Luke James Harrington


    Qualifications

    BSc in Geophysics (Meteorology) & Environmental Science (VUW, 2012), BSc (Hons, 1st Class) in Physical Geography (VUW, 2013)

    PhD thesis

    Title

    Investigating the emergent physical response of extreme rainfall to anthropogenic climate change: a model- and process-based approach

    Supervisors

    David Frame, Sam Dean, James Renwick

    Project description

    Extreme weather events, particularly precipitation-related extremes such as flooding and droughts, can produce devastating socio-economic impacts. The latest projections from Working Group 1 of the fifth assessment report from the Intergovernmental Panel on Climate Change (IPCC) reveal that the likelihood of more frequent extreme rainfall events is set to increase in response to continued anthropogenic climate warming.

    There currently remains large uncertainties as to the physical mechanisms driving these extreme events. For example, previous research has assessed the expected changes to extreme precipitation as a thermodynamic response to increasing global temperatures (O’Gorman and Schneider 2009; Westra et al. 2013) However, quantifying the sensitivity of changes in precipitation extremes to corresponding temperature increases does not explain the dynamical pathways by which these changes will occur, and model deficiencies in simulating precipitation extremes currently represent a significant challenge to the modelling community (Stephens et al. 2010).

    In my project, simplified models will be developed to characterise the aggregated, emergent physical processes which contribute to extreme precipitation accumulations, with a particular focus on moisture flux anomalies. Model validation will be performed for a suite of state-of-the-art global climate models from the fifth phase of the Coupled Model Intercomparison Project (Taylor et al. 2012) and analysis of the anthropogenic contribution to global changes in these extreme rainfall indicators will be performed. Quantifying this link between moisture flux extremes and precipitation extremes will provide a basis for assessing the time of emergence of future changes to precipitation regimes globally, as well as a more refined assessment of the anthropogenic contribution to specific precipitation-related extreme events.

    Publications

    Peer-reviewed publications

    Harrington, L. J., S. M. Dean, D. J. Frame and M. Joshi, 2016: The role of meridional moisture flux anomalies in extreme coastal precipitation. Journal of Hydrometeorology (in preparation).

    Harrington, L. J., D. J. Frame, E. Fischer, E. Hawkins, M. Joshi and C. Jones, 2016: Poorest countries experience earlier anthropogenic emergence of daily temperature extremes. Environmental Research Letters, 11 (5), 055007.

    King, A. D., M. T. Black, S-K. Min, E. Fischer, L. J. Harrington, D. Mitchell, S. Perkins-Kirkpatrick, 2016: Emergence of heat extremes attributable to anthropogenic influences. Geophysical Research Letters, 43 (7), 3438-3443.

    Sippel, S., D. Mitchell, M. T. Black, A.J. Dittus, L. J. Harrington, N. Schaller and F. E. L. Otto, 2015: Combining large model ensembles with extreme value statistics to improve attribution statements of rare events. Weather and Climate Extremes, 9, 25-35. dx.doi.org/10.1016/j.wace.2015.06.004

    Harrington, L. J., S. Rosier, S. M. Dean, S. Stuart, and A. Scahill, 2014: The role of anthropogenic climate change in the 2013 drought over North Island, New Zealand [in “Explaining Extremes of 2013 from a Climate Perspective”]. Bulletin of American Meteorological Society, 95 (9), S45-S48

    Harrington, L. J., and J. Renwick, 2014: Secular trends in New Zealand rainfall characteristics 1950-2009. Weather and Climate, 34, 50-59.

    Non-peer reviewed articles

    Harrington, L.J. 2014: Science out in the cold. New Zealand Herald (10th September 2014)

    Seminars & conference presentations

    Harrington, L. J., D. J. Frame, E. Fischer, E. Hawkins, M. Joshi and C. Jones, 2016: Poorest countries experience earlier anthropogenic emergence of daily temperature extremes. University of Melbourne seminar series. Melbourne, Australia, 25th March 2016 (Oral).

    Harrington, L. J., S. M. Dean, D. J. Frame and M. Joshi, 2015: Future precipitation extremes are linked to changes in moisture flux anomalies. New Zealand Meteorological Society Conference 2015. Raglan, New Zealand, 23-25 November 2015. (Oral).

    Harrington, L. J., S. M. Dean, D. J. Frame and M. Joshi, 2015: Future precipitation extremes are linked to changes in moisture flux anomalies. 11th International Conference on Southern Hemisphere Meteorology and Oceanography (ICSHMO). Santiago, Chile, 5-9 October 2015. (Poster).

    Harrington, L. J., S. M. Dean, D. J. Frame and M. Joshi, 2015: Future precipitation extremes are linked to changes in moisture flux anomalies. Our Common Future under Climate Change. Paris, France, 7-10 July 2015. (Poster).

    Harrington, L. J., S. M. Dean, D. J. Frame and M. Joshi, 2015: Future precipitation extremes are linked to changes in moisture flux anomalies. International Union of Geodesy and Geophysics 26th General Assembly. Prague, Czech Republic, June 21 – July 2 2015. (Poster).

    Harrington, L. J., and J. Renwick, 2014: Secular trends in New Zealand rainfall characteristics 1950- 2009. New Zealand Meteorological Society Conference 2014. Wellington, New Zealand, 19-21 November 2014. (Oral).

    Harrington, L. J., S. Rosier, S. M. Dean, S. Stuart, and A. Scahill, 2014. The role of anthropogenic climate change in the 2013 drought over North Island, New Zealand. New Zealand Meteorological Society Conference 2014. Wellington, New Zealand, 19-21 November 2014. (Oral)

    Harrington, L. J., S. Rosier, S. M. Dean, S. Stuart, and A. Scahill, 2014. The role of anthropogenic climate change in the 2013 drought over North Island, New Zealand. WCRP-ICTP Summer School on the Attribution and Prediction of Extremes. Trieste, Italy, 23-31 July 2014. (Poster).