PLEA Network

12 March 2019, The Conversation, Can we tweak marine chemistry to help stave off climate change? The world’s nations are nowhere near to meeting the global Paris Agreement’s goals on climate change of holding global temperature increases to 2 degrees Celsius compared to 19th-century averages, much less its more aspirational goal of holding temperatures to a 1.5°C rise. The most recent Emissions Gap Report from the United Nations Environment Program notes “global greenhouse gas emissions show no signs of peaking.” According to another study, the chance that humans can limit warming to no more than 2°C by 2100 is no more than 5 percent, and it’s likely that temperatures will rise somewhere between 2.6°-3.7°C by the end of the century. These foreboding trends have led to an increasing focus on ways to remove carbon dioxide from the atmosphere. Among the methods being explored is the use of the ocean to absorb and/or store carbon by adding crushed rocks or other sources of alkalinity to react with CO2 in seawater, ultimately consuming atmospheric CO2. Could this type of large-scale carbon dioxide removal work? A closer look illustrates the potential environmental trade-offs of deploying marine carbon dioxide removal and the complex technical, economic and international governance issues it raises. Read more here