Drought frequency and severity are expected to in-crease globally under projected climate change, with unknown consequences for hydrological and terrestrial ecosystems, while the terrestrial hydrological cycle is strongly linked to changing ecosystem processes. Current management tools, however, are based on the assumption of stationarity. To solve complex questions related to drought and ecosystems in a non-stationary world we need new hypotheses and new tools. Traditionally, the effects of drought on hydrolo-gy and vegetation are considered separately, despite the integral role of the terrestrial hydrological cycle in determining streamflow. This exciting PhD project proposes to answer the questions: (1) what are the driving meteorological conditions for streamflow drought and ecosystem impacts, (2) what is the rela-tionship between terrestrial and hydrological drought sensitivity, and (3) how does this relationship vary among vegetation types (grassland, forest, agricul-ture) and climates (precipitation/temperature gradi-ent)? Using a novel methodology, we propose to di-rectly compare hydrological drought sensitivity (measured by streamflow) and terrestrial drought sensitivity (measured by above ground net primary productivity, ANPP) via synthetic analysis of a number of experimental catchments where this data is availa-ble. This PhD project will work in Europe and North America by analysing and comparing various sites. The prospective sites in Europe are the Birmingham Insti-tute of Forest Research site in the UK (BIFOR, www.birmingham. ac.uk/research/activity/ bi-for/index.aspx), the Krycklan catchment in Sweden (www.slu.se/Krycklan; Figure 1), the Alzette River ba-sin in Luxembourg, and the TERENO network in Ger-many (teodoor.icg.kfa-juelich.de). For the North American sites we will make use of the LTER network. The goal is to investigate a large number of sites in order to quantitatively assess tradeoffs and synergies between hydrological and terrestrial drought sensitivi-ty across a climatic and ecosystem gradient. In a unique collaborative action, the results of this PhD project will then be compared between the European and North-American dataset with the aim to predict complex relationships between the ecosystem and (lack of) water under future climate change and vege-tation changes (a non-stationary world).
The methodology for this project will be developed in conjunction with our international partners and will draw from the experience of the supervisory team. For all of the sites, drought indices and hydrological and ecological drought sensitivity metrics will be calculated from generally available datasets of meteorological conditions (precipitation and potential evapotranspiration), streamflow observations and terrestrial ecosystem variables (net primary production). Terrestrial and hydrological drought sensitivity will be assessed separately; the relationship between the drought indices and the hydrological and ecological drought sensitivity metrics indicates how much of the interannual variability is explained by drought severity. Hydrological and terrestrial sensitivity will then be considered in tandem to assess the relationship between streamflow and ecosystem productivity.
Training and Skills
CENTA students are required to complete 45 days training throughout their PhD including a 10 day placement. In the first year, students will be trained as a single cohort on environmental science, research methods and core skills. Throughout the PhD, training will progress from core skills sets to master classes specific to the student's projects and themes.
This PhD offers unique opportunities to learn about different drought methods, novel data analysis tech-niques and ecohydrological processes. The PhD stu-dent will be embedded in the Drought Research Group at the University of Birmingham, which pro-vides training in R-programming, abstract and paper writing, presenting your scientific results, etc. The PhD student will have the possibility to exchange and in-teract with other PhD students in the framework of the recently launched doctoral training unit in hydro-logical sciences at the Luxembourg Institute of Science and Technology (www.list.lu/en/project/hydro-csi/). Additionally, the student is encouraged to attend the annual Krycklan summer school and symposium in Sweden. The link to our partners in North-America offers opportunities to visit dedicated workshops and conferences on the topic.
Year 1: The 1st year of the project will be devoted to getting to know the experimental catchments and collecting data from the study areas. Also the meth-odology developed in North America will be tested on the European data and possibly adapted.
Year 2: During the 2nd year of the project the data analysis will be performed on all sites and hypotheses will be tested.
Year 3: The 3rd year of the project focusses on combining and comparing the European results with the North-American dataset and writing research papers.
Partners and collaboration (including CASE)
The PhD project benefits from supervision by the world’s leading catchment-based ecohydrology and drought research groups. The School of Geography, Earth and Environmental Sciences at the University of Birmingham has a strong background in hydrological drought and ecohydrology, especially linked to the Birmingham Institute of Forest Research (BIFOR). McGill University (Canada), Uppsala University (Swe-den), and the Luxembourg Institute of Science and Technology (Luxembourg) are top-level institutes with expertise in terrestrial ecosystems, effects of climate change and hydrological extremes.
Applicants should have a background in a related field such as hydrology, ecology, earth sciences, me-teorology, geography. Good process understanding and programming experience are essential. Working experience with R would be beneficial. For further details please contact Anne Van Loon (firstname.lastname@example.org).