Table 3. Top-down studies used in this study with their contribution to the decadal and yearly estimates. For decadal means, top-down studies have to provide at least 6 years over the decade to contribute to the estimate. All top-down studies provided both total and per categories (including soil uptake) partitioning.
Source: Earth System Science Data
URL:     http://www.earth-syst-sci-data.net/8/697/2016/essd-8-697-2016.pdf
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