(page 69 in Moving to Higher Ground, © John Englander, 2021)
As introduced in Chapter 4, “Reducing CO2 and Being Resilient are Not Enough” we have passed the point when reducing greenhouse gas emissions can return us to a stable climate, weather system, polar ice caps, sea level and coastlines. There is no plausible path to avoid the effects in the next few decades, even with the most aggressive proposals to slow the warming by switching to renewable energy.
With the level of carbon dioxide now approaching 420 ppm (parts per million) well above the range of 180 – 280 ppm for the last several million years, we now must look at ways to stave off the effects, even those that have been considered risky.
Often described as geo-engineering, these approaches generally are in two categories. One aims to reduce the level of carbon dioxide and other greenhouse gases in the atmosphere. The second aims to reduce the amount of solar energy received, the direct force of warming. Some examples are shown below in the two categories. No single concept will fully address the problem.
Carbon Dioxide Removal - Examples
- Massive tree planting
Ref: article The Global Tree Restoration Potential by Jean-Francois Bastin, et al. https://www.science.org/doi/10.1126/science.aax0848
- Direct air capture and removal of CO
Climeworks is an operating example in Iceland. https://climeworks.com/
- Ocean iron fertilization of phytoplankton or kelp permaculture to sequester organic carbon reducing carbon dioxide in the atmosphere
Ref: “A Research Strategy for Ocean-based Carbon Dioxide Removal and Sequestration” (2021) https://www.nap.edu/catalog/26278/a-research-strategy-for-ocean-based-carbon-dioxide-removal-and-sequestration
- Synthetic limestone as a building material
https://www.blueplanetsystems.com/products
Solar Radiation Management - Examples
- Marine cloud brightening, to reflect more sunlight
For an example see the Youtube of Stephen Salter with his concept for ships to use saltwater to make clouds more reflective. https://youtu.be/ktcWQ2vLoTI
- Injection of sulfur dioxide into the atmosphere to reflect sunlight
https://acp.copernicus.org/articles/16/2843/2016/
- Mirrors in space to deflect some of the incoming solar energy
https://en.wikipedia.org/wiki/Space_mirror_(climate_engineering)
Various institutions and specialized nonprofits are now focused on this new field of research and have websites with further information, e.g.
- Centre for Climate Repair at Cambridge https://www.climaterepair.cam.ac.uk/
- Foundation for Climate Restoration org/start-here/
- S. National Academy of Sciences http://www.nasonline.org/
As this field of scientific study and engineering experimentation are rapidly evolving, it is important that anyone interested do a search for the latest information, publications, meetings and policy discussion.