Consider the following activities: 1. Spreading finely ground basalt rock on farmlands extensively 2. Increasing the alkalinity of oceans by adding lime 3. Capturing carbon dioxide released by various industries and pumping it into abandoned subterranean mines in the form of carbonated waters How many of the above activities are often considered and discussed for carbon capture and sequestration?

Stories on this topic

• India's first payments to farmers for soil carbon

  Tests carbon removal methods, including farmland-based sequestration, the idea behind paying for soil carbon.

• UNEP says 1.5°C will be crossed and maps an 'overshoot, peak and decline' path

  The overshoot pathway depends on carbon capture and removal; the report's split between conventional and novel removal helps you judge which listed activities count.

• Study finds rapid Himalayan erosion releases CO2 through pyrite oxidation

  Spreading basalt on farmland is enhanced weathering; this story explains the chemistry and why rock choice matters, since sulphide-bearing rock can release CO2.