Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

cean surface saltiness influences el nino forecasts

30.01.2003




NASA sponsored scientists have discovered by knowing the salt content of the ocean’s surface, they may be able to improve the ability to predict El Nino events. Scientists, studying the western Pacific Ocean, find regional changes in the saltiness of surface ocean water correspond to changes in upper ocean heat content in the months preceding an El Nino event. Knowing the distribution of surface salinity may help predict events.

Salinity and temperature combine to dictate the ocean’s density. Greater salinity, like colder temperatures, results in an increase in ocean density with a corresponding depression of the sea surface height. In warmer, fresher waters, the density is lower resulting in an elevation of the sea surface. These ocean height differences are related to the circulation of the ocean.

The surface salinity in two regions contributes to El Nino events: an area of warmer temperatures and lower salinity in the western Pacific, and the higher salinity and cooler temperatures in the eastern Pacific. Differences in surface salinity are related to changes in temperature and upper ocean heat content, which are part of the El Nino phenomenon. They have the potential to influence the Earth’s climate through air-sea interaction at the ocean’s surface.



The study, conducted for NASA by University of Maryland researchers Joaquim Ballabrera, Tony Busalacchi, and Ragu Murtugudde, is one of the first to look at ocean salinity in El Nino, Southern Oscillation (ENSO) predictions and their relationship to tropical sea surface temperatures, sea level, winds, and fresh water from rain. Results of the study are in the latest issue of the Journal of Geophysical Research - Oceans.

Ballabrera and his colleagues looked at data, from 1980 to 1995, about sea surface temperatures, winds, rainfall, evaporation, sea surface height, and latent heat, the energy released when water vapor condenses into droplets.

Using computer models, they performed a series of statistical predictions of the El Nino events for such a period. The results indicate short-term predictions only require monitoring sea surface temperatures, while predictions over a season require the observation of sea level. They concluded observations of salinity significantly improve predictions. When changes in salinity occur, they affect the El Nino event for the next six to 12 months. In this lag time, salinity changes have the potential to modify the layers of the ocean and affect the heat content of the western Pacific Ocean; the region where the unusual atmospheric and oceanic behavior associated to El Nino first develops. "As a result, when changes in ocean saltiness are considered, improvements are found in El Nino forecasts six to 12 months in advance," Ballabrera said.

"This research holds tremendous potential for the NASA Aquarius mission to monitor the surface salinity of the global ocean," Busalacchi said. Aquarius is scheduled for launch during 2006-2007. Aquarius will provide the first global maps of salt concentration on the ocean surface. Salt concentration is a key area of scientific uncertainty in the oceans’ capacity to store and transport heat, which in turn affects Earth’s climate and water cycle.

By using remote sensing data from satellites, scientists will be able to see changes in ocean salinity. Knowing the lag time factor, computer models simulating the movement of the atmosphere may be able to accurately predict El Nino episodes. This may lead to longer lead-time for predictions of ENSO events.

Florida State University, the National Center for Environmental Prediction, National Center for Atmospheric Research and the Etudes Climatiques de l’Ocean Pacifique tropical program at Institut de Recherche pour le Developpement, Centre de Noumea contributed ocean and atmosphere data to this study.

The National Oceanic and Atmospheric Administration’s El Nino Web Page:
http://www.pmel.noaa.gov/tao/elNino /Nino -home-low.html

Rob Gutro | NASA Goddard Space Flight Cente
Further information:
http://www.gsfc.nasa.gov/topstory/2003/0114salt.html
http://essic.umd.edu/~joaquim/salinity/
http://www.pmel.noaa.gov/tao/elNino /Nino -home-low.html

More articles from Earth Sciences:

nachricht Stagnation in the South Pacific Explains Natural CO2 Fluctuations
23.02.2018 | Carl von Ossietzky-Universität Oldenburg

nachricht First evidence of surprising ocean warming around Galápagos corals
22.02.2018 | University of Arizona

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Attoseconds break into atomic interior

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...

Im Focus: Good vibrations feel the force

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...

Im Focus: Developing reliable quantum computers

International research team makes important step on the path to solving certification problems

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...

Im Focus: In best circles: First integrated circuit from self-assembled polymer

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...

Im Focus: Demonstration of a single molecule piezoelectric effect

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...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

2nd International Conference on High Temperature Shape Memory Alloys (HTSMAs)

15.02.2018 | Event News

Aachen DC Grid Summit 2018

13.02.2018 | Event News

How Global Climate Policy Can Learn from the Energy Transition

12.02.2018 | Event News

 
Latest News

Basque researchers turn light upside down

23.02.2018 | Physics and Astronomy

Finnish research group discovers a new immune system regulator

23.02.2018 | Health and Medicine

Attoseconds break into atomic interior

23.02.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>