Research group: Empirical Inference of the Earth System
Mission | Team | Projects | Publications
Revealing insights from observations by means of data-driven research is a key element in Earth system sciences. Long-term observations of multiple Earth system properties encode our knowledge on how land-surface processes respond to climatic variability and interact with biodiversity. We develop methods to extract the valuable information in these data. We aim at a more profound understanding of changing land ecosystems and their responses to and interactions with climate anomalies.
We are an interdisciplinary team of scientists contributing expertise in "Biology", "Ecology", "Geography" (or should we say "Earth System Science"?), "Computer Science" and "Physics".
Currently our group is following four core topics (a detailed description will follow soon):
- The emerging Earth system data cube
- Extremes and anomalies in the terrestrial biosphere
- Biogeography and ecosystem functioning
- Data analytic methods
- From observations to models
From left to right: Jannis, Milan, Julia, Guido, Fabian, Paul, Sebastian, Talie, Miguel, Iulia, Rocio
News and events
Mai 2017: Sebastian defended his PhD thesis @ ETH, congratulation!
We are very happy that Sebastian finished his PhD thesis on Climate extremes and their impact on ecosystem–atmosphere interactions in a very impressive defense at the ETH Zürich. Congratulations from the entiere team - we are proud of you. From left to right: Martin Heimann, Niki Gruber, Sebastian Sippel, Sonia Seneviratne, Miguel Mahecha.
April 2017: Workshop on Using the Earth System Data Cube: Status and Future
In these days we are about to finalize the CAB-LAB project (more known as the “Earth System Data Cube”) and will have a small Final Workshop that will be held at ESRIN, Frascati (Italy) on 12th April, 2017.
The aims of this Workshop are
- To present what has been achieved so far regarding building the Earth System Data Cube (from an infrastructural point of view),
- To present the scientific avenues we have been exploring,
- To discuss how the community evaluates the potential of the project for the future,
- To discuss new use-cases that can be addressed in future work.
More details about the meeting will be added here soon
Jan 2017: No evidence for increasing precipitation extremes and annual totals in the world's dry regions!
Recently we tried to publish a comment on a Nature Climate Change paper that received a lot of attention, but uses very problematic statistical approaches. However, we were not allowed to publish our critique in the very journal despite of reviewers acknowledging that there were issues in the paper. But, as we consider the topic a very important one it needs to be based on robust analytics. Consequently, we submitted our comment to another journal: Hydrology and Earth System Sciences. Here, again, the reviews were very positive (all can be seen in the discussion forum) and now the final paper is accepted and was published these days:
Sippel, S,, Jakob Zscheischler, Heimann, H., Lange, H., Mahecha, M.D., van Oldenborgh, G.J., Otto, F.E.L. & Reichstein, M. Have precipitation extremes and annual totals been increasing in the world's dry regions over the last 60 years? Hydrolgy and Earth System Sciences, 21, 441-458, doi:10.5194/hess-2016-452.
Fig (right): Trends and 30-year means of spatially aggregated heavy precipitation (Rx1d) in dry and transitional regions combined (Greve et al., 2014). Grey lines indicate our estimation using an aridity-based dryness definition and correcting for statistical artefacts, black lines are estimated equally, but after removing cases of incomplete temporal coverage. All p-values are given for two-sided (one-sided) Mann-Kendall trend tests.
Jan 2017: Older and more diverse forests have a stable photosynthetic capacity
In tandem, vegetation and soils serve as global "bioreactors" that constantly take‐up and release CO2. The intensity of this "natural pump" partly shapes the atmospheric concentrations of CO2. However, this is a fragile process i.e. climate extremes and variability can affect it substantially. Consequently, many scientists are seeking to understand which factors are stabilizing the key
ecosystem processes such as its capacity to take up CO2 over the years. Writing in the newly launched journal Nature Ecology and Evolution, Talie from our team and coworkers across the world investigate the capacity of forests to dampen the effect of climate variability on the natural CO2 pump. Two factors seem to clearly control this "buffer": Forest age and its species diversity. This finding can be read as a scientific call to preserving old forests and their diversity order to stabilize their functionality! Congrats to this nice success... For more information please go to: Go to the publishers page!
