Ideas and Perspectives Human breath raises the atmospheric CO2 and
affects the climate
The CO2 emission of human breath will not increase the CO2 of the
atmosphere and raise the temperature, or so science journalists
forcefully claim, because the emission is recycled by green plants,
which take up CO2 to generate our food. Emission and retrieval are
assumed to be in perfect balance, no CO2 is left to escape into the
atmosphere. This faulty argument dominated the literature for years. A
correct analysis would take all CO2 fluxes into account. It would add
the simultaneous emissions, including the emission of breath (B) and
subtract from this sum (S) the fluxes of all sinks (P) to obtain the
overall flux of CO2 escaping into the atmosphere per year (S-P). Then
the escape-flux due to breath-emission is found to be b = B (1 - P/S).
Thus human breath increases the atmospheric CO2 , after all.