selenga River Basin and Lake Baikal, Siberia. Environmental Pollution 259: 1-9.
  • Roberts, S., Kirk, J.L., Wiklund, J.A., Muir, Derek, C.G., Yang, F., Gleason, A., Lawson, G. 2019. Mercury and metal(loid) deposition to remote Nova Scotia lakes from both local and distant sources. Science of the Total Environment 675: 192-202.
  • Roberts, S., McGowan, S., Panizzo, V.N., Vologina, E.G., Mackay, A.W., Swann, G.E.A. 2018. Evidence of 21st Century ecosystem change in Lake Baikal, Siberia. PlOS One 13: (12), 1-20.
  • Panizzo, V.N., Roberts, S., Swann, G.E.A., McGowan, S., Mackay, A.W., Vologina, E.G., Pashley, V., Hortsworth, M.S.A. 2018. Spatial differences in spring dissolved silicon utilisation in Lake Baikal, Siberia: an example from an Aulacoseira baicalensis bloom. Limnology and Oceanography 63: 1562 – 1578.
  • Hampton, S.E., Galloway, A.W.E., Power, S.M., Ozersky, T., Woo, K.H., Batt, R.D., Labou, S.G., O’Reilly, C.M., Sharma, S., Lottig, N.R., Stanly, E.H., North, R.L., Stockwell, J.D., Adrian, R., Weyhenmeyer, G.A., Arvola, L., Baulch, H.M., Bertani, I., Bowman, L.L., Carey, C., Catalan, J., Colom-Montero, W., Domine, L.M., Felip, M., Granados, I., Gries, C., Grossart, H-P., Haberman, J., Haldna, M., Hayden, B., Higgins, S.N., Jolley, J.C., Kahilainen, K.K., Kaup, E., Kehoe, M.J., MacIntyre, S., Mackay, A.W., Mariash, H.L., McKay, R.M., Nixdorf, B., Nõges, B., Nõges, T., Palmer, M., Pierson, D.C., Post, D.M., Pruett, M.J., Rautio, M., Read, J.S., Roberts, S.L., et al. 2017. Ecology under lake ice. Ecology Letters 20: (1), 98 – 111.
  • Mackay, A.W., Seddon, A.W.R., Leng, M.J., Heumann, G., Morley, D.W., Piotrowska, N., Rioual, P., Roberts, S., Swann, G.E.A. 2017. Holocene carbon dynamics at the forest – steppe ecotone of southern Siberia. Global Change Biology 23: (5), 1942 – 1960.
  • Roberts, S., Jones, V.J., Allen, J.R.M., Huntley, B. 2015. Diatom response to mid-late Holocene climate in three small Arctic lakes in northernmost Finnmark. The Holocene 25: 911-920.

Assessment Reports

  • Kirk, J., Roberts, S. Chapter 3 Changes in Arctic mercury levels: emission sources, pathways and accumulation. Reconstruction of atmospheric Hg deposition using dated lake sediment cores in Arctic Monitoring and Assessment Programme (AMAP) Mercury Assessment Report 2021.
Research Interests
  • Environmental pollution
  • Palaeolimnology and limnology
  • Water quality monitoring and aquatic contaminants
  • Climate change impacts on aquatic ecosystems