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School of Geography

Jessica Baker Jessica Baker

Contact details

Room 8.12 Garstang
School of Geography
University of Leeds
University Road
Leeds LS2 9JT   UK



Project title

Reconstructing the Amazon hydrological cycle from oxygen isotopes in tree ring cellulose


The Amazon water cycle has strengthened in recent decades, with stronger wet season river flows and a widening gap between the amount of rainfall in the wet and dry seasons (Gloor et al., 2013).  Such changes may have important implications for the carbon stored in the basin, and thus for global climate (Gatti et al., 2014). To better understand what might be driving these changes in hydrology it is important to develop a good understanding of past climate in the region, although climate station data are scarce in the Amazon. Tree rings are an example of a natural climate record, with each ring recording information about the environment during the period of its formation. Oxygen isotopes in tree rings from northern Bolivia have been shown to be a good indicator of rainfall over the whole Amazon basin, and thus a useful tool for trying to reconstruct past climate (Brienen et al., 2012).


During this project I aim to further research into oxygen isotopes in tropical tree rings. I will explore variation in isotope signatures between different tree species and across multiple sites in the Amazon to see the extent to which signals are coherent in space and between species. Air parcel trajectory modelling will be used to try to better understand the factors driving isotope variation from year to year, an important requirement if tree ring oxygen isotopes are to be reliably used for reconstructing climate. Finally, I aim to develop a long (~200 years) annually-resolved isotope record, which should help us to understand recent climatic changes in the context of historic variability.




  • Baker, J.C.A.Gloor, M., Spracklen, D.V., Arnold, S.R., Tindall, J.C.Clerici, S. J., Leng, M.J. and Brienen, R. J. W., 2016What drives interannual variation in tree ring oxygen isotopes in the Amazon?Geophysical Research Letters43
  • Baker, J.C.A., Hunt, S.F., Clerici, S.J., Newton, R.J., Bottrell, S.H., Leng, M.J., Heaton, T.H., Helle, G., Argollo, J., Gloor, M. and Brienen, R.J., 2015. Oxygen isotopes in tree rings show good coherence between species and sites in Bolivia. Global and Planetary Change133, pp.298-308.
  • Gloor, M., Barichivich, J., Ziv, G., Brienen, R., Schöngart, J., Peylin, P., Cintra, L., Barcante, B., Feldpausch, T., Phillips, O. and Baker, J., 2015. Recent Amazon climate as background for possible ongoing and future changes of Amazon humid forests. Global Biogeochemical Cycles29(9), pp.1384-1399.

Research Affiliations

Ecology and Global Change


NERC Studentship


2012-2013 University College London: MSc Climate Change (Distinction)

2008-2011 University of Cambridge: BA (Hons) Natural Sciences (1st Class)