Summary: SUMMARY: Bojana Bajzelj of Cambridge finds raising food for 9 billion will take all our carbon emissions. Benjamin Blonder tells us how the current plant world was shaped by the last big meteorite hit. Eelco Rohling: sea level rose 5 meters (16 ft) in the last big warming melt. Radio Ecoshock 141015 Welcome to Radio Ecoshock. I'm Alex Smith with a show crammed with science that matters. Three new papers on climate change: rising emissions from our food system, seas rising 5 meters, over 16 feet in a single century, and the big bang of a meteor strike. Let's go. Listen to or download this Radio Ecoshock show in CD Quality (56 MB) or Lo-Fi (14 MB) Or listen right now on Soundcloud. SOON FOOD PRODUCTION TAKES UP ALL OUR GREENHOUSE GAS EMISSIONS Several scientist guests on Radio Ecoshock warn we will never be free of carbon emissions because our food system creates greenhouse gases. It comes from clearing forests for fields, from stirring up the soil, from petrochemical-based fertilizers, from cows and other animals (as methane), and then whatever we use to transport the food to your home. How bad are those food-based emissions? Figures vary from 20% of our total emissions, all the way up to 50%. They are large enough, and growing so much, that in a few decades all the carbon we can possibly afford to release will come from our food system. That means all industry, transportation, and products must be carbon free - or we live in a dwindling damaged climate. A new study led by Cambridge University in the UK, assisted by Scottish scientists calculates the carbon future of agriculture. I reached the study's lead author, Dr. Bojana Bajzelj. Bojana is from the Department of Engineering at the University of Cambridge. The paper published at the end of August 2014 is titled "Importance of food-demand management for climate mitigation". That's in the journal Nature Climate Change, a closed journal, but you can get the abstract and some of the charts in this article. The more scientists look, the impacts of overpopulation are impossible. A new study from the University of Washington projects world population by the year 2100 will be 12 billion people, 3 billion higher than figures accepted by the United Nations. Even if it's 9 billion people, a study out of Cambridge University calculates the greenhouse gases just to feed that population will swallow the entire budget for greenhouse gases. Even at our current 7 billion plus people, we are cutting into rich biological forests like the Amazon and Congolese rainforests, to grow more food, especially for meat production. The Cambridge study predicts the world will lose yet another 10 percent of existing forests in the scramble to feed ourselves. Are you worried about losing half our wildlife in the last 40 years? Bojana tells us that agricultural deforestation is the Number One cause of loss of biodiversity. These scientists tell us that by 2050, emissions from the food system will be 80% higher than they were in 2009 (when they were already at a record high amount). I asked Bojana if their study also included a scenario where the world population went DOWN. That seems like a fair question in these days of Ebola. They did not consider this. She recommends the work of Dr. Hans Rosling on population predictions. Rosling offers many statistics on why we shouldn't panic on population. I disagree, but you can see his video "Don't Panic, the Truth About Population" here. When we burn or cut forests, we lose carbon to the atmosphere twice. The trees themselves are made of carbon. That is released to the air. But forests also buffer some of our carbon pollution, and we lose that too. ANOTHER POSITIVE FEEDBACK LOOP We encounter rapid human population growth as yet another positive feedback mechanism. Bajzelj covered that in another paper, released this summer with Keith S. Richards. The title is "The Positive Feedback Loop between the Impacts of Climate Change and Agricultural Expansion and Relocation"
