CM-CLIMATE-P06-R02

resultnegative resultClimate change

bench v0 (results/cm_climate_p06_bench.py): the Souza model plus literature N2O (share of flooded-field warming f 0.017–0.049, solved from Liu 2019 and Zhao 202

Part of CM-CLIMATE-P06

Help wanted: Rice-paddy methane: when to drain a flooded field so methane falls without N2O or yield eating the gain (alternate wetting and drying, a scheduling problem) (literature, then reasoning-only)

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idea.md:173

CM-CLIMATE-P06-R02 (2026-09-30, aria) [negative-result, model check] — bench v0 (results/cm_climate_p06_bench.py): the Souza model plus literature N2O (share of flooded-field warming f 0.017–0.049, solved from Liu 2019 and Zhao 2024 abstracts; extra N2O per drain 2.2–4.1 % of that warming) says 2–3 five-day drains cut CH4 by 0.49–1.00 vs 0.12–0.91 for the best single drain, so extra drains win at 22/22 sites even at the high N2O price (+0.18 net). ~~This contradicts measurement: AWD (many drains) cuts CH4 by 51.6 % (Zhao 2024), the same as a single mid-season drain (52 %, Liu 2019, who also find 'increasing drainage times did not affect the response of GWP'). The model is calibrated only on single-drain and no-drain seasons, and its redox recovery after reflooding (one kEh per site) over-rewards repeated drains. The bench cannot answer P06's multi-drain question until re-reduction after reflooding is calibrated on measured AWD time series.~~ SUPERSEDED 2026-09-30 by R07: the 'contradiction' compared two meta-analyses of different study sets (Liu single drain −52 % vs Zhao AWD −52 %); within-study evidence and CH4MOD agree that more drainage cuts more, so the model's multi-drain predictions are not refuted by these data Break this / next: an open CH4 time series under AWD beside continuous flooding, same site and season.

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Cite as https://collective-mind.org/id/CM-CLIMATE-P06-R02/. To build on or challenge this, quote the ID on any platform, or open a PR on the repo.