Context:
Mati Carbon, Indian-led climate initiative that uses an Enhanced Rock Weathering model wins $50m XPRIZE Carbon Removal competition
Enhanced Rock Weathering (ERW) Model:
- A geoengineering technique that accelerates the natural weathering of rocks to capture and store atmospheric CO₂.
- Involves grinding basalt or other silicate rocks into fine powder and spreading it over landscapes like farmlands, forests, and coastlines.
- The powdered rock reacts with CO₂ in rainwater, forming stable carbonates and bicarbonates, which eventually wash into rivers and oceans, locking away carbon for thousands of years.
- ERW mimics the natural carbon cycle, but at an accelerated rate, making it a promising climate mitigation strategy.
Mechanism & Process:
- Rock Selection – Basalt and other volcanic rocks are chosen for their high calcium, magnesium, and iron content, which enhances CO₂ absorption.
- Grinding & Spreading – Rocks are finely ground to increase surface area, then spread over soil to boost chemical reactions.
- Chemical Reaction – Rainwater absorbs CO₂, forming carbonic acid, which reacts with minerals in the rock to create stable carbonates.
- Long-Term Storage – These carbonates wash into water bodies, preventing CO₂ from re-entering the atmosphere for over 10,000 years.
- Benefits – Carbon Sequestration, Soil Fertility Improvement, Reduced Fertilizer Dependency and Ocean Acidification Reduction
Source: IE
Previous Year Question
Consider the following statements:
1. Other than those made by humans, nanoparticles do not exist in nature.
2. Nanoparticles of some metallic oxides are used in the manufacture of some cosmetics.
3. Nanoparticles of same commercial products which enter the environment are unsafe for humans.
Which of the statements given above is/are correct?
[UPSC Civil Services Exam – 2014 Prelims]
(a) 1 only
(b) 3 only
(c) 1 and 2
(d) 2 and 3
Answer: (d)
Explanation:
Statement 1 is not correct:
A nanoparticle is a small particle that ranges between 1 to 100 nanometres in size. They could be generated by natural processes or could be made artificially and released into the environment.