Bleaching above 10% had a larger heat slope in Pacific repeat-site surveys in 2011-2019 under country clusters

We split reported coral bleaching into a part capped at 10% and an excess part. Four Atlantic and Pacific repeat-site models used 5,336 monthly units in 2003-2019. Only the later Pacific excess slope clearly exceeded its capped slope after four-test adjustment: +2.11 bleaching points per four TSA degree-heating weeks, with an interval of +0.42 to +3.80. The other three intervals included zero. The later Pacific interval included zero with same-site, same-calendar-month comparisons and after removal of high heat doses. Results also depended on the chosen split. The method keeps zero and mild cases and gives an exact additive slope check. Selected reports, missing visits, limited heat support, and changing detection limit inference. The result does not establish causal warming damage, species loss, or a pollution effect. The package includes source hashes, monthly evidence, code, checks, and a figure.

coral bleaching · heat stress · observation bias · slope decomposition · regional replication