A study examines how agriculture influences mortality due to poor air quality in the United States.
Image credit: Jason D. Hill.
Edited by David M. Karl, University of Hawaii, Honolulu, HI, and approved October 8, 2013 (received for review August 14, 2013)
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.
Abstract
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.
Footnotes
- ↵1To whom correspondence should be addressed. E-mail: ksmith{at}mbari.org.
Author contributions: K.L.S., H.A.R., and A.D.S. designed research; K.L.S., H.A.R., M.K., C.L.H., and A.D.S. performed research; K.L.S. and A.D.S. contributed new analytic tools; K.L.S., H.A.R., M.K., C.L.H., and A.D.S. analyzed data; and K.L.S., H.A.R., M.K., C.L.H., and A.D.S. wrote the paper.
The authors declare no conflict of interest.
This article is a PNAS Direct Submission.
This article contains supporting information online at www.pnas.org/lookup/suppl/doi:10.1073/pnas.1315447110/-/DCSupplemental.
Freely available online through the PNAS open access option.
Climate change and food supply to the deep ocean
Sign up for Article Alerts
Jump to section
You May Also be Interested in
Researchers report a unique quasicrystal discovered in the remnants of the first nuclear bomb detonation.
Image credit: Luca Bindi and Paul J. Steinhardt.
A study estimates that there are 50 billion birds in the world, with the majority in palearctic and nearctic realms.
Image credit: Corey T. Callaghan.
People are increasingly dividing themselves into social and political factions. Models can hint at how it happens—and maybe offer ways to mitigate it.
Image credit: Dave Cutler (artist).
A computer visualization of the fossilized plant Asteroxylon mackiei could potentially offer clues as to how modern plants emerged.
Image credit: Matt Humpage (artist).