Meet the scientists who contribute to the SPECIAL research group.
We are based in the Department of Geography and Environmental Science at the University of Reading.
Professor Sandy P. Harrison
Professor in Global Palaeoclimates and Biogeochemical Cycles
Sandy is a palaeoclimate diagnostician, using large-scale palaeoenvironmental data syntheses and various types of process-based models to study the interaction of climate and the terrestrial biosphere in the geologic past and the present day. The goal of her work is to use the mechanistic understanding of interactions developed under radically different climate of the past to improve our ability to predict the likely trajectory of future climate and environmental changes.
In addition to managing an dynamic research program, she is also active in numerous international organisations. As Co-Chair of the Palaeoclimate Modelling Intercomparison Project (PMIP) and as joint leader of the PMIP Data Working Group, she is committed to promoting the analysis and evaluation of the climate and earth-system models used for future projections. As Chair of the World Data System (WDS) of the International Science Council (ISC), she is working to ensure long-term sustainability of data stewardship worldwide.
Dr Laia Comas Bru
Postdoctoral Research Assistant – Palaeohydrological Data Analysis
Laia uses the geochemical characteristics of speleothems (cave formations) to infer past climate variability. These high-resolution records are used to examine the role of regional drivers in shaping local and regional climate conditions, as well as for climate model output evaluation.
She is the lead co-ordinator of the PAGES-sponsored SISAL (Speleothem Isotopes Synthesis and Analysis) working group, aimed at developing a global data synthesis of stable isotope records. Preliminary climate model evaluations using the SISAL database have been done as a Charlemont 2018 Scholar of the Royal Irish Academy. Laia is also in the PAGES Iso2k project aimed at investigating decadal to centennial-scale variability, as well as possible secular trends, in hydroclimate over the past 2,000 years.
Dr Mengna Liao
Postdoctoral Research Assistant
Mengna reconstructs past climate and environmental changes at a range of spatial scales by synthesising ecological, chemical, and physical data. She is also interested in the role of topography, geomorphology, and hydrology in controlling sedimentary processes in lake basins.
Her current work is based around the creation of the Global Lake Status Database v2 in conjunction with international colleagues. This resource facilitates data-model comparisons and the analysis of mechanisms of past climate and environmental changes. Her work uses lake basin characteristics to infer sedimentary processes and hydroclimate change in the Tibetan Plateau region, as well as examination of long-term patterns of landscape and ecosystem change in southeastern China.
Mengna also holds an on-going position at College of Chemistry and Life Sciences, Zhejiang Normal University, China.
Sean works in developing mathematical tools to find new ways to use, generate, and interpret climate data. His research interests include data assimilation in novel situations, linear algebra and numerics. His work also focuses on how data assimilation and vegetation modelling can be used to improve palaeoclimate reconstructions.
His current work involves improving upon pollen reconstructions of the Last Glacial Maximum and Mid-Holocene. Pollen reconstructions and outputs of climate models from the 3rd round of the Palaeoclimate Modelling Intercomparison Project are both fused together using a variational data assimilation technique. This creates complete, gridded and accurate maps of palaeoclimates. In the same process he uses vegetation models to correct for the impact of changing atmospheric CO2 concentration on pollen-derived reconstructions. Sean is currently studying for a NERC sponsored PhD in Mathematics at the University of Surrey as part of the SCENARIO DTP.
Esmeralda Cruz Silva
Esmeralda works with late Quaternary databases of pollen records at mid-latitudes. She uses this data to produce vegetation maps as a source of information about spatial dynamics of plant communities and climate through time.
Currently her PhD work is centred at reconstructing spatio-temporal changes of vegetation and climate in the Mediterranean region using Holocene pollen data from the EMBSeCBIO database, the European Pollen Database (EPD), the African Pollen Database (APD) and the Modern Pollen Data for Climate Reconstructions (SMPDS). As part of her research, she both developed from the literature and by SPECIAL group members to assess their robustness.
Alexander’s primary research interest is to investigate wildfire models and to improve their capacity to represent the ecological impacts of future wildfire changes. He is also interested in investigating whether controls on wildfire vary regionally, and how this is represented by different fire models.
Currently, He is working on analysing the relationship between burnt area and different biophysical variables and other variables, such as above ground biomass. He is using the INFERNO3 global fire model in perturbed-parameter experiments in order to help address the above questions.
Alexander is currently studying for a QMEE PhD at Imperial University
Sarah investigates monsoon dynamics over the Holocene period (the last 12,000 years) using palaeoclimate records of hydrological change, including speleothem and lake-level data. Her research involves the analysis and comparison of these records to reconstruct changes in the extent and magnitude of northern and southern hemisphere monsoons, and comparison of these reconstructions with climate models.
