Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

El Niño and La Niña Mix Up Plankton Populations

24.06.2005


El Niño and La Niña play with the populations of microscopic ocean plants called phytoplankton. That’s what scientists have found using NASA satellite data and a computer model.



Phytoplankton are the base of the marine food chain, providing food for little sea animals called zooplankton, which in turn feed fish and other creatures. Any change in phytoplankton numbers alters the ocean food chain.

The computer model showed that during El Niño periods, warm waters from the Western Pacific Ocean spread out over much of the ocean basin as upwelling weakens in the Eastern Pacific Ocean. Upwelling brings cool, nutrient-rich water from the deep ocean up to the surface. When the upwelling is weakened, there are less phytoplankton, making food more scarce for zooplankton that eat the ocean plants.


During La Niña conditions as in 1998, the opposite effect occurs as the easterly trade winds pick up and upwelling intensifies bringing nutrients like iron to the surface waters, which increases phytoplankton growth. Sometimes, the growth can take place quickly, developing into what scientists call phytoplankton "blooms."

In a study published in the January 2005 issue of Geophysical Research Letters, Wendy Wang and colleagues at the University of Maryland Earth System Science Interdisciplinary Center, College Park, Md., found that changes in phytoplankton amounts due to El Niño and La Niña not only affect the food chain, but also influence Earth’s climate.

As phytoplankton flourish during La Niña years, a large amount of carbon is used to build their cells during photosynthesis. The plants get carbon from carbon dioxide in surface waters. In the atmosphere, carbon dioxide is an important greenhouse gas. When marine organisms die, they carry carbon in their cells to the deep ocean. Surprisingly, this study found that this transfer of carbon to the deep ocean increased by a factor of eight due to the large phytoplankton blooms that can occur during a La Niña. At the same time, the effects of El Niños can reduce phytoplankton numbers, and decrease the impacts of this "biological carbon pump."

Using a computer model and NASA’s Sea-viewing Wide Field-of-view Sensor (SeaWiFS) satellite, Wang examined marine biological changes associated with El Niño and La Niña, and found the mechanisms responsible for such phytoplankton blooms. SeaWiFS measures the amount of light coming out of the ocean at different wavelengths on the spectrum, and can determine the strength of the greenness coming from the tiny plants’ cells.

When the El Niño of 1997-1998 became a La Niña beginning in mid-1998, SeaWiFS imagery showed extremely dark greenness along the equator. "[At that time SeaWifs showed] chlorophyll concentrations increasing by more than 500 percent, a level not previously observed," said Wang. The study found that because most microscopic animals called zooplankton died off during the El Niño there were less around to eat phytoplankton. That led to large phytoplankton blooms.

Besides influencing the marine food web, phytoplankton also help regulate the Earth’s climate by accounting for about half of the carbon dioxide, a major greenhouse gas, absorbed annually from the atmosphere by plants.

Rob Gutro | EurekAlert!
Further information:
http://www.nasa.gov/vision/earth/lookingatearth/plankton_elnino.html
http://www.gsfc.nasa.gov

More articles from Earth Sciences:

nachricht New insights into the ancestors of all complex life
29.05.2017 | University of Bristol

nachricht A 3-D look at the 2015 El Niño
29.05.2017 | NASA/Goddard Space Flight Center

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Strathclyde-led research develops world's highest gain high-power laser amplifier

The world's highest gain high power laser amplifier - by many orders of magnitude - has been developed in research led at the University of Strathclyde.

The researchers demonstrated the feasibility of using plasma to amplify short laser pulses of picojoule-level energy up to 100 millijoules, which is a 'gain'...

Im Focus: Can the immune system be boosted against Staphylococcus aureus by delivery of messenger RNA?

Staphylococcus aureus is a feared pathogen (MRSA, multi-resistant S. aureus) due to frequent resistances against many antibiotics, especially in hospital infections. Researchers at the Paul-Ehrlich-Institut have identified immunological processes that prevent a successful immune response directed against the pathogenic agent. The delivery of bacterial proteins with RNA adjuvant or messenger RNA (mRNA) into immune cells allows the re-direction of the immune response towards an active defense against S. aureus. This could be of significant importance for the development of an effective vaccine. PLOS Pathogens has published these research results online on 25 May 2017.

Staphylococcus aureus (S. aureus) is a bacterium that colonizes by far more than half of the skin and the mucosa of adults, usually without causing infections....

Im Focus: A quantum walk of photons

Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.

The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....

Im Focus: Turmoil in sluggish electrons’ existence

An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.

We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...

Im Focus: Wafer-thin Magnetic Materials Developed for Future Quantum Technologies

Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.

Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Marine Conservation: IASS Contributes to UN Ocean Conference in New York on 5-9 June

24.05.2017 | Event News

AWK Aachen Machine Tool Colloquium 2017: Internet of Production for Agile Enterprises

23.05.2017 | Event News

Dortmund MST Conference presents Individualized Healthcare Solutions with micro and nanotechnology

22.05.2017 | Event News

 
Latest News

New insights into the ancestors of all complex life

29.05.2017 | Earth Sciences

New photocatalyst speeds up the conversion of carbon dioxide into chemical resources

29.05.2017 | Life Sciences

NASA's SDO sees partial eclipse in space

29.05.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>