Mapping where carbon needs to remain in its natural place to avoid climate catastrophe

by Bob Yirka , Phys.org

Fig. 1: Irrecoverable carbon in Earth’s ecosystems. a–d, Inlays show areas of high 

irrecoverable carbon density in the Pacific Northwest of North America (a), western South

 America (b), the Congo Basin (c) and the island of Borneo (d). Areas with zero

 irrecoverable carbon are displayed in gray to demonstrate the footprint of global 

manageable carbon. Credit: DOI: 10.1038/s41893-021-00803-6

An international team of researchers has created a map that highlights parts of the world that hold very high concentrations of carbon. In their paper published in the journal Nature Sustainability, the group describes their map and how it was created, noting that if the carbon in such areas is released, it would likely set off a climatic catastrophe. Peter Thornton with Oak Ridge National Laboratory has published a News & Views piece in the same journal issue, outlining the work done by the team in this new effort.

Scientists have known for many years that there are certain areas of the world that hold a tremendous amount of carbon—permafrost in the North, for example, or redwood trees along the northwest coast of the United States. In this new effort, the researchers have sought to highlight the important role these regions play in efforts by humanity to reduce carbon emissions.

The researchers note that other highly concentrated areas include the Amazon basin, the Congo Basin and parts of Borneo. Some are home to mangroves, others to peatlands. They describe these natural carbon sinks as 'irrecoverable' resources because if the carbon is released from them by human activities, it could take centuries for the areas to recover.

To learn more about the location of the planet's irrecoverable resources, the team studied satellite images and prior estimates of how much carbon is sequestered in these sinks. They then created a map of the world highlighting in purple hues these carbon sinks. In looking at the map, it is easy to see where they are—what is not so easy is developing a plan that protects such areas from encroachment. One striking feature of the map is how small irrecoverable resource areas are. They occupy just over 3 percent of Earth's total land area.

The researchers conclude that allowing all of the carbon in all of the world's natural sinks to be released would likely lead to catastrophe—139 gigatons of carbon would be dumped into the atmosphere, likely pushing the temperature of the planet far beyond the universal goal of 1.5 degrees C, with all of its associated climatic consequences.Brazilian forests found to be transitioning from carbon sinks to carbon sources

More information: Monica L. Noon et al, Mapping the irrecoverable carbon in Earth's ecosystems, Nature Sustainability (2021). DOI: 10.1038/s41893-021-00803-6

Peter Thornton, Mapping classes of carbon, Nature Sustainability (2021). DOI: 10.1038/s41893-021-00783-7

Journal information: Nature Sustainability 

© 2021 Science X Network