Project description DEENESFRITPL Tree growth tracking to improve climate variability reconstruction Tree rings represent a fundamental archive for the high-resolution reconstruction of climate alterability over the past 1–2 ka at regional and global levels. Accurate reconstructions require a constant relationship between tree growth and climate. However, during the second half of the 20th century, tree-ring width and density chronologies were not able to track the rapidly increasing temperatures in Northern Hemisphere forests. This phenomenon, called the "divergence" problem, questions the reliability of tree-ring based temperature reconstruction and our understanding of the earth’s climate response to anthropogenic greenhouse gases. The EU-funded MONOSTAR project will develop a model that simulates year-to-year and long-term alterations in both the tree-ring width and density of varying conifer species growing under diverse climate environments. The model will be combined with data from a new hemispheric network of tree-ring width and density chronology as well as in situ monitoring data. Show the project objective Hide the project objective Objective Tree-rings are a key proxy archive for reconstructing high resolution climate variability over the past 1-2ka at regional to global scales. Skillful reconstructions require a stationary relationship between tree growth and climate (Hutton’s principle of uniformitarianism), which is commonly evaluated by statistical calibration/verification trials against instrumental measurements. This association, however, weakened during the second half of the 20th century, when tree-ring width and density chronologies from Northern Hemisphere forests were not able to track the rapidly increasing temperatures. This so-called “divergence” problem was identified in the 1990s to be a large-scale phenomenon, and not only questions the reliability of tree-ring based temperature reconstruction, but also affects our understanding of the Earth’s climate sensitivity to anthropogenic greenhouse gases. A conclusive explanation for this central problem of contemporary paleoclimate research is, however, still missing. Here, I propose to develop a process model that simulates year-to-year and long-term variations in both tree-ring width and density of different conifer species growing under different climate regimes. Evidence from this model will be combined with data from a new, hemispheric scale network of tree-ring width and density chronologies, as well as in-situ monitoring data, to train the model, validate synthetic timeseries, and analyze spatially varying influences of climatological, air chemical and ecological drivers on tree growth. Model-data fusion and inverse modelling techniques will be applied to quantify the non-linear mechanisms underlying divergence, and to deduce methodological recommendations that can be applied by any paleoclimatologist, working with different species and in different regions of the Northern Hemisphere, to mitigate late 20th century divergence and thus improve their climate reconstructions. Fields of science natural sciencesearth and related environmental sciencespalaeontologypaleoclimatologyagricultural sciencesagriculture, forestry, and fisheriesagriculturehorticulturearboriculturenatural sciencesearth and related environmental sciencesatmospheric sciencesclimatologyclimatic changes Programme(s) H2020-EU.1.1. - EXCELLENT SCIENCE - European Research Council (ERC) Main Programme Topic(s) ERC-2019-ADG - ERC Advanced Grant Call for proposal ERC-2019-ADG See other projects for this call Funding Scheme ERC-ADG - Advanced Grant Coordinator JOHANNES GUTENBERG-UNIVERSITAT MAINZ Net EU contribution € 2 497 500,00 Address Saarstrasse 21 55122 Mainz Germany See on map Region Rheinland-Pfalz Rheinhessen-Pfalz Mainz, Kreisfreie Stadt Activity type Higher or Secondary Education Establishments Links Contact the organisation Opens in new window Website Opens in new window Participation in EU R&I programmes Opens in new window HORIZON collaboration network Opens in new window Other funding € 0,00 Beneficiaries (1) Sort alphabetically Sort by Net EU contribution Expand all Collapse all JOHANNES GUTENBERG-UNIVERSITAT MAINZ Germany Net EU contribution € 2 497 500,00 Address Saarstrasse 21 55122 Mainz See on map Region Rheinland-Pfalz Rheinhessen-Pfalz Mainz, Kreisfreie Stadt Activity type Higher or Secondary Education Establishments Links Contact the organisation Opens in new window Website Opens in new window Participation in EU R&I programmes Opens in new window HORIZON collaboration network Opens in new window Other funding € 0,00