Jan 2017: EGU session submission - Information extraction from satellite Earth observations using data-driven methods
The unprecedented volumes of satellite Earth observation data gathered today allow for thorough investigation of Earth's climate system and its interactions with the biosphere. Several international research initiatives and scientific projects are focused on the application of mathematical and statistical methods to extract insights about the functioning of the hydrosphere, biosphere and atmosphere, from this emerging Earth information data-cube. However, this data-cube is highly dimensional, thus innovative data mining and big data tools are required, and machine-learning methods – such as neural networks, tree ensembles, random forests or Gaussian processes, among others – can offer new means to extract valuable information in a rigorous manner. This session aims to bring researchers together to discuss the current state in big data and machine learning applications to Earth sciences and remote sensing. We encourage authors to submit presentations on: machine learning applied to geosciences and remote sensing, data-driven methods to analyse spatiotemporal dynamics and causal relationships in Earth observations, enlightening opinions about interface between mathematics and climate science. Submit an abstract!
December 2016: Our contributions to the AGU fall meeting
November 2016: Project workshop in Colombia
A 50 year-old armed conflict in Colombia has influenced natural landscapes and their conservation status both positively and negatively. It remains unclear whether the ongoing conflict resolution would promote drastic changes in land-use promoting either deforestation or conservation. Recent and projected changes in climate constitute a further threat for the conservation of the fragile ecosystems in the country through potential increases in the recurrence rates and intensities of droughts, floods, fires, among other phenomena. This situation makes it crucial to develop an ecological observatory system (EOS) for assessing changes in biodiversity and ecosystem functioning in Colombia. A first meeting developed a discussion forum with diverse experts to explore the possibility of implementing an ecological observatory system for Colombia. Various activities are planned now and will be realized in 2017 and beyond with key scientific units in the country. We are heavily involved since the early planning stage and committed to further develop this activity. For more info: http://www.bgc-jena.mpg.de/EOS/ Funded by the BMBF and ESA-iLEAPS.
October 2016: We have a few new papers in open access discussion - showing the diversity of our topics
|+Ilie, I., Dittrich, P., Carvalhais, N., Jung, M., Heinemeyer, A., Migliavacca, M., Morison, J.I.L., Sippel, S., Subke, J.-A., Wilkinson, M. and Mahecha, M.D. Reverse engineering model structures for soil and ecosystem respiration: the potential of gene expression programming. Geoscientific Model Development - Discussions, doi:10.5194/gmd-2016-242.|
|+Flach, M., Gans, F., Brenning, A., Denzler, J., Reichstein, M., Rodner, E., Bathiany, S., Bodesheim, P., Guanche, Y., Sippel, S., and Mahecha, M.D. Multivariate Anomaly Detection for Earth Observations: A Comparison of Algorithms and Feature Extraction Techniques. Earth System Dynamics - Discussions, doi:10.5194/esd-2016-51.|
|+Sippel, S., Zscheischler, J., Mahecha, M.D., Orth, R., Reichstein, M., Vogel, M., Seneviratne, S.I. Refining multi-model projections of temperature extremes by evaluation against land–atmosphere coupling diagnostics. Earth System Dynamics - Discussions, doi:10.5194/esd-2016-48.|
|+Zscheischler, J., Mahecha, M.D., Avitabile, V., Calle, L., Carvalhais, N., Ciais, P., Gans, F., Gruber, N., Hartmann, J., Herold, M., Ichs, K., Jung, M., Landschützer, P., Laruelle, G.G., Lauerwald, R., Papale, D., Peylin, P., Poulter, B., Ray, D., Renier, P., Rödenbeck, C., Roman-Cuesta, R.M., Schwalm, C., Tramontana, G., Tyukavina, A.T., Valentini, R., van der Werf, G., West, T.O., Wolf, J.E., Reichstein, M. An empirical spatiotemporal description of the global surface-atmosphere carbon fluxes: opportunities and data limitations. Biogeosciences - Discussions, doi:10.5194/bg-2016-427.|
|+Sippel, S., Zscheischler, J., Hermann, M., Lange, H., Mahecha, M.D., Van Oldenburg, G.J., Otto, F.E.L., Reichstein, M. Have precipitation extremes and annual totals been increasing in the world's dry regions over the last 60 years? Hydrology and Earth System Sciences - Discussions, doi:10.5194/hess-2016-452.|
September 2016: MSCJ Autumn School co-organized by the group
August 2016: Very nice paper resulting from our collaboration with the Functional Biodiversity group accepted
Musavi, T., Migliavacca, M., van de Weg, M.J., Kattge, J., Wohlfahrt, G., van Bodegom, P.M., Reichstein, M., Bahn, M., Carrara, A. F. Domingues, T.F., Gavazzi, M., Pianelle, D., Gimeno, C., Granier, A., Gruening, C., Havránková, K., Herbst, M., Hrynkiw, C., Kalahari, A., Kaminski, T. Klump, K., Kolari, P., Longdog, B., Miners, S., Montanan, L., Moors, E., Ocher, W.C., Reich, P.B., Rohatyn, S., Rossi, A., Rosenberg, E., Varlagin, A. Wilkinson, M., Wirth, C., & Mahecha, M.D. (2016) Potential and limitations of inferring ecosystem photosynthetic capacity from leaf functional traits. Ecology and Evolution. doi:10.1002/ece3.2479.<?
