18th Swiss Global Change Day - Meeting Report and Conference Documents
On 11 April 2017, the Swiss global change science community met for the 18th time on the annual Swiss Global Change Day. About 220 participants attended the event and 70 posters were exhibited. Distinguished researchers presented scientific highlights and the program provided enough time for discussions and networking. This went hand in hand with the key messages: Be a connector and a communicator. Also, ProClim followed that principles: For the first time there was a live reporting about the event on the Twitter channel of ProClim.
Erich Fischer from the ETH Zurich gave a talk about «Global weirding or insignificant change – Extremes in a changing climate» – a title that can be interpreted in different ways: First Erich Fischer pointed out that both «extreme» views – frightening people about climate change as well as declaring changes in climate as insignificant – can backfire (statements wouldn’t be taken seriously anymore) and that it’s important to differentiate.
According to Fischer, the awareness for climate change depends on the event type and the spatial and temporal scale. However, Fischer showed us with several examples that changes in heavy rainfall and temperature extremes are detected at global scale which makes this change not insignificant.
Fischer also summed up the challenges in modelling climate change: Changes are complex but likely not inexistent, observational evidence is affected by high variability, many model runs are required to isolate a signal and the link between «meandering» (the atmosphere does not behave like a meandering river) and extremes is not straight-forward.
He pointed out that, on one hand, changes in atmospheric dynamics remain the big unknown for extremes. Event types where atmospheric dynamics are dominant are droughts, wildfires, tropical and extratropical cyclones, severe convective storms and events concerning snow and ice. On the other hand, thermodynamic effects alone have already substantially increased probabilities of temperature and heavy rainfall events. The more dominant the thermodynamic contribution is – the higher our confidence for an attribution to anthropogenic influence.
Markus Reichstein from the Max-Planck Institute for Biogeochemistry in Jena showed in his presentation the climate extreme effects on biogeochemical cycles. It is very likely that climate extremes contribute to a positive carbon cycle feedback. In this context, the carbon-water cycle interactions are crucial. During the European heatwave and drought in 2003 for example the terrestrial system turned to be a C-source due to high respiration and reduced C-uptake. In his work, Reichstein shows that C-cycle extremes often are associated with drought.
In the second part of his presentation Reichstein talked about ongoing research, open questions and even beyond: What about the significance of multivariate and compound extremes? The system response can be equivocal and unintuitive. An event-based data-driven approach to link physical, biological and societal sub-systems seems to be important to better understand the effects of extreme events and system interactions in the future.
What brings people in developing countries to construct and use latrines? And how can we motivate people in Ethiopia to perform more hand washing at key times? Hans-Joachim Mosler from the Environmental Social Sciences department at EAWAG raised in his presentation many of those questions and thereby tackled the issue of how to introduce behavior change in developing countries in order to overcome health and environmental problems. His answer: we need to understand how behavior change works. A simple promotion of a new behavior does not necessarily lead to behavior change, thus researchers have to find out what is going on in people’s heads. Not only rational considerations are influencing behavior and habits. Rather risk, attitude, norm, ability and self-regulation factors are the complex psychosocial factors for behavior change.
In the RANAS systematic behavior change approach, which he applied in many studies in developing countries, these factors are identified with qualitative interviews first, then measured and analysed. According to the results behavior change techniques and strategies are selected, implemented and later monitored regularly. How this works in the field he illustrated with many examples, for instance an introduced community water filter in Ethiopia, where they were able to increase consumption of safe water and moreover change the perceived costs without changing real prices. He is convinced; evidence-based behavior change techniques are a powerful tool and more effective than interventions based on common sense approach.
Anabela Carvalho from the Department of Communication Sciences at the University of Minho in Portugal illuminated the contributions of communication and critical social research to a better understanding of the collective (in)action on climate change.
Initially Carvalho presented the ingredients for a transformation: changes in social structures and relations, including addressing the growing economic and political power of elites and both individual agency and collective action by societies. Collective action in turn bases on the consciousness of human agents whose activities must change and a «we» together with a «constitutive outside» to carry out the change.
