Carbonleaving

Carbonleaving is a term used in environmental science to describe the net efflux of carbon from a defined system to another reservoir, most often from terrestrial or aquatic ecosystems to the atmosphere or the ocean. It is a component of carbon budgeting and climate modeling, representing the amount of carbon that leaves a system over a given time period. The phrase is not universally standardized, and its exact definition may vary between studies or disciplines.

Mechanisms contributing to carbonleaving include respiration by plants and soil microbes, the decay of organic matter, wildfires, and other forms of combustion. In the atmosphere–ocean and atmosphere–land interfaces, physical processes such as gas exchange and outgassing also transport carbon away from a system. In forests and soils, soil respiration and rapid decomposition can be dominant pathways, while in oceans, exchange of CO2 and methane with the atmosphere can drive significant carbon fluxes in either direction depending on conditions.

Measurement of carbonleaving fluxes typically uses units of carbon per time, commonly gigatons of carbon per year (GtC/yr). Methods include in situ chamber measurements and eddy covariance for ecosystems, isotopic tracing, and modeling approaches that integrate satellite and in situ data to estimate large-scale fluxes.

Relation to broader concepts: carbonleaving is related to, but distinct from, carbon emissions, sequestration, and general carbon flux. It focuses on the net movement of carbon out of a defined system, contributing to understanding of regional and global carbon cycles and informing climate policy and ecological management. See also carbon cycle, carbon flux, carbon sequestration, and greenhouse gas emissions.