Improving representation of photosynthesis in Earth System Models

9th New Phytologist Workshop

April 2014, Montauk, New York


Rationale and scope


To provide realistic projection of our future climate, Earth System Models (ESMs) must accurately model global carbon fluxes. Terrestrial photosynthesis (A) is the largest of these fluxes, dwarfing anthropogenic CO2 emissions. The response of A to rising [CO2] and temperature is also one of the greatest sources of uncertainty in ESMs. Currently these models do not include existing process knowledge of acclimation to global change (rising CO2 concentration and temperature), and disagree strongly on the representation of drought impacts (De Kauwe et al. 2013). For instance, less than one third of the large-scale models surveyed by Smith and Dukes (2013) incorporated any type of acclimation to temperature, and only one model incorporated acclimation to both temperature and CO2. The timing of this workshop fits nicely in the cycle of IPCC Assessment Reports (AR), AR5 is slated for publication in 2014. In order for scientific products to impact AR6 (assuming publication in 2020) they need to be integrated into the models within the next 2–3 years. Therefore, this proposed workshop is perfectly timed to impact model development for AR6. This workshop also complements the 8th New Phytologist Workshop on Respiration (July 2013).

The workshop has two specific goals; (1) Identify areas of weakness in existing ESMs where current process knowledge and emerging data sets can be used to improve model skill, and identify a path forwards to implementing those changes, (2) Identify areas of weakness or gaps in current scientific understanding of photosynthesis that directly impact model output, and identify the research tasks necessary to close those gaps.

In order to address these goals it is essential that modellers and experimentalists work together. Experimentalists need to understand the limitations that the modellers face, and need a deeper understanding of how models assimilate process knowledge. Modellers need to understand the limitations of their assumptions and the physiological weaknesses in their parameterization and algorithms.


Organising committee


Alistair Rogers (Brookhaven National Laboratory)

Jeffrey Dukes (Purdue University)

Belinda Medlyn (Macquarie University)


Participation in the Workshop is by invitation-only.



For more information about this workshop please contact Michael Panagopulos ( in the New Phytologist Central Office.