Now, a marine geochemist at the Woods Hole Oceanographic Institution (WHOI) has published a report in the latest issue of the journal Science that evaluates the total impact of such factors on the ocean and considers what the future might hold.
"What we do on land—agriculture, fossil fuel combustion and pollution—can have a profound impact on the chemistry of the sea," says Scott C. Doney, a senior scientist at WHOI and author of the Science report. "A whole range of these factors have been studied in isolation but have not been put in a single venue."
Doney's paper represents a meticulous compilation of the work of others as well as his own research in this area, which includes ocean acidification, climate change, and the global carbon cycle.
He concludes that climate change, rising atmospheric carbon dioxide, excess nutrient inputs, and the many forms of pollution are "altering fundamentally the…ocean, often on a global scale and, in some cases, at rates greatly exceeding those in the historical and recent geological record."
The research documents several major trends, which include a shift in the acid-based chemistry of seawater, reduced subsurface oxygen, both in coastal waters and the open ocean, rising coastal nitrogen levels, and a widespread increase in mercury and other pollutants.
"Human impacts are not isolated to coastal waters," Doney says. They "are seen around the globe."
Moreover, he says, "many of these changes in climate and ocean chemistry can compound each other, making the problem considerably worse for marine life." For example, warming and nutrient runoff both can trigger a decline in oxygen levels off the coast, according to Doney. And acidification, he says, may exacerbate coral bleaching.
Among Doney's findings:
Global ocean pH and chemical saturation states are changing at an "unprecedented" rate, 30 to 100 times faster than temporal changes in the recent geological past, "and the perturbations will last many centuries to millennia."
"Ocean acidification will likely reduce shell and skeleton growth by many marine calcifying species, including corals and mollusks."
"Ocean acidification may also reduce the tolerance of some species to thermal stress…Polar ecosystems may be particularly susceptible…"
Fertilizer runoff and nitrogen from fossil fuels are increasing the severity and duration of coastal hypoxia, or decreased oxygen.
Doney was part of an international consortium of scientists that reported recently that carbon dioxide emissions from fossil fuels have increased by almost a third over the last decade, rendering the Earth's future uncertain unless "CO2 emissions [are] drastically reduced."
They attributed the rise to increasing production and trade of manufactured products, particularly from emerging economies, the gradual shift from oil to coal, and the planet's waning capacity to absorb CO2.
Doney led a team that developed ocean-model simulations for estimating the historical variations in air-sea CO2 fluxes. "Over the last decade, CO2 emissions have continued to climb despite efforts to control emissions," Doney said. "Preliminary evidence suggests that the land and ocean may be becoming less effective at removing CO2 from the atmosphere, which could accelerate future climate change."
In his Science paper, Doney calls for "a deeper understanding of human impacts on ocean biogeochemistry…Although some progress has been made on a nascent ocean observing system for CO2, the marine environment remains woefully undersampled for most compounds. The oceanographic community needs to develop a coordinated observational plan…"
More detailed studies are needed, in particular, to look at the responses of cells and organisms to biochemical intruders to their undersea environment. "Lastly, Doney says, "targeted research is needed on the impacts on marine resources and fisheries, potential adaptation strategies, and the consequences for human and social economic systems."
The work was funded by WHOI and the Center for Microbial Oceanography, Research and Education.
The Woods Hole Oceanographic Institution is a private, independent organization in Falmouth, Mass., dedicated to marine research, engineering, and higher education. Established in 1930 on a recommendation from the National Academy of Sciences, its primary mission is to understand the oceans and their interaction with the Earth as a whole, and to communicate a basic understanding of the oceans' role in the changing global environment.
Media Relations | EurekAlert!
By saving cost and energy, the lighting revolution may increase light pollution
23.11.2017 | Helmholtz-Zentrum Potsdam - Deutsches GeoForschungsZentrum GFZ
Frictional Heat Powers Hydrothermal Activity on Enceladus
23.11.2017 | Universität Heidelberg
Heat from the friction of rocks caused by tidal forces could be the “engine” for the hydrothermal activity on Saturn's moon Enceladus. This presupposes that...
The WHO reports an estimated 429,000 malaria deaths each year. The disease mostly affects tropical and subtropical regions and in particular the African continent. The Fraunhofer Institute for Silicate Research ISC teamed up with the Fraunhofer Institute for Molecular Biology and Applied Ecology IME and the Institute of Tropical Medicine at the University of Tübingen for a new test method to detect malaria parasites in blood. The idea of the research project “NanoFRET” is to develop a highly sensitive and reliable rapid diagnostic test so that patient treatment can begin as early as possible.
Malaria is caused by parasites transmitted by mosquito bite. The most dangerous form of malaria is malaria tropica. Left untreated, it is fatal in most cases....
The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.
Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...
Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.
That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...
Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.
During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....
15.11.2017 | Event News
15.11.2017 | Event News
30.10.2017 | Event News
23.11.2017 | Information Technology
23.11.2017 | Physics and Astronomy
23.11.2017 | Life Sciences