Scientists at the UK Meteorological Office (Met Office) have released a new paper this week indicating the recent slowdown of the North Atlantic Ocean current system is natural, and not due to man-made global warming. Over the past ten years, the Atlantic meridional overturning circulation (AMOC), which includes the Gulf Stream, appeared to be decelerating, causing scientists to worry that this was a result of climate change.
This new Met Office research, published in the journal Nature Geoscience, shows that the slowdown trend is likely due to the current’s natural recovery from an earlier acceleration. Laura Jackson, the lead author of the paper, said in a press release that the AMOC plays a vital role in the climate because it carries heat north, keeping Europe relatively warm.
The science behind the research
By utilizing state-of-the-art modeling of ocean dynamics and ocean observations from satellites, the Met Office re-examined the Gulf Stream current from scratch. They analyzed the ocean using floats that sat just below the surface. They also captured year-over-year deviations and recent decade-long trends with impeccable accuracy. Jackson also said their research provided a snapshot of how the ocean changes over decadal time spans. The new analysis reproduces the observed slowdown in the AMOC over the past decade, but “finds that this was preceded by a period where the current was faster.” This implies that the AMOC runs on ten-year-long intervals, and that natural variability played the primary role in the AMOC’s weakened circulation.
Natural, long-term changes in the ocean and not global warming are behind the well-publicized slowdown in the Gulf Stream that scientists observed in recent years. This slowdown was used for dramatic effect in the climatastrophe flick ‘The Day after Tomorrow,’ in which fresh water from melted Arctic sea ice drained into the Atlantic Ocean and shut down the AMOC, sending the planet into a new Ice Age. The current is responsible for both eastern America and western Europe’s somewhat habitable weather. Without it, both coasts would fall into a prolonged deep freeze during winter.