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Carbon Assimilation and Modelling of the European Land Surfaces |
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Second CAMELS consortium Meeting held at Lisbon, Portugal on 19th March 2003. Present: Met Office: Peter Cox LSCE: Pierre Friedlingstein, Philippe Peylin, Andrew Friend, Roger Dargaville, Diego Santeren MPI-BGC: Wolfgang Knorr, Jens Kattge, Manuel Gloor, Christian Rodenbeck ALTERRA: Isabel van der Wyngaert, Mart-Jan Schelhaas UNITUS: Dario Papale, Michele Meroni EFI: Ari Pussinen, Sergey Zudin CEH: Chris Huntingford JRC: Nadine Gobron, Bernard Pinty EC: Claus Bruning MPI-MET: Marko Scholze Apologies: Richard Betts, Venkata Jogireedy (Met Office), Riccardo Valentini (UNITUS), Philippe Ciais (LSCE), Richard Harding (CEH), Martin Heimann (MPI-BGC), Ronald Hutjes (ALTERRA), Thomas Kaminski (FastOpt), Michel Verstraete (JRC). Date of next meeting: The Netherlands, Oct or Nov 2003 (see action 2(d)) 1. Actions from previous meeting (29/1/03): a) PF to find out more about the Hyde land-use database and its relationship to what is planned in C4MIP. ACTION COMPLETED PF presented the methodology which has been adopted by Richard Betts (RB) to derive historical land-cover datasets for use within C4MIP. This involves combining two datasets: Ramankutty and Foley (1999), fraction of cropland on a 0.5o grid, annually for 1700-1990 Hyde dataset (Goldewijk, 2000), pasture and cropland (ON/OFF) on a 0.5o grid, every 50 years. RBs algorithm has been used to derive annual fractions of pasture and crop from 1700 to 1990. ACTION 2(a): RB to extend his methodology to year 2000 using remotely-sensed land-cover. b) NG to circulate questions concerning requirements for remote-sensing products (see item 2f) ACTION COMPLETED c) ALL to respond to JRC questions concerning requirements for remote-sensing products (see item 2f). ACTION COMPLETED Responses were not given, but the relevant decisions regarding the required remote-sensing products were made under item 2f of the agenda. d) WK, PF, G-JN to agree on distribution of inventory work between WP2 and WP3 (see item 4) ACTION COMPLETED AP sent around a document describing the role of EFI which was accepted. EFI split between WP2 and WP3 is therefore as in the Description of Work. e) JK to send round revised questionnaire including questions on requirements with respect to uncertainty estimates on flux data ACTION COMPLETED f) ALL MODELLING GROUPS to reply to questionnaire on data requirements (see item 2e) ACTION COMPLETED Late input on MOSES needs to be included. g) RoH to suggest appropriate flux sites for WP2 (see item 3) ACTION SUPERCEDED It was decided to adopt the 31 sites used for validation of ORCHIDEE as a first step (see item 2b) h) PMC to decide on appropriate host for website and ensure this is set up. ACTION ONGOING A webserver is now being set up at the Met Office to host the CAMELS website. The intention is to purchase an appropriate web address (most likely camels.org.uk since camels.org is already taken by a betting/loan company!) i) ALL presenters to send their presentations to PMC for inclusion on the website. ACTION ONGOING Only ALTERRA provided their presentation from the 1st meeting, so this action is ongoing and applies to both the 1st and the 2nd meetings. 2. Description of Land-surface models to be used in WP2, and associated data requirements. a) BETHY (MPI-BGC) WK described BETHY. Data requirements include leaf growth and decay (for a new and revised phenology scheme). BETHY runs offline using maps of temperature, rainfall, solar radiation (from ISLSCP) and estimates of leaf nitrogen content. The vegetation parameters are estimated from the literature, and with error bars. Such parameters include a growth respiration constant, leaf onset and leaf shedding temperatures, LAI of closed canopy, rooting depth. It was noted that model form and parameterizations of soil water limitation behaviour is highly dependent upon the computation of soil moisture content. There was some discussion of the urgent need to define a priori estimates of uncertainties in internal model parameters, based on existing literature. ACTION 2(b): ALL MODELLING GROUPS to provide estimates of uncertainties, plus relevant citable literature, for their own internal parameters. ACTION 2(c): AF to provide references to literature searches completed for BIOME-BGC and ECOCRAFT. ACTION 2(d): PF to arrange meeting of WP2 modelling groups, in Paris in late-April to discuss parameter uncertainties. b) ORCHIDEE (LSCE) PF described ORCHIDEE, which consists of a new land-surface scheme (STOMATE) coupled to the LPJ vegetation dynamics module. It is possible to run with vegetation structural change (i.e. change in LAI and canopy height), even if the vegetation dynamics is switched-off. ORCHIDEE validates impressively against data from 31 sites, even in the absence of calibration. As with other land-surface models there is a tendency to fit latent heat fluxes more closely than sensible fluxes. There was some discussion about