Monthly Distribution of Sea-Air pCO2 Differences over the Global Ocean

They were obtained using each of two schemes to correct observations to a reference year of 1990, named, respectively, dp90 (full correction) and hf90 (half correction). The first assumes that pCO2 in high latitude surface waters changed seasonally, but not from year to year, due to convective mixing with deep waters.

The second assumes that pCO2 in high latitude waters increased yearly at a rate half of that observed for atmospheric CO2. In addition, one file shows a map of the net CO2 flux over the oceans for the reference year of 1990. This has been computed using "full correction" sea-air pCO2 difference for each month, the monthly climatological wind speed assembled by Esbensen and Kushnir, and the effect of wind speeds on the CO2 gas transfer coefficient formulated by Wanninkhof.