The Carbon Knowledge Base
Understanding carbon — from molecular bonds to global systems.
Knowledge as the antidote to corruption.
CO₂ + H₂O + light → C₆H₁₂O₆ + O₂
Tanso (炭素) is the Japanese word for carbon — element 6, the backbone of organic chemistry and the fulcrum of Earth's climate system. This wiki explores carbon in all its dimensions: the elegant molecular structures that make life possible, the biogeochemical cycles that regulate planetary temperature, and the human activities that have disrupted those cycles.
Carbon is not the villain. It is the most versatile element in the periodic table, forming more compounds than all other elements combined. The challenge is not carbon itself but the rate at which we have relocated it from geological storage into the atmosphere.
612.011 u~428 ppmThe biological carbon cycle moves ~120 GtC/year between atmosphere, oceans, and terrestrial biosphere. Photosynthesis draws CO₂ from the air; respiration and decomposition return it. Ocean surface waters exchange CO₂ with the atmosphere on timescales of months to years.
This cycle is in approximate equilibrium — until disrupted by sudden changes in temperature, ocean circulation, or biological productivity.
The geological carbon cycle operates over millions of years. Volcanic outgassing releases CO₂ from the mantle. Chemical weathering of silicate rocks consumes it. Marine organisms incorporate carbon into shells (CaCO₃) that become limestone. Organic matter buried in sediments becomes fossil fuels.
Human activities release approximately ~37 GtCO₂/year into the atmosphere. The primary sources are fossil fuel combustion, industrial processes, and land-use change.
| Source | GtCO₂/year | Share |
|---|---|---|
| Energy (electricity & heat) | 15.0 |
|
| Transport | 8.7 |
|
| Industry | 6.3 |
|
| Buildings | 3.3 |
|
| Land use & forestry | 3.7 |
Since Charles David Keeling began measurements at Mauna Loa in 1958, atmospheric CO₂ has risen from 315 ppm to over 428 ppm — a 36% increase. The sawtooth pattern reflects the seasonal "breathing" of Northern Hemisphere forests.
Decarbonization pathways are not speculative — they are engineering and policy challenges with known solutions. The question is speed of deployment.
Solar and wind are now the cheapest new electricity sources in most markets. Combined with storage, they can replace >90% of fossil generation.
Heat pumps, EVs, and induction cooking replace direct fossil fuel use. Electrify everything, then clean the grid.
Direct air capture, enhanced weathering, and biochar. Necessary for hard-to-abate sectors and legacy emissions.
Reforestation, soil carbon, wetland restoration. Proven, cost-effective, with co-benefits for biodiversity.