Since the 1980’s Dr. Joseph M. Prospero, professor of Marine and Atmospheric Chemistry at the University of Miami’s Rosenstiel School of Marine and Atmospheric Science, has pioneered studies in the worldwide measurement of aerosols, fine particles suspended in the atmosphere and carried by winds.
His team’s work focuses on the aerosol chemistry of the marine atmosphere. They are particularly interested in the long-range transport of pollutants from the continents to the oceans and their impact on climate and on biogeochemical processes in ocean waters.
Starting in 1980 Prospero established a network of island stations in the North and South Pacific Oceans. These stations made continuous measurements of the concentration of major aerosol species that play a role in climate: mineral dust, nitrate, sulfate, and sea salt. The network was eventually extended to the Indian Ocean and Antarctica. Throughout the 80’s and into the late 90’s the UM team maintained a total of 30 stations in constant operation in all ocean regions. The data obtained are unique and they have played a critical role in the development and testing of the global chemical transport models used in the recent climate assessment carried out by Intergovernmental Panel on Climate Change.
Prospero’s data plays a central role in a paper that appears in the May 16 issue of Science, “Impacts of Atmospheric Anthropogenic Nitrogen on the Open Ocean”. Spearheaded by Dr. Robert Duce from Texas A&M, the study highlights the importance of the Earth’s nitrogen cycle, and its vital link to the global carbon cycle, especially the atmospheric concentration of CO2, the greenhouse gas responsible for most of the global warming effects observed during the past century.
Scientists have long known that biological processes in the ocean play an important role in the global carbon cycle. Algae and other forms of marine life take up CO2 and nutrients from ocean surface waters and, through the process of photosynthesis, reproduce and grow rapidly in total mass. This process draws CO2 from the atmosphere and partially offsets the growth of CO2 from human activities. Every year approximately one-third of the CO2 released into the atmosphere because of human activities, is taken up by the oceans.
Consequently any processes that affect the ocean uptake of CO2 can have an effect on global warming.
Various nitrogen compounds, especially nitrates and ammonium, play an important role in ocean’s photosynthesis by acting as fertilizers that stimulate the growth of marine organisms. Because of human activities, the emission rates of these compounds have increased greatly over the last 100 years. The transport of these compounds to the oceans, mostly through the atmosphere, have acted to increase the draw-down of CO2 from the atmosphere.
The paper in Science compares emissions of nitrogen compounds in the year 1860, before humans had a great impact on pollution emissions, with current emissions. Today pollutant nitrogen deposition to the oceans accounts for about ten percent of the draw-down of CO2 from the atmosphere to the ocean. However, the deposition of these pollutants also results in the increased emissions of nitrous oxide, N2O, which is also a potent greenhouse gas. The net effect is that the N2O emissions offset about one-third of the effects of the increased drawdown of CO2 due to pollution deposition.
The team who wrote the paper appearing in Science also estimates emissions for the year 2020 using scenarios from the IPCC report. “All of us are concerned that the amount of anthropogenic nitrogen transported to the oceans will to continue to rise in the future,” commented Prospero.
Founded in the 1940's, the University of Miami's Rosenstiel School of Marine & Atmospheric Science has grown into one of the world's premier marine and atmospheric research institutions. Offering dynamic interdisciplinary academics, the Rosenstiel School is dedicated to helping communities to better understand the planet, participating in the establishment of environmental policies, and aiding in the improvement of society and quality of life. The School currently has more than 1,300 alumni around the globe.
Barbra Gonzalez | EurekAlert!
In times of climate change: What a lake’s colour can tell about its condition
21.09.2017 | Leibniz-Institut für Gewässerökologie und Binnenfischerei (IGB)
Did marine sponges trigger the ‘Cambrian explosion’ through ‘ecosystem engineering’?
21.09.2017 | Helmholtz-Zentrum Potsdam - Deutsches GeoForschungsZentrum GFZ
Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.
The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...
Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...
Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!
When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...
For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.
Multiferroics are materials that simultaneously react to electric and magnetic fields. These two properties are rarely found together, and their combined...
MBM ScienceBridge GmbH successfully negotiated a license agreement between University Medical Center Göttingen (UMG) and the biotech company Tissue Systems Holding GmbH about commercial use of a multi-well tissue plate for automated and reliable tissue engineering & drug testing.
MBM ScienceBridge GmbH successfully negotiated a license agreement between University Medical Center Göttingen (UMG) and the biotech company Tissue Systems...
19.09.2017 | Event News
12.09.2017 | Event News
06.09.2017 | Event News
21.09.2017 | Physics and Astronomy
21.09.2017 | Life Sciences
21.09.2017 | Health and Medicine