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 Predicting unpredictability: Information theory offers new way to read ice cores
07.12.2016 | Santa Fe Institute

nachricht Sea ice hit record lows in November
07.12.2016 | University of Colorado at Boulder

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Significantly more productivity in USP lasers

In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.

Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

Closing the carbon loop

08.12.2016 | Life Sciences

Applicability of dynamic facilitation theory to binary hard disk systems

08.12.2016 | Physics and Astronomy

Scientists track chemical and structural evolution of catalytic nanoparticles in 3-D

08.12.2016 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>