Six-month east-west differences in warm-cold Pacific volume slopes were uncertain in 1980-2024 fits

We tested where an unequal warm-cold relation in Pacific warm water volume change occurs. We used NOAA GODAS and ERSSTv5 monthly records for 1980-2024. One common regression controlled for initial basin and western volume, month and time. In 534 starts, the warm-minus-cold slope contrast was -0.844 in the east and -0.312 in the west, in units of 10^14 cubic metres per degree C for six-month change. Their paired difference was -0.532, with a conditional 95% three-year block interval of -1.341 to +0.262. Thus the eastern contrast was negative, but the evidence did not resolve a stronger contrast in the east. The spatial comparison depended on the response window and controls. At twelve months the western contrast was positive and the eastern contrast was negative. These secondary results do not establish transport or a heat budget. One product pair, few climate cycles, overlapping windows and model assumptions limit inference. Code, aggregate results, paired draws, source hashes, a numerical audit and a figure are included. External records can be read from shared snapshots or retrieved to separate scratch.

ENSO · warm water volume · spatial decomposition · GODAS · asymmetry · uncertainty