Sarah Perkins

Dr Sarah E Perkins
Research Associate, the ARC Centre of Excellence for Climate System Science
UNSW, Sydney, Australia

Sarah has been working at the CoECSS since November 2011. Prior to this, she was a research scientist for the Commonwealth Scientific and Industrial Research Organisation (CSIRO) in their marine and atmospheric research division.

Sarah’s research has held a firm focus on climate extremes. She has studied changes in temperature and precipitation extremes in observed and climate model data by applying various statistical methods such as generalised extreme value theory and climate indices. Although much of her work has concentrated on Australia, her time at CSIRO saw her analyse projected changes in climate for the Pacific region.

Her position at the CoECSS has seen Sarah concentrate on researching heat waves. Her paper recently published in Journal of climate seeks to constrain the large number of metrics used to measure heat waves. This paper also investigated changes in heat waves in the observational record over Australia. Sarah’s paper published in Geophysical Research Letters last year undertakes a similar analysis but for global observations.

Next, Sarah’s research will take her into furthering the understanding of what drives heat waves. Significant progress has been made worldwide on this subject, but there is still much to be done, particularly in the area of anthropogenic contribution. She also hopes to explore how heat waves are projected to change in the future, particularly in relation to the governing mechanisms.

Sarah is active on twitter (@sarahinscience) and is currently building her own webpage (www.sarahinscience.com) where she will blog about her work, public opinion on anthropogenic climate change, and what it’s like to be a climate scientist. Feel free to contact her about past, present and future work!


On the measurement of heat waves

Perkins, S. E., L. V. Alexander, 2013: J. Climate, 26, 4500–4517. doi: http://dx.doi.org/10.1175/JCLI-D-12-00383.1

Heat waves have devastating impacts on many human and natural systems. Because of the wide range of sectors impacted by these events, an extensive list of heat wave metrics exist, generally endemic to the study for which they were designed. In this study, Perkins and Alexander constrain this surplus of metrics by proposing that three different heat wave definitions, which are then analysed in terms of 5 separate characteristics, provide enough information on the intensity, frequency and duration of heat waves, suitable to most end-users.

They demonstrate the efficacy of this methodology by investigating changes in heat waves in the observational record over Australia.  Here they show that the strongest signal of change is in the number of heat wave days, yet there is little indication, at least for the time periods analysed, of significant changes in the intensity and number of events. There is, however, and indication that the hottest part of a heat wave is increasing faster than the mean magnitude, and that trends in all characteristics have accelerated in the latter 40 years of the 60- year time period analysed.

Perkins and Alexander will continue to use this methodology to understand changes in past, present and future heat waves over Australia and other global regions. The methodology has already been used to analyse changes in observed heat waves at the global scale, and is currently being implemented to further understand the drivers of heat waves over Australia, and future projections. It has also been included in the Expert Team for Climate Research and Sector Specific Climate Indices software, where end-users of climate data can calculate climate statistics on their own observational data.

Dr Sarah E Perkins Research Associate, the ARC Centre of Excellence for Climate System Science UNSW, Sydney, Australia