Currently, her work is focused on reconstructing the spatio-temporal evolution of regional monsoons using oxygen isotope data from speleothems, utilising the SISAL (speleothem isotope synthesis and analysis) database. By comparing speleothem-based palaeoclimate observations with climate model simulations, the forcing mechanisms and internal interactions controlling monsoon evolution can be investigated.
Mark examines rapid climate change and its effect on vegetation using pollen accumulations in lake sediments. He examines modern pollen assemblages and uses the relationships between pollen and climate to infer changes in climate variables through time.
His current work focuses on the last glacial (~20,000 years ago to ~120,000 years ago). During this time, there are at least 20 periods of rapid temperature increases (Dansgaard-Oeschger cycles) with similar rates of change to what the world is currently experiencing. Pollen assemblages in lake sediments reflect these changes, and the modern pollen-climate relationships may be used to quantitatively reconstruct climate changes during these events. This work helps in answering questions about the fate of vegetation under current and future climate change.
Kamolphat Atsawawaranunt (A)
Scientific Programmer & Data Manager
A constructs and manages databases within the group. These include the SISAL (Speleothem Isotopes Synthesis and Analysis) and GLSDBv2 (Global Lake Status Database version 2) database. The SISAL database is a global compilation of stable isotope records from speleothems and the GLSDBv2 database contains semi-quantitative information of lake level statuses through time. The first version of the SISAL database is currently available (check the Resources section) and GLSDBv2 is currently being constructed. He also manages other on-going databases that are used within the group such as EMBSecBIO and other pollen databases. He also writes scripts to check the data integrity before the data is stored in the database. He also manages the scripts and data used within the group and help with analyses and processing of data when required.
Previous Team Members
Bronwyn examines the range of natural climate variability across seasonal to millennial time scales by synthesising multiple lines of palaeoclimate evidence from lake cores and speleothems (cave formations). Her research interests include the incorporation of modern climate data to improve palaeoclimate reconstructions, and the role of hemispheric circulation patterns in explaining climate variability on local and regional scales.
Her current work focuses on the reconstruction of Australian rainfall during the Last Glacial Maximum (approx. 22,000 years ago) and through the Holocene (the last 10,000 years), as a part of the Global Lake Status Database v2. Hydroclimate variability over this time period can be inferred from sedimentary, geochemical, and ecological data from sediment cores collected from lake basins. She is also the Oceania representative for the PAGES-funded SISAL (Speleothem Isotopes Synthesis and Analysis) working group.
Dr Guangqi Li
Li explores present and past tree ring behaviour in innovative and creative theory-based approaches. His research interests include tree ring growth mechanisms and modelling, the use of tree rings in palaeoclimate reconstructions, and the use of tree rings in climate data-model comparison.
His current work applies these themes to the last millennium in the Northern Hemisphere. Tree ring characteristics can be examined for known warm (i.e. the Medieval Warm Period) and cool (i.e. the Little Ice Age) periods and known forcings (i.e. volcanic events, solar radiation) during this time. The agreement between the patterns suggested by tree rings and those suggested by climate models can be used to assess the performance of various climate models.
Nick reconstructs high resolution environmental change from varved lakes in Mexico and Turkey through the Holocene. Through the analysis of varve microfacies, he examines the dynamics and drivers of limnological change within these lakes, and explores the potential relationship between environmental and societal change.
As part of the team developing the Global Lake Status Database v2, his work currently focuses on reconstructing past lake level change from lacustrine records within Central America and the Caribbean. This regional (and global) synthesis of lake hydrology provides an insight into the spatio-temporal variability of region’s hydroclimate through the Late Pleistocene and Holocene. By analysing this database, and comparing its output with global climate models, the precise mechanisms driving key hydroclimatic changes may be identified.
Dongyang examines the relation between vegetation and bioclimatic variables based on surface pollen and climate data using data quantitative approaches and mathematic models. She reconstructs paleoclimate via fossil pollen record in lake sediments. Her research interest involves climate models, palaeoclimate and ecology.
Her current work is focused on reconstructing climate and vegetation changes in semi-arid Spain from the Last Interglacial (~130,000 yr BP) to the recent times and improving the paleoclimate reconstruction method. Meanwhile, she analyses the multiple climatic causes of the distribution of forest, woodland, shrubland and savanna vegetation types in Spain, using extended European surface pollen sample data set, covering the whole Europe, Central Asia and Middle East.