MONTHLY NEWSLETTER OCTOBER 2018
Woods Hole Research Center How—and why—to limit warming to 1.5° Dr. Philip B. Duffy President & Executive Director
Earlier this month the Intergovernmental Panel on Climate Change released a special report, discussing the advantages of limiting global warming to 1.5°C (instead of 2°), and the challenges of meeting that stricter goal. The advantages are many: every known manifestation and societal impact of climate change is less in a 1.5° world than in a 2° world. These include extreme weather and its consequences, impacts on agriculture, human health, ecosystems, water scarcity, and so on.
Perhaps the most important difference between a 1.5° world and a 2° world is in the amount of sea level rise. More and more science suggests that sea level will be 5–10 meters higher in a 2° world than it is today. Even though this would probably take centuries to unfold, it is no light matter to condemn our descendants to the abandonment of coastal cities and low-lying island states. Limiting warming to only 1.5° might well result in substantially less ultimate sea level rise, although the science is still imprecise on this point.
In terms of what we’d need to do to limit warming to 1.5°, it’s daunting. The IPCC outlines four scenarios that meet the goal. Each uses a different mix of the four tools at our disposal: decarbonization of the energy system, energy efficiency, removal of CO2 from the atmosphere, and controls on non-CO2 greenhouse gases. I can’t resist pointing out that all of the scenarios involve substantial removal of CO2 from
the atmosphere through restoration of natural systems—a central focus of our work at WHRC. All require that humanity be “net neutral” by 2050–2060, meaning that at that point we’ll need to be removing as much CO2 from the atmosphere as we are adding.
The bottom line is that while it may be technically feasible to limit global warming to 1.5°, this would require a massive, multifront, global scale effort, undertaken immediately. The political will for this is not now detectable. This means that we all of us, especially those outside of government, need to do more. I am proud of the important contributions that WHRC is making: • Developing the science behind “natural climate solutions”— using natural pathways to remove CO2 from the atmosphere‚ and working with public and private sector partners to implement those solutions.
• Engaging decision makers at state, national and international levels to debunk the myth that burning wood to generate power is “carbon neutral.” To support this, LIMIT continued on next page
WHRC is an independent research institute where scientists investigate the causes and effects of climate change to identify and implement opportunities for conservation, restoration and economic development around the world. WHRC has been ranked as the top independent climate change think tank in the world for four years in a row. Learn more at www.whrc.org.