Layers of salty ocean water mix with layers of fresher water, creating a salty staircase or layering driven by small-scale convection known as salt fingers. Although scientists have known about salt fingers since 1960, when they were discovered at the Woods Hole Oceanographic Institution, they have not understood their role in ocean mixing and the ability of the ocean to absorb heat, carbon dioxide and pollutants from the atmosphere. Results of a new experiment, sponsored by the National Science Foundation and reported in todays issue of Science, indicate that salt fingers are vertically mixing ocean waters more than previously thought. The finding will improve understanding of how water masses in the ocean mix, leading to better climate prediction models.
Researchers from the Woods Hole Oceanographic Institution (WHOI) studied salt fingers by injecting a dye or tracer into the ocean, much like dyes are used in medical tests to trace bodily fluids. The tracer was released from an injection sled towed at a depth of approximately 400 meters (about 1,200 feet) from a ship in the tropical Atlantic near Barbados. Returning to the area nine months later, they found a significant vertical spread of the tracer indicating an enhanced mixing process, with salt and the tracer mixing twice as much as heat.
In this region, warm, high salinity subtropical water lies over cooler, fresher water flowing northward from Antarctica, creating a unique stratification with distinct layers of water. As many as ten to fifteen layers, each 10 to 30 meters thick (roughly 30 to 90 feet) with uniform temperature and salinity, are separated by interfaces with rapidly changing temperature and salinity, half a meter to 5 meters (about 2 feet to 10 feet) thick, to form a "thermohaline staircase" of sorts. The process known as salt fingers occurs at the interfaces and keeps the mixed layers uniform.
Shelley Dawicki | EurekAlert!
Stagnation in the South Pacific Explains Natural CO2 Fluctuations
23.02.2018 | Carl von Ossietzky-Universität Oldenburg
First evidence of surprising ocean warming around Galápagos corals
22.02.2018 | University of Arizona
A newly developed laser technology has enabled physicists in the Laboratory for Attosecond Physics (jointly run by LMU Munich and the Max Planck Institute of Quantum Optics) to generate attosecond bursts of high-energy photons of unprecedented intensity. This has made it possible to observe the interaction of multiple photons in a single such pulse with electrons in the inner orbital shell of an atom.
In order to observe the ultrafast electron motion in the inner shells of atoms with short light pulses, the pulses must not only be ultrashort, but very...
A group of researchers led by Andrea Cavalleri at the Max Planck Institute for Structure and Dynamics of Matter (MPSD) in Hamburg has demonstrated a new method enabling precise measurements of the interatomic forces that hold crystalline solids together. The paper Probing the Interatomic Potential of Solids by Strong-Field Nonlinear Phononics, published online in Nature, explains how a terahertz-frequency laser pulse can drive very large deformations of the crystal.
By measuring the highly unusual atomic trajectories under extreme electromagnetic transients, the MPSD group could reconstruct how rigid the atomic bonds are...
Quantum computers may one day solve algorithmic problems which even the biggest supercomputers today can’t manage. But how do you test a quantum computer to...
For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.
In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...
Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale
Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...
15.02.2018 | Event News
13.02.2018 | Event News
12.02.2018 | Event News
23.02.2018 | Physics and Astronomy
23.02.2018 | Health and Medicine
23.02.2018 | Physics and Astronomy