Partitioning of formaldehyde between air and ice at -35℃ to -5℃

摘要

The equilibrium partitioning of formaldehyde (HCHO) between air and snow was studied in a series of laboratory experiments conducted at -5℃, -15℃, and -35℃, in order to understand how partitioning of HCHO between air and polar snow varies with temperature, and thus seasonally on the ice sheet. Measured partitioning coefficients were 56, 93, and 245 mol l~(-1) atm~(-1) for -5℃, -15℃ and -35℃, respectively, showing a similar trend as the values previously estimated from field observations. Estimates of the pseudo-first-order rate coefficient for air-snow exchange for the same three temperatures were 4.1 × 10~(-4), 1.1 × 10~(-4), and 1.1 × 10~(-5) s~(-1), respectively.