Fig. to the right: Relationship between ecosystem photosynthetic capacity and community weighted N%. In a) we extracted data from two global data bases, in b) we used in-situ data for N%, and in c) both axis were sampled synchronously in space and time. Colors represent different vegetation types.
February 2016: Workshops at the on Extreme Events and Environments from Climate to Society (E3S)
January 2016: Jakob receives the Köppen award for his excellent PhD that he realized in our group! Congrats - we are proud!
We are proud of Jakob Zscheischler (now at the ETH Zürich), who receives the Wladimir-Peter-Köppen-Preize awarded by the Cluster of Excellence "Integrated Climate System Analysis and Prediction" (CliSAP) at the University of Hamburg. The thesis was realized in our group and submitted to the Swiss Federal Institute of Technology Zurich (ETH) in 2014. Please find more information here and here or simply see his key papers listed below. One of the key findings of the thesis was that few extremes in gross primary production can largely explain the inter annual variability of this very process. See for instance this paper Zscheischler, J., Mahecha, M.D., von Buttlar, J., Harmeling, S., Jung, M., Rammig, A., Randerson, J., Schölkopf, B., Seneviratne, S.I., Tomelleri, E., Zaehle, S. and Reichstein, M., (2014) Few extreme events dominate global interannual variability in gross primary production. Environmental Research Letters 9 035001.
Fig. to the right: Award ceremony at the MPI for Meteorology, Hamburg.
January 2016: Sebastian explains his latest research in a prominent online blog! ...
Sebastian had the opportunity to explain his important research on the question "How to quantify changes in climate extremes without inducing artifacts?" in a prominent blog here. We hope that this piece of work will reach many interested researchers. Interested? Please check out the original paper as well: Sippel, S., Zscheischler, J., Heimann, M., Otto, F.E.L, Peters, J. & Mahecha, M.D. (2015) Quantifying changes in climate variability and extremes: pitfalls and their overcoming. Geophysical Research Letters, 42, 9990--9998, doi:10.1002/2015GL066307/.
Fig. to the right: Biases in the detection of extreme events in stationary and independent Gaussian data induced by normalization. (a) Occurrences of + two-sigma extremes in artificial Gaussian time series (10.000 replicates) before normalizing the data (black line) and after normalizing each replicate using the first 30 samples as reference period. (b) Variance inflation and reduction through the generation of anomalies in the out-of-base (blue) versus reference period (red) probability density function (PDF) (nref = 8 for illustration). (c) Changing tails in normalized (i.e., divided by the SD estimate) Gaussian variables (nref = 8 for illustration).
November 2015: We hosted a very nice workshop on Exploring the Earth System Data Cube
Across Europe (and elsewhere), many scientists are working on the question of how to simultaneously explore multiple Earth Observations (EOs).
This endeavour involves applying novel statistical and data mining tools to explore the archives of existing EOs and inform the development of upcoming ones. The focal topic for this CAB-LAB workshop is co-interpreting EOs for their capacity to extract longer-term transformations and represent impacts of extreme anomalies on land ecosystems. This is a pressing scientific challenge, currently being tackled on many fronts. Participants are invited from across this diverse community to explore the issues together.
Please follow this link to a full workshop description for a full description.
Phone: +49.3641.57 - extension | E-mail: e-mail - at - bgc-jena.mpg.de
|| * co-oriented by BGI & Jens Kattge
|| ** co-oriented by Mirco Migliavacca
Former Team Members and Guests
| Franziska Schrodt
|| Now at the University of Brighton
| Iulia Ilie
|| PhD Student
| Jakob Zscheischler
|| PhD Student, later PostDoc
|| Now at the ETH Zürich
| Reik Donner
|| Now at PIK
| Xiuchen Wu
|| Now at the Beijing Normal University
| Chao Ting Chang
|| Visitor (2012 & 2013)
|| CREAF, Universitat Autonoma de Barcelona
| Lina Fürst
|| Master Student
|| Now at the University of Bayreuth
| Jannis von Buttlar
|| PhD Student, guest
Our current key projects
Publications by research area
Note, here we only show the papers where a group member is first or senior author. Follow this link for a complete list of publications produced since 2013 by this research group.
