How will changing climate variability affect ecosystem resilience?

The University of Exeter’s College of Life and Environmental Sciencesis inviting applications for a fully-funded PhD studentship to commence in September 2018 or as soon as possible thereafter. For eligible students the studentship will cover UK/EU tuition fees plus an annual tax-free stipend of at least £14,777 for 3 years full-time, or pro rata for part-time study. The student would be based in the inter-disciplinary Earth System Science group in the College of Life and Environmental Sciences at the Streatham Campus in Exeter.

Location:

Geography, Streatham Campus, Exeter
Academic Supervisors:
Professor Tim Lenton, University of Exeter http://geography.exeter.ac.uk/staff/?web_id=Timothy_Lenton
Dr Hywel Williams, University of Exeter
http://emps.exeter.ac.uk/computer-science/staff/htpw201

Project Description:
There is widespread interest in the resilience, or otherwise, of natural and human systems subject to global changes, especially climate change. There is also a widespread stated desire from policymakers and other societal actors to increase the resilience of natural and human systems in the face of multiple global change stressors. However, despite theoretical progress, there is a paucity of work quantifying the resilience of different real world systems and monitoring whether it is changing over time. This is a critical gap, because if we cannot quantitatively measure resilience we cannot tell which systems are losing resilience, and we cannot tell whether societal efforts (e.g. policy interventions) to increase the resilience of particular systems are having the desired effect or not.
You will be part of a Leverhulme Trust funded project team undertaking the first systematic global scan of the resilience of the climate system and of a suite of marine and terrestrial ecosystems. This will further develop and apply methods of monitoring resilience that stem from previous work on early warning methods for tipping points [e.g. Lenton, 2011]. Your task will be to assess whether and how the resilience of specific ecosystems – including their likelihood of passing tipping points – is affected by changing climate variability [e.g. Boulton and Lenton, 2015]. The research will target locations where there are significant observed trends in both climate variability and ecosystem resilience. You will investigate whether and how climate variability drives ecosystem variability, for example, by integrating climate time-series (e.g. sea surface temperatures) and comparing to ecosystem time-series (e.g. plankton or fish abundance) in the same area [Di Lorenzo and Ohman, 2013]. This method will also be applied to spatio-temporal data, e.g. using maps of remotely sensed temporal variance in vegetation indices compared with rainfall or surface temperatures. You will also test for an effect of climate variability on ecosystem variability by e.g. looking across spatial gradient in climate variability for change in ecosystem variability whilst controlling for changes in absolute values of climate drivers (temperature, rainfall).
Looking ahead, climate models predict that several regions, e.g. the Amazon basin and Southern Africa will experience marked future increases in temperature variability, despite having negative or neutral trends up to now [Lenton et al., 2017]. You will identify and develop physical models for the ecosystem response to climate variability in these key regions, seek to calibrate them on observed responses to variability, and then use them to project the effects of future changes in climate variability on ecosystem resilience.
This award provides annual funding to cover UK/EU tuition fees and a tax-free stipend. For students who pay UK/EU tuition fees the award will cover the tuition fees in full, plus at least £14,777 per year tax-free stipend. Students who pay international tuition fees are eligible to apply, but should note that the award will only provide payment for part of the international tuition fee and no stipend.

Applicants for this studentship must have obtained, or be about to obtain, a First or Upper Second Class UK Honours degree, or the equivalent qualifications gained outside the UK, in an appropriate area of science or technology.
If English is not your first language you will need to have achieved at least 6.5 in IELTS and no less than 6.0 in any section by the start of the project. Alternative tests may be acceptable (see http://www.exeter.ac.uk/postgraduate/apply/english/).