How will we know if our model works?

Simply put, models are notorious for “getting it wrong” and equally well recognised as the only way we know how to “predict the future”. That said, our GPP model isn’t predicting the future, it’s a hind-cast model, re-analysing observations and quantifying primary production based on our thorough understanding of climates past.

Spanning recent decades, our hind-cast model will produce moderate resolution monthly epoques of GPP accumulation based on remotely sensed estimates of greenness and absorbed radiation and Bureau of Meteorology and CSIRO climatology’s of the land surface. We will calibrate and validate our model against the OzFlux network of towers- the only internationally recognised way to observe carbon fluxes for biomes.

Our model provides a baseline for comparison against other approaches to modelling GPP, i.e. state-of-the-art, high-temporal resolution models capable of resolving carbon fluxes at more frequent time steps and higher resolutions- in other words, the complex approach.

Our model is uniquely simple because it can be at 5km on monthly time scales. It’s usability comes from its malleable, simple design which can be modified or repeated with ease.

Our challenge: If you can’t do it better than a simple model- then why bother?

Our simple model and modelling system will be released into the public domain so that it can be benchmarked by the world.

This work is licensed under a Creative Commons Attribution 3.0 Unported License.

This project is supported by the Australian National Data Service (ANDS). ANDS is supported by the Australian Government through the National Collaborative Research Infrastructure Strategy Program and the Education Investment Fund (EIF) Super Science Initiative.

For more information visit the ANDS website ands.org.au and Research Data Australia services.ands.org.au.

Who uses modelled GPP?

Consumers of GPP products and systems designed to parameterise-your-own models are traditionally ecosystem scientists, ecohydrologists and ecosystem modellers. However, these data and systems are commanding a broader audience as scientific, economic, agronomic and political communities seek to better understand and model the carbon cycle. It follows that each of these diversely different communities has a variety of end-use applications. As such, we expect our GPP product to have a variety of end uses, including, but not limited too;

1.  Benchmarking systems for comparing ecosystem and ecohydrology models, for example, the International Land-Atmosphere Benchmarking Project (iLAMB).
2.  Demonstration and evaluation of a range of remote sensing data streams characterising the primary drivers, absorbed photosynthetically active radiation and climatology’s.
3.  Large-scale (i.e. continental and global) carbon balance and water resources assessment.
4. Development of CarbonTracker Australasia and contribution to other regional carbon modelling activities.
5. Information about primary production of natural and managed ecosystems.
6. Demonstration as high-profile application of Terrestrial Ecosystem Research Network data streams.

Common amongst all users is the need to assess spatially explicit changes in GPP over time. Specifically, this means ability to visualise and farm data from the time series imagery and process it further. Our strategy is to focus on addressing this common need robustly rather than developing a range of potentially limited use end-user functionalities.

This work is licensed under a Creative Commons Attribution 3.0 Unported License.

This project is supported by the Australian National Data Service (ANDS). ANDS is supported by the Australian Government through the National Collaborative Research Infrastructure Strategy Program and the Education Investment Fund (EIF) Super Science Initiative.

For more information visit the ANDS website ands.org.au and Research Data Australia services.ands.org.au.