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Updated: Jun 28, 2026
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Monitoring Pedogenic Inorganic Carbon Accumulation Due to Weathering of Amended Silicate Minerals in Agricultural Soils.
Published on: June 4, 2021
A framework for predicting global silicate weathering and CO2 drawdown rates over geologic time-scales
George E Hilley1, Stephen Porder
1Department of Geological and Environmental Sciences, Stanford University, Stanford, CA 94062, USA. hilley@stanford.edu
Summary
Global silicate weathering, crucial for atmospheric carbon dioxide (CO2) regulation, is primarily controlled by erosion rates, especially in mountain belts. This process consumes significant amounts of CO2, influencing long-term climate stability.
Area of Science:
- Geochemistry
- Climate Science
- Geology
Background:
- Silicate weathering is a key long-term regulator of atmospheric CO2.
- Factors influencing global silicate weathering rates, including tectonics, climate, and rock type, are not fully understood.
- Quantifying global silicate weathering is essential for climate modeling.
Purpose of the Study:
- To investigate the combined influence of erosion rates, dust fluxes, temperature, and water balance on global silicate weathering.
- To estimate global silicate weathering rates and their contribution to atmospheric CO2 drawdown.
- To identify the primary geographic regions and erosion rate ranges controlling global silicate weathering.
Main Methods:
- Development of a spatially explicit model for silicate weathering.
- Integration of global erosion rate data, General Circulation Model (GCM)-derived dust fluxes, temperature, and water balance.
- Comparison of model predictions with riverine silica flux measurements.
Main Results:
- The model predicts global silicate weathering of 1.9-4.6 x 10^13 mols of Si per year.
- Eighty percent of global silicate weathering occurs within an erosion rate range of 0.01-0.5 mm/year.
- Silicate weathering consumes 1.5-3.3 x 10^8 tons/year of CO2, with 50% occurring in mountain belts.
Conclusions:
- Local erosion rates are a primary control on global silicate weathering.
- Active mountain belts play a disproportionately large role in regulating global climate through silicate weathering.
- Tectonic activity is a critical factor in long-term climate regulation via silicate weathering.
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