ALBERT

Description: Earth system models (ESMs) are currently the most advanced tools with which to study the interactions among humans, ecosystem productivity, and the climate. The inclusion of storm damage in ESMs has long been hampered by their big-leaf approach, which ignores the canopy structure information that is required for process-based wind-throw modelling. Recently the big-leaf assumptions in the large-scale land surface model ORCHIDEE-CAN were replaced by a three-dimensional description of the canopy structure. This opened the way to the integration of the processes from the small-scale wind damage risk model ForestGALES into ORCHIDEE-CAN. The integration of ForestGALES into ORCHIDEE-CAN required, however, developing numerically efficient solutions to deal with (1) landscape heterogeneity, i.e. account for newly established forest edges for the parameterization of gusts; (2) downscaling spatially and temporally aggregated wind fields to obtain more realistic wind speeds that would represents gusts; and (3) downscaling storm damage within the 2500 km2 pixels of ORCHIDEE-CAN. This new version of ORCHIDEE-CAN was parameterized over Sweden. Subsequently, the performance of the model was tested against data for historical storms in southern Sweden between 1951 and 2010 and south-western France in 2009. In years without big storms, here defined as a storm damaging less than 15  ×  106 m3 of wood in Sweden, the model error is 1.62  ×  106 m3, which is about 100 % of the observed damage. For years with big storms, such as Gudrun in 2005, the model error increased to 5.05  ×  106 m3, which is between 10 and 50 % of the observed damage. When the same model parameters were used over France, the model reproduced a decrease in leaf area index and an increase in albedo, in accordance with SPOT-VGT and MODIS records following the passing of Cyclone Klaus in 2009. The current version of ORCHIDEE-CAN (revision 4262) is therefore expected to have the capability to capture the dynamics of forest structure due to storm disturbance on both regional and global scales, although the empirical parameters calculating gustiness from the gridded wind fields and storm damage from critical wind speeds may benefit from regional fitting.

Description: Last December, Paris was the host city for the 21st Conference of the Parties (COP21) of the United Nations Framework Convention on Climate Change (UNFCCC). Representatives of 195 countries met to dispute a legally binding climate agreement – a highly complex process involving thousands of politicians, scientists and activists, that to date has taken over two decades. The director ensemble “Rimini Protokoll” re-enacted this mammoth-scale drama of diplomacy in the play “Weltklimakonferenz” (World Climate Conference) at the “Deutsches Schauspielhaus” theatre in Hamburg, Germany. Since the opening night (21st Nov. 2014), the play has been performed 16 times, reaching an audience of over 9000. All performers in the play were experts and scientists at different stages of their careers, including PhD students, journalists and professors. Each spectator took on the identity of a delegate of one of the 195 participating countries. We will present the project and the performance, thereby highlighting the role of and the interaction between the spectators and early career scientists. In a nutshell the play went as follows (https://vimeo.com/137817619); after an opening ceremony, the audience was divided up into seven groups, each of which was given advice by experts in several different briefings. These informed on country-specific challenges caused by the social and economic situation, possible future climatic changes and negotiating tactics. In addition, the delegations had bilateral meetings, enabling them to exchange views and experiences with one another. Towards the end of the play each delegation was asked to submit a national commitment to greenhouse gas reduction and a financial contribution to the Green Climate Fund. Based on these national commitments, the final plenum revealed whether or not the delegations had managed to submit reductions compatible with restricting global warming to 2°C compared to pre-industrial times. Due to their direct personal involvement in the play, each spectator was confronted with the full complexity and challenge of a climate change conference: Revealing the "culprit" - in other words the causes of climate change – is all about facts. In contrast, when developing options for action, the matter at hand is ultimately values. Which risks should the world community take on? What cost is it prepared to accept to protect the population in areas menaced by droughts or floods? These are all decisions based on political, economic, and indeed ethical issues. Based on feedback from spectators both during and after the performance, we will discuss to what extent the performance managed to convey the complexity of the question at hand and to what extent the spectators actually took on the role of their given country. The spectators were not the only ones to be put out of their comfort zone during the performance. Also the experts had to, in cooperation with the directors, think carefully on how to find the right balance between scientific integrity and a captivating dramaturgy, ultimately leading to a performance that would be informative, thought-provoking, as well as enjoyable.