Seite - 18 - in options, Band summer 2017

www.iiasa.ac.atoptions ◼ summer 201718 I magine pumping air into a party balloon. As it fills, you can press your fingers against any weak spots to alleviate the strain. The balloon swells and you save the weak spots from catastrophic failure– but of course, you have simply shifted the pressure somewhere else. “All of our various demands on the land system, from mining to agriculture and forestry, are like pumping air into that balloon,” says IIASA researcher Brian Walsh. “Conservation,” he adds, “is like putting your finger over the weak spot–it can put pressure on the system elsewhere.” IIASA has been working on these trade- offs for some time, constructing models to see how our interconnected planet copes with various challenges (see box). One such model, the Global Biosphere Management Model (GLOBIOM) examines the tension between safeguarding the environment and producing vastly more food than we do now. Go vegetarian Walsh and his colleagues are searching for the interventions that minimize the trade-offs and, hopefully, create synergies too. Surprisingly, one intervention has emerged that is “an order of magnitude more positive than any other intervention in conservation,” says Walsh. This measure led to a reduction in deforestation, irrigation, fertilizer use, and biodiversity loss— as well as greenhouse gas emissions. This intervention was giving up meat. Meat consumption is predicted to rise by 50% by 2050. In a recent study, the researchers held consumption constant instead–reflecting a reduction in meat consumption in the developed world and an increase in poorer countries to satisfy nutritional goals. “All of this land that the model thinks will be needed for pasture and animal feed is freed and so there’s less deforestation, less irrigation, less fertilizer use, and less biodiversity loss–and fewer greenhouse gas emissions,” says Walsh Put another way, it’s like letting air out of the balloon, and Walsh is now convinced that eating less meat “is the single largest thing that anyone can do to care for the planet”. Coal or clean fuels? Another area that may cause clashes between conservation and development is the quest to bring modern energy to all by 2030–UN Sustainable Development Goal 7–which can seem in opposition to the Paris Agreement to keep global temperature rise at less than 2°C above pre-industrial levels. What happens when work towards one sustainability goal prevents progress in another? Do we have to choose between universal energy access and climate change mitigation, or biodiversity and food security? The balancing act of sustainability