18 May 2017
Planting trees cannot replace cutting carbon dioxide emissions, study shows
Posted by Lauren Lipuma
By Jonas Viering
Growing plants and then storing the carbon dioxide they have taken up from the atmosphere is not a viable option to counteract unmitigated emissions from fossil fuel burning, a new study shows.
Plantations would need to be so large they would eliminate most natural ecosystems or reduce food production if implemented as a late-regret option in the case of substantial failure to reduce emissions, finds the new study in Earth’s Future, a journal of the American Geophysical Union.
However, growing biomass soon in well-selected places with increased irrigation or fertilization could support climate policies of rapid and strong emissions cuts to stabilize Earth’s climate below 2 degrees Celsius, according to the study’s authors.
“If we continue burning coal and oil the way we do today and regret our inaction later, the amounts of greenhouse gas we would need to take out of the atmosphere in order to stabilize the climate would be too huge to manage,” said Lena Boysen, a researcher at the Potsdam Institute for Climate Impact Research (PIK) in Potsdam, Germany, and lead author of the new study.
“Even if we were able to use productive plants such as poplar trees or switchgrass and store 50 percent of the carbon contained in their biomass, in the business-as-usual scenario of continued, unconstrained fossil fuel use, the sheer size of the plantations for staying at or below 2 degrees Celsius of warming would cause devastating environmental consequences,” Boysen said.
In the new study, Boysen and her colleagues investigated the feasibility of biomass plantations and carbon dioxide removal using global dynamic vegetation computer simulations. Based on their results, they calculate that the hypothetical plantations would in fact replace natural ecosystems around the world almost completely.
If carbon dioxide emissions reductions are moderately reduced in line with current national pledges under the Paris Climate Agreement, biomass plantations would still have to be enormous, according to the study. In this scenario, plantations would replace natural ecosystems on fertile land larger than one-third of Earth’s existing forests. Alternatively, more than a quarter of land used for agriculture at present would have to be converted into biomass plantations, putting global food security at risk, according to the authors.
Only ambitious emissions reductions and advancements in land management techniques between mid-century and 2100 could possibly avoid fierce competition for land. But even in this scenario, only high inputs of water, fertilizers and a globally applied high-tech carbon-storage-machinery could likely limit warming to around 2 degrees Celsius by 2100, according to the study. To this end, technologies minimizing carbon emissions from cultivation, harvest, transport and conversion of biomass and, especially, long-term Carbon Capture and Storage (CCS) would need to improve worldwide, the authors said.
So far, biomass plantations as a means for carbon dioxide removal have often been considered as a comparatively safe, affordable and effective approach. “Our work shows that carbon removal via the biosphere cannot be used as a late-regret option to tackle climate change,” said Tim Lenton, a researcher at the University of Exeter, United Kingdom and co-author of the new study. “Instead we have to act now, using all possible measures instead of waiting for first-best solutions. Reducing fossil fuel use is a precondition for stabilizing the climate, but we also need to make use of a range of options from reforestation on degraded land to low-till agriculture and from efficient irrigation systems to limiting food waste.”
“In the climate drama currently unfolding on that big stage we call Earth, carbon dioxide removal is not the hero who finally saves the day after everything else has failed,” said Hans Joachim Schellnhuber, Director of PIK and co-author of the new study. “It is rather a supporting actor that has to come into play right from the beginning, while the major part is up to the mitigation protagonist. So this is a positive message: We know what to do – rapidly ending fossil fuel use complemented by a great variety of CO2 removal techniques. We know when to do it – now. And if we do it, we find it is still possible to avoid the bulk of climate risks by limiting temperature rise to below 2 degrees Celsius.”
— Jonas Viering is in the public relations department at PIK. This post originally appeared as a press release on the PIK website.
Please send me updates.. to declare, to continuously do war on climate change ..
Please send me updates.send this details in mail to all the public policy makers, religious heads, universities, heads of government’s, environmentalists, organisations concerned on environment education, activists to save the lonely planet mother earth.
Excellent alert! Thank you. Not many of us are saying planting trees is all we need to do. Of course, more shades and animal habitat could be critical, so putting a stop to cutting trees down would be a nice start. Chemical pollution, over population, and ecosystem destruction are other issues we must deal with, and many other strategies will be required, some of which you mentioned. We need to make all new houses, buildings and transportation carbon-free energy generators and abandon fossil fuels; restrict overall natural resource consumption and land development; reduce, reuse, recycle, and clean up all plastic and wood products; phase in non-toxic/chemical homes and farms; adopt and enforce green sustainable policies locally and nationally throughout the economy, including schools, military, government offices, and industry; and harness new sustainable technologies for decarbonization, water purification and so forth. Meanwhile, prepare for the worst and cooperate for the best.
Animal Agriculture is the leading industry for Climate Change. When we eat, wear and use animal products we create, encourage, allow and promote deforestation, hunger, wildlife extinction, diseases and violence. The BEST, most natural, intelligent WAY to prevent all of the above is to choose a plant-based/vegan lifestyle. There’s nothing else, no matter how hard we try… wouldn’t be enough. 80% of the farmed lads are used to feed lad animals instead feeding people. 50% of water resources are given to farmed animals. The manure coming from farmed animal is 120times more than people. Animal Agriculture could NEVER be natural, sustainable, necessary or logical. It’s self- destructive and deadly. When we eat animal products (flesh, dairy, eggs) we create deadly diseases such as Alzheimer’s, diabetes,Osteoporosis, impotence, hard attack’s, and cancer. The violence towards other species the most unimaginable horror each and every time. Racism, discrimination, violence begins on our plate. When are vegan, we respect, admire, protect and defend Mother Nature.
Yes of course. We need to balance the carbon cycle again – reduce burning (and spilling) of oil AND grow the biosphere, particularly soil, marshlands, and forests.
Everybody has a pet favourite, so we can easily use them all in the this rescue. It’s certainly start to plant then fix other stuff along the way like quitting beef eating & reversing land use back to forest etc. And it’s a no brainer to accelerate the transition from fossil fuels to renewables.