Researchers map a current system that had been assumed stable
A decade of moored sensors shows seasonal variation far larger than models predicted, with consequences for regional forecasts.
The array was installed to confirm something everyone believed. Instead it found a system that swings far more than the textbooks allow.
Moorings deployed across the basin recorded transport volumes varying by a factor the research team described as "uncomfortably large" between seasons, with a trend over the decade that the data set is still too short to call significant.
The finding matters because regional climate models treat this circulation as a relatively steady boundary condition. If it is not steady, seasonal forecasts for several densely populated coastlines inherit an error nobody had budgeted for.
The team is careful about what the record does and does not show. Ten years is a short window for an ocean process, and the apparent trend could be a long oscillation caught at an awkward moment.
Funding for the array runs out in two years. The group has applied for an extension on the grounds that the only thing worse than a ten-year record is a ten-year record that stops.
