Ryan Williams

Polar Atmospheric Scientist

Ryan Williams

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Ryan Williams

Biography

Ryan Williams is currently a Polar Atmospheric Scientist, working on the NERC-funded ExtAnt project.

Ryan acquired both a BSc (Hons) in Physical Geography (2014) and MRes Science (2016) from the University of Portsmouth. In 2021, Ryan was awarded a PhD in Atmosphere, Oceans and Climate from the Department of Meteorology at the University of Reading, in producing his thesis on the regional and seasonal influences of the stratospheric contribution to tropospheric ozone. Ryan subsequently worked at ECMWF (2021) in evaluating the impact of a novel stratospheric ozone scheme upon forecast skill within their operational weather forecasting system, before working at BAS on the EU Horizon 2020 PolarRES project (2022-2023).

Whilst working on PolarRES, Ryan worked to construct and refine a set of climate storylines for the end-of-the-century over the Antarctic. Using of a large suite of climate models from CMIP6, plausible scenarios (storylines) were derived according to the amount of projected sea ice loss and strengthening of the stratospheric polar vortex simulated across the range of models. This approach helped to better understand the origins of the large model uncertainty across CMIP6 models and further our understanding of how climate change may manifest regionally across the Southern Hemisphere polar region.

Before starting on ExtAnt, Ryan worked in the Institute for Climate and Atmospheric Science at the University of Leeds. He investigated the role of the Northern Hemisphere strong stratospheric polar vortex during the winter 2021/22 on extratropical cyclone clustering that occurred over the North Atlantic during February 2022 as part of the NERC StratClust project. Through partnership with the Met Office, this influence was examined by analysing a series of sub-seasonal to seasonal hindcasts, including bespoke simulations in which the stratospheric dynamics are constrained to closely match the observed state.

Research interests

Atmospheric Dynamics

Climate Change

Extreme Events

Stratosphere-Troposphere Coupling

Chemistry-Climate Interactions

Polar Meteorology

Collaborations

Publications from NERC Open Research Archive

2024

Levine, Xavier J., Williams, Ryan S. ORCIDORCID record for Ryan S. Williams, Marshall, Gareth ORCIDORCID record for Gareth Marshall, Orr, Andrew ORCIDORCID record for Andrew Orr, Seland Graff, Lise, Handorf, Dörthe, Karpechko, Alexey, Köhler, Raphael, Wijngaard, René R., Johnston, Nadine ORCIDORCID record for Nadine Johnston, Lee, Hanna, Nieradzik, Lars, Mooney, Priscilla A.. (2024) Storylines of summer Arctic climate change constrained by Barents–Kara seas and Arctic tropospheric warming for climate risk assessment. Earth System Dynamics, 15 (). pp. 10.5194/esd-15-1161-2024

Williams, Ryan S. ORCIDORCID record for Ryan S. Williams, Marshall, Gareth J. ORCIDORCID record for Gareth J. Marshall, Levine, Xavier, Graff, Lise S., Handorf, Dörthe, Johnston, Nadine M. ORCIDORCID record for Nadine M. Johnston, Karpechko, Alexey Y., Orr, Andrew ORCIDORCID record for Andrew Orr, Van de Berg, Willem J., Wijngaard, René R., Mooney, Priscilla A.. (2024) Future Antarctic Climate: Storylines of mid-latitude jet strengthening and shift emergent from CMIP6. Journal of Climate, 37 (). pp. 10.1175/JCLI-D-23-0122.1

Williams, R.S. ORCIDORCID record for R.S. Williams, Hegglin, M.I., Jöckel, P., Garny, H., Shine, K.P.. (2024) Air quality and radiative impacts of downward-propagating sudden stratospheric warmings (SSWs). Atmospheric Chemistry and Physics, 24 (). 25 pp. 10.5194/acp-24-1389-2024

First Author

  • Williams, R. S., Hogan, R. J., Polichtchouk, I., Hegglin, M. H., Stockdale, T. & Flemming, J. (2021). Evaluating the impact of prognostic ozone in IFS NWP forecasts. ECMWF Technical Memorandum, 887, 10.21957/rakfo1qo3.
  • Williams, R. S., Hegglin, M. I., Kerridge, B. J., Jöckel, P., Latter, B. G. & Plummer, D. A. (2019). Characterising the seasonal and geographical variability in tropospheric ozone, stratospheric influence and recent changes. Atmospheric Chemistry and Physics, 19(6), 3589-3620, doi:10.5194/acp-19-3589-2019.

Co-Author

  • Levine, X., Williams, R., Marshall, G., Orr, A., Seland Graff, L., Handorf, D., Karpechko, A., Köhler, R., Wijngaard, R., Johnston, N., Lee, H., Nieradzik, L., and Mooney, P. (2023). Storylines of Summer Arctic climate change constrained by Barents-Kara Sea and Arctic tropospheric warming for climate risks assessment, EGUsphere [preprint], https://doi.org/10.5194/egusphere-2023-2741.
  • Pepin, N. C., Pike, G., Read, S. & Williams, R. (2019). The ability of moderate resolution imaging spectroradiometer land surface temperatures to simulate cold air drainage and microclimates in complex Arctic terrain. International Journal of Climatology, 39(2), 953-973, doi:1002/joc.5854.
  • Pepin, N. C., Maeda, E. E. & Williams, R. (2016). Use of remotely sensed land surface temperature as a proxy for air temperatures at high elevations: Findings from a 5000 m elevational transect across Kilimanjaro. Journal of Geophysical Research: Atmospheres, 121(17), 9998, doi:1002/2016JD025497.
  • Williams, R. & Thorp, T. (2015). Characteristics of springtime nocturnal temperature inversions in a high latitude environment. Weather, 70(S1), S37-S43, doi:1002/wea.2554.

ExtAnt

Investigating drivers and impacts of Antarctic weather extremes on the NERC-funded ExtAnt project. The project aims to exploit multiple datasets (in situ, reanalysis and model simulations) and statistical approaches to help understand the characteristics of extreme weather events (e.g., atmospheric rivers) both in the present-day and future climate. Cross-scale linkages will be examined on timescales ranging from hours to multi-decadal. A key focus is understanding how the localised (<15 km) evolution of extreme events, particularly over key vulnerable ice shelves along the coastal margin, relates to large-scale processes (e.g., teleconnections with remote regions such as the tropical Pacific).