In the second part of her talk Carvalho explained several of the discursive processes that hamper the development of citizens «consciousness of the possibility of change» and the constitution of a «we», such as universalization of responsibility, naturalization of (anthropogenic) climate change or the hegemony of sustainable development discourses, all contributing to climate change’s post-political condition. This de-politicization of climate politics and climate communication impedes a democratic debate. There is no confrontation between «real» alternatives towards sustainable futures anymore and structural and historical causes get obscured precluding critical inquiry. All these factors shrink the space for citizen engagement. But climate change causes radical changes in societies and therefor requires plural debates.
Is it possible to find re-politicizing discourses, to reinvent the political engagement with processes of debate? Carvalho affirmed and pointed out that one has to work with progressive social groups like the climate justice movement, connective action or with citizen in general.
Karin Ingold from the Institute of Political Science at the University of Bern and the and Social Science Department at EAWAG talked about the acceptance of new policy measures in the field of climate adaptation and mitigation. To begin with, she pointed out the general characteristics of environmental problems (complex and with many uncertainties) and that this challenges the political system. In Switzerland, with its federalism and direct democracy, a lot of actors from different levels and citizens participate in the political process and have to be persuaded for a certain strategy. The basic assumption is that as soon as local entities such as cantons, municipalities and individuals accept a strategy it becomes easier to implement new policy instruments.
In the following, Ingold presented two studies in the field of flood prevention. The overall-result indicated that it is difficult to introduce new and cross-sectoral policies. Another finding was that the problem perception and the affectedness of actors influence the acceptance and the choice of new policy measures. Municipalities for example tend to choose information as an instrument, whereas scientists are in favour of spatial planning. Another study in the field of climate mitigation showed that also the perception and affectedness at the citizen level matters in regard to the acceptance of new instruments; this is especially true for prosumers, left-wing supporters and advocates for climate change mitigation. In her conclusion Ingold states that no general acceptance trend for more coercive policy instruments can be identified and that actors are reluctant to new or cross-sectoral policy instruments.
Tim Lenton from the University of Exeter/UK dealt in his talk with the current knowledge on tipping points in the climate system, possible consequences on climate policy and early warning potential. In the climate system, there are in general three processes that might involve tipping points: melting, circulation changes (atmosphere and ocean) and biome changes. Current knowledge on the probability of passing tipping points is still limited. An expert evaluation based on three different warming scenarios and five possible tipping points (Atlantic overturning circulation; melting of Greenland ice sheet; melting of Antarctic ice sheets, dieback of Amazonian forest, changes in El Niño pattern) produced a 16 % chance for passing at least one of the five tipping points for a 2-4 °C global warming and a corresponding 56 % chance for a > 4°C global warming.
Concerning the possibilities of early warning, model calculations suggest that when a system approaches a tipping point, recovery from perturbations of the system gets lower – which produces prolonged disturbances – and the system slows down – which means a decrease of variability.
In view of mitigation or climate policy, the inclusion of possible tipping points influences cost-benefit analyses. Adding potential tipping points to a cost-benefit model (with an increase of the probability of passing tipping points with increasing warming) produces lower discount rates and higher costs for carbon emissions. Lenton concluded that the threat of multiple, interacting, uncertain climate tipping points should be triggering stronger mitigation activity now to reduce their likelihood. The optimal policy response from a standard cost-benefit model with a realistic specification of risk aversion is a carbon price today of > $100/tCO2.
At the end of the event Thomas Stocker from the University of Bern advised the science community to be a connector between the three areas global change research is made (natural, biological and human sciences) and to be a communicator for the important topic of global and climate change and that communicating requires emotions – along with facts.
About 70 posters were presented at the 18th Swiss Global Change Day in the categories Atmosphere/Hydrosphere, Geosphere/Biosphere, Human Dimensions/Sustainability. In the poster session the best posters in the different fields were selected by a jury and honoured with a travel award of 1000 CHF each.
The following posters were awarded:
Leonie Bernet (University of Bern): Cloud Effect on Temperature Profiles from Microwave Radiometry
Regula Mülchi (University of Bern): Human Influence on the Runoff Regime and Runoff Extremes of the River Thur?
Maria Vorkauf (University of Basel): The influence of snow cover duration on alpine plant phenology
Marta Marchegiano (University of Geneva): The climate history of Lake Trasimeno (central Italy) during Late Glacial-Holocene transition revealed from ostracod assemblages (special awarded for a creative presentation)
Guillaume Rohat (University of Geneva): Assessment of Future Social Vulnerability to Climate Change in Sub-Saharan Africa