CO2vel

CO2vel is a term used in some niche contexts to describe a velocity‑like characteristic of carbon dioxide movement or change in a medium. It is not a standard term with a universally accepted definition, and its meaning can vary between disciplines or applications.

In indoor environments, CO2vel is often used to refer to the effective speed at which CO2 introduced by occupants or sources is transported and diluted by ventilation. This usage combines measurements of CO2 concentration with known air flow rates to convey how quickly a CO2 plume disperses, without naming a specific physical quantity. In outdoor atmospheric studies, CO2vel may describe the apparent rate of change of CO2 concentration along a flow path, serving as an intuitive descriptor of transport rather than a fundamental meteorological variable.

Measurement and calculation of CO2vel are typically inferred from CO2 concentration data collected by sensors, sometimes alongside wind or airflow data. Calculations may involve time series analysis, tracer methods, or estimation of plume front movement to yield a velocity‑like parameter. The resulting quantity often has units that depend on the chosen definition, which can hinder cross‑study comparisons if the definition is not explicitly stated.

Applications of CO2vel include communicating about ventilation effectiveness and plume transport in a qualitative sense. However, the lack of standardization means careful specification of the definition, measurement approach, and units is essential to avoid confusion with established concepts such as CO2 concentration or CO2 flux.

See also: CO2 concentration, CO2 flux, eddy covariance, indoor air quality, ventilation.