the relative accuracy of H and LE eddy covariance measurements, but this was inconclusive. Further guidance is required from those running flux sites (see item 3a). c) MOSES2/TRIFFID (Met Office) PC described the MOSES 2 land-surface scheme and the TRIFFID dynamic vegetation model. MOSES 2 calculates the surface heat, water and CO2 fluxes on each atmospheric model timestep (typically 30 minutes), for each of up to 9 surface types (including 5 PFTs) in each gridbox. Carbon fluxes and leaf turnover rates are aggregated before being passed to TRIFFID, which updates the fraction of each PFT based on Lotka-type competition equations. Changes in vegetation structure and type are therefore intricately-linked. There was some discussion of whether vegetation dynamics need to be included in the historical simulations of WP3. PC felt that age-class distributions need to be treated to deal with the impacts of historical land-use change on the carbon budget. d) Forest Inventory Model (EFI) This was dealt with under agenda item 4. e) Summary of responses to questionnaire on models (Jen Kattge, MPI-BGC) JK presented the results of his questionnaire on the data requirements for the land-surface models to be used in WP2. It was noted that these seemed to be similar and therefore compatible. PC pointed out that his inputs on MOSES data requirements had not made it into the table presented (probably because they were provided so late!). There was still a need for estimates of measurement error for WP2, which requires input from those running flux sites (see agenda item 4a). f) Summary of responses to questionnaire on requirements for data from remote sensing (Nadine Gabron, JRC) NG described the questionnaire and the remote-sensing data which is potentially available. Although, no responses to the questionnaire had been received, the following requirements were specified after some discussion: Global, monthly FAPAR at 10km resolution (plus latitude-longitude equivalent) for the longest period possible (Sep 1997-Dec 2001). Site, 10 day FAPAR for the 31 flux sites to be used in the WP2 model experiments. ACTION 2(e): JRC to produce global, monthly FAPAR at 10km resolution, plus a latitude-longitude equivalent. ACTION 2(f): JRC to circulate CarboEurope flux sites for which FAPAR is already available. 3. Selection of appropriate measurement sites to be used in WP2 a) Description of possible sites (ALTERRA) It is was decided to use the 31 sites already prepared for validation of ORCHIDEE. Discussion focussed on ancilliary data requirements and estimates of measurement errors. It was decided that initial WP2 modelling should focus on the most completely measured sites, including estimates of LAI, soil temperature and soil moisture where possible. ACTION 2(g): PC to approach the LSCE guardian of the processed flux data, and ask for permission to use this within CAMELS ACTION 2(h): PF to circulate a description of the 31 sites ACTION 2(i): ALTERRA to assess the availability of ground-based LAI for the 31 sites. In order to provoke estimates of measurement errors from those running flux sites it was decided to produce rough estimates from within CAMELS and then send these to the coordinators of each site for correction ACTION 2(j): JK to circulate the questionnaire on measurement errors to the CAMELS data experts (ALTERRA, CEH, UNITUS), and collate the responses. ACTION 2(k): ALTERRA to send the estimated errors to flux site coordinators for comment! b) Site recommendations based on experiences with ORCHIDEE (Diego Santaren, LSCE) DS described his experiences with calibration of ORCHIDEE. Since the model did a good job at most sites even using its default parameters, it was quite difficult to make further improvements. However, the tuning algorithm was demonstrated to be taking the model in the right direction (i.e. towards a better fit to the data) c) Site recommendations based on experiences with MOSES (CEH). This item was cancelled due to time constraints. 4. Discussion on the role of Forest Inventory work within CAMELS (to be led by EFI). The note circulated on the EFI role in CAMELS was agreed to. AP described the EFI role in CAMELS and the CarboInvent FP5 project. It was hoped that there would be significant symbiosis between these efforts. The key first task for EFI in CAMELS is to locate and distribute information on historical disturbance for as many of the 31 flux sites as possible; ACTION 2(l): EFI to distribute information on subsets of the 31 flux sites where age-classes and/or historical disturbances are known. 5. Summary of actions (PMC) See separate document 6. AOB PC explained that CAMELS was being presented as a key part of the Integration component of the CarboEurope Integrated Project to be submitted to FP6. 7. Date and location of next meeting April 2003, Paris, WP2 discussion of uncertainties in internal model parameters (see action 2(d)). October or November 2003, The Netherlands Consortium meeting. ACTION 2(m): ALTERRA to arrange next consortium meeting in The Netherlands, October or November 2003. |
