Sevda Norouzi Alibabalou
Constraining the Global CO2 Flux Between Atmospheric and Water Stores
The uncertainty in the magnitude and direction of the global CO2 sink critically depends on improving our understanding of the gas transfer of climate active gases across the air-water interface. Recent estimates are not well constrained and fundamentally hampered by a lack of reliable measurements of pCO2 and gas transfer velocities (kw). Direct pCO2 measurements remain scarce so pCO2 is typically calculated from proxy variables, such as temperature, pH and total alkalinity.
However, there is uncertainty where there is a large contribution of organic acids and reduced buffering capacity in lower pH environments. The key to better understand and quantify these effects is kw. Kw cannot be measured directly and is typically parameterized using wind speed or river scaling laws. However, non-linear, highly divergent relations result as both variables are weak kw predictors. A targeted approach is required to advance novel in-situ technologies to produce high temporally resolved data to estimate kw.
Ryan Pereira and Alan M. MacDonald