Plain Language Summary
Since the industrial revolution, human-induced excess carbon dioxide (Cant)
has been disrupting the carbon cycle. The ocean absorbs part of it, reducing
atmospheric excess but causing severe consequences for marine systems.
Oceanic Cant storage is uneven, and estimates rely on indirect methods due
to the impossibility of an analytical procedure for discerning the signal. To date,
there is no optimal method for calculating Cant. Progress is essential, and
advancements are needed across various approaches. Back-calculation
methods differ from the rest by using marine-carbonate-system (MCS) data,
and their results serve as observational references. In this study, we present
a novel approach for estimating marine Cant globally, which relies on an
improved back-calculation formulation and is based exclusively on
climatological MCS high-quality data. Our resulting Cant climatology
agrees with previous global studies, underscoring the feasibility of our
approach and emphasizing the relevance of accurate MCS data for climate
change related research.
Key Points
- We present a method for estimating ocean anthropogenic carbon
based on marine carbonate system data and a water mass mixing
framework
- Key advantages of our method include reliance on climatologies
derived from accurate observations and accounting for oxygen
disequilibrium
- We determined a global ocean anthropogenic carbon inventory
of 124 ± 7 Pg C referred to 1995, consistent with estimates from