Extremes & Anomalies in the terrestrial biosphere
- Sippel, S,, Forkel, M., Rammig, A. Thonicke, K., Flach, M., Heimann, M., Otto, F. Reichstein, M. & Mahecha, M.D., (accepted) Contrasting and interacting changes in simulated spring and summer carbon cycle extremes in European ecosystems Environmental Research Letters.
- Sippel, S,, Zscheischler, J., Heimann, H., Lange, H., Mahecha, M.D., van Oldenborgh, G.J., Otto, F.E.L. & Reichstein, M. (2016) Have precipitation extremes and annual totals been increasing in the world's dry regions over the last 60 years? Hydrology and Earth Syststem Science Discussussion, doi:10.5194/hess-2016-452.
- Flach, M., Gans, F., Brenning, A., Denzler, J., Reichstein, M., Rodner, E., Bathiany, S., Bodesheim, P., Guanche, Y., Sippel, S. & Mahecha, M.D. (2016) Multivariate Anomaly Detection for Earth Observations: A Comparison of Algorithms and Feature Extraction Techniques. Earth System Dynamics - Discussions, doi:10.5194/esd-2016-51.
- Sippel, S,, Zscheischler, J. & Reichstein, M. (2016) Ecosystem impacts of climate extremes crucially depend on the timing. Proceedings of the National Academy of Sciences, 113, 5768-5770, doi:10.1073/pnas.1605667113.
- Ramming, A. & Mahecha, M.D. (2015) Ecology: Ecosystem responses to climate extremes. Nature, 527, 315-316, doi:doi:10.1038/527315a.
- Sippel, S., Zscheischler, J., Heimann, M., Otto, F.E.L, Peters, J. & Mahecha, M.D. (2015) Quantifying changes in climate variability and extremes: pitfalls and their overcoming. Geophysical Research Letters, 42, 9990-9998, doi:10.1002/2015GL066307.
- Zscheischler, J., Mahecha, M.D., von Buttlar, J., Harmeling, S., Jung, M., Rammig, A., Randerson, J., Schölkopf, B., Seneviratne, S.I., Tomelleri, E., Zaehle, S. & Reichstein, M., (2014) Few extreme events dominate global interannual variability in gross primary production. Environmental Research Letters, 9, 035001, doi:10.1088/1748-9326/9/3/035001.
- Reichstein, M., Bahn, M., Ciais, P., Frank, D., Mahecha, M.D., Seneviratne, S.I., Zscheischler, J., Beer, C., Buchmann, N., Frank, D.C., Papale, D., Rammig, A., Smith, P., Thonicke, K., van der Velde, M., Vicca, S., Walz, A. & Wattenbach, M. (2013) Climate extremes and the carbon cycle. Nature, 500, 287–295, doi:10.1038/nature12350.
- Zscheischler, J., Mahecha, M.D., Harmeling, S. & Reichstein, M. (2013) Detection and attribution of large spatiotemporal extreme events in Earth observation data. Ecological Informatics, 15, 66–73, doi:10.1016/j.ecoinf.2013.03.004.
Biogeography and ecosystem functioning
- Musavi, T., Migliavacca, M., Reichstein, M. Kattge, J., Wirth, C., Black, T.A., Janssens, I., Knohl, A., Loustau, D., Roupsard, O., Varlagin, A., Rambal, S., Cescatti, A., Gianelle, D., Kondo, H., Tamrakar, R. & Mahecha, M.D. (2017) Stand age and species richness dampen interannual variation of ecosystem-level photosynthetic capacity. Nature Ecology & Evolution, 1, 0048, doi:10.1038/s41559-016-0048.
- Musavi, T., Migliavacca, M., van de Weg, M.J., Kattge, J., Wohlfahrt, G., van Bodegom, P.M., Reichstein, M., Bahn, M., Carrara, A. F. Domingues, T.F., Gavazzi, M., Pianelle, D., Gimeno, C., Granier, A., Gruening, C., Havránková, K., Herbst, M., Hrynkiw, C., Kalahari, A., Kaminski, T. Klump, K., Kolari, P., Longdog, B., Miners, S., Montanan, L., Moors, E., Ocher, W.C., Reich, P.B., Rohatyn, S., Rossi, A., Rosenberg, E., Varlagin, A. Wilkinson, M., Wirth, C. & Mahecha, M.D. (2016) Potential and limitations of inferring ecosystem photosynthetic capacity from leaf functional traits. Ecology and Evolution, 6, 7352–7366, doi:10.1002/ece3.2479.
