Deep ocean communities impacted by changing climate over 24 y in the abyssal northeast Pacific Ocean

Significance Global warming is now a well-documented phenomenon that is influencing every aspect of our world, from increased storm intensity to melting of polar ice sheets and rising sea level. The impact of such changes in climate is least known for the deep ocean, which covers over 60% of the earth’s surface. An unprecedented 24-y time series measuring changes in food supply and utilization by benthic communities at 4,000-m depth in the deep northeast Pacific reveal strong connectivity with changing surface ocean conditions, which have broad implications for the global carbon cycle. The deep ocean, covering a vast expanse of the globe, relies almost exclusively on a food supply originating from primary production in surface waters. With well-documented warming of oceanic surface waters and conflicting reports of increasing and decreasing primary production trends, questions persist about how such changes impact deep ocean communities. A 24-y time-series study of sinking particulate organic carbon (food) supply and its utilization by the benthic community was conducted in the abyssal northeast Pacific (∼4,000-m depth). Here we show that previous findings of food deficits are now punctuated by large episodic surpluses of particulate organic carbon reaching the sea floor, which meet utilization. Changing surface ocean conditions are translated to the deep ocean, where decadal peaks in supply, remineralization, and sequestration of organic carbon have broad implications for global carbon budget projections.