- Musavi, T., Mahecha, M.D., Migliavacca, M., Reichstein, M., van de Weg, M.J., van Bodegom, P.M., Bahn, M., Wirth, C., Reich, P.B., Schrodt, F., & Kattge, J. (2015) The imprint of plants on ecosystem functioning: A data-driven approach. Int. J. Appl. Earth Observ. Geoinf. 43, 119-131, doi: 10.1016/j.jag.2015.05.009.
- Reichstein, M., Bahn. M., Mahecha, M.D., Kattge, J. & Baldocchi, D. D. (2014) Linking plant and ecosystem functional biogeography. PNAS, 111, 13697-13702, doi:10.1073/pnas.1216065111.
- Mahecha, M.D. and Schmidtlein, S. (2008) Revealing biogeographical patterns by nonlinear ordinations and derived anisotropic spatial filters. Global Ecology and Biogeography, 17, 284–296, doi:10.1111/j.1466-8238.2007.00368.x.
From observations to models
- Sippel, S., Otto, F. E. L., Forkel, M., Allen, M. R., Guillod, B. P., Heimann, M., Reichstein, M., Seneviratne, S. I., Thonicke, K. & Mahecha, M.D. (2016) A novel bias correction methodology for climate impact simulations. Earth System Dynamics, 7, 71-88, doi:10.5194/esd-7-71-2016.
- Ilie, I., Dittrich, P., Carvalhais, N., Jung, M., Heinemeyer, A., Migliavacca, M., Morison, J.I.L., Sippel, S., Subke, J.-A., Wilkinson, M. & Mahecha, M.D. Reverse engineering model structures for soil and ecosystem respiration: the potential of gene expression programming. Geoscientific Model Development - Discussions, doi:10.5194/gmd-2016-242.
- Mahecha, M.D., Reichstein, M., Carvalhais, N., Lasslop, G., Lange, H., Seneviratne, S.I., Vargas, R., Ammann, C., Arain, M.A., Cescatti, A., Janssens, I.A., Migliavacca, M., Montagnani, L. & Richardson, A.D. (2010) Global Convergence in the Temperature Sensitivity of Respiration at Ecosystem Level. Science, 329, 838-840, doi:10.1126/science.1189587.
- Mahecha, M.D.,Reichstein, M., Jung, M., Seneviratne, S.I., Zaehle, S.,, Beer, C., Braakhekke, M.C., Carvalhais, N., Lange, H., Le Maire, G. and Moors, E. (2010) Comparing observations and process-based simulations of biosphere-atmosphere exchanges on multiple time scales. Journal of Geophysical Research-Biogeosciences, 115, G02003, doi:10.1029/2009JG001016.
Data analytic methods
- Sippel, S., Lange, H., Mahecha, M.D., Hauhs, M., Bodesheim, P., Kaminski, T., Gans, F. & Rosso, O.A. Diagnosing the Dynamics of Observed and Simulated Ecosystem Gross Primary Productivity with Time Causal Information Theory Quantifiers. PLoS ONE 11, e0164960, doi:10.1371/journal.pone.0164960.
- von Buttlar, J., Zscheischler, J. & Mahecha, M.D. (2014) An extended approach for spatiotemporal gapfilling: dealing with large and systematic gaps in geoscientific datasets. Nonlinear Processes in Geophysics, 21, 203-215, doi:10.5194/npg-21-203-2014.
- van der Maaten, L.J.P., Schmidtlein, S. & Mahecha, M.D. (2012) Analyzing Floristic Inventories with Multiple Maps. Ecological Informatics, 9, 1–10. doi:10.1016/j.ecoinf.2012.01.005.
- Zscheischler, J., Mahecha, M.D. & Harmeling, S. (2012) Climate classifications: the value of unsupervised clustering. Procedia Computer Science, 9, 897-906, doi:10.1016/j.procs.2012.04.096.
- Mahecha, M.D., Fürst, L., Gobron, N. & Lange, H. (2010) Identifying multiple spatiotemporal patterns: A refined view on terrestrial photosynthetic activity. Pattern Recognition Letters, 31, 2309-2317. doi:10.1016/j.patrec.2010.06.021.
Missing: Iulia, Rocio, Guido