Space Industry and Business News  
EARTH OBSERVATION
Space-based lidar shines new light on plankton
by Staff Writers
Corvallis OR (SPX) Dec 22, 2016


An artist's rendering shows a laser beam from a satellite-mounted LIDAR instrument probing the plankton-rich waters of Earth's northern and southern oceans. Image courtesy Tim Marvel, NASA. For a larger version of this image please go here.

A space-based sensor that can "see" through fog, clouds and darkness has given scientists their first continuous look at the boom-bust cycles that drive polar plankton communities. The decade-long set of images reveals that phytoplankton cycles are more tied to the push-pull relationship between them and their predators than was initially thought, according to a study published in the journal Nature Geoscience.

Phytoplankton are the foundation of the ocean's food web. Commercial fisheries, marine mammals and birds all depend on the blooms, said the study's lead author, Michael Behrenfeld, an expert in marine plankton at Oregon State University's College of Agricultural Sciences.

"It's really important for us to understand what controls these boom-bust cycles and how they might change in the future," Behrenfeld said, "because the dynamics of plankton communities have implications for all the other organisms throughout the web."

Phytoplankton also influence Earth's carbon cycle. Through photosynthesis, they absorb a great deal of the carbon dioxide near the ocean's surface. That, in turn, allows carbon dioxide from the atmosphere to go into the ocean.

The satellite-mounted LIDAR instrument, dubbed Cloud-Aerosol Lidar with Orthogonal Polarization, or CALIOP, uses a laser beam to map the ocean's surface and immediate subsurface. CALIOP monitored plankton in the Arctic and Antarctic ocean waters from 2006 to 2015.

CALIOP'S measurements reveal that, as the phytoplankton growth accelerates, the blooms are able to outpace the organisms that prey on them. As soon as that acceleration stops, however, the predatory organisms catch up and the bloom ends.

Imagine two rubber balls - one red, one green - connected by a rubber band, Behrenfeld said.

"Take the green ball - which represents the phytoplankton - and whack it with a paddle," he said. "As long as that green ball accelerates, the rubber band will stretch, and the red ball - which represents all the things that eat or kill the phytoplankton - won't catch up with the green ball. But as soon as the green ball stops accelerating, the tension in the rubber band will pull that red ball up to it, and the red ball catches up."

This finding, he said, goes against the commonly held belief that blooms begin when phytoplankton growth rates reach a threshold rate, and then stop when growth rates crash.

Instead, blooms start when growth rates are extremely slow, and then stop when phytoplankton growth is at its maximum but the acceleration of the bloom has hit its peak. It's only then that the predatory organisms catch up and the bloom terminates.

The study also reveals that, in Arctic waters, the year-to-year changes in this constant push and pull between predator and prey has been the primary driver of change over the past 10 years. The situation is different in the southern ocean around Antarctica, where changes in the ice cover held more sway.

"The take-home message," Behrenfeld said, "is that, if we want to understand the production of the polar systems as a whole, we have to focus both on changes in ice cover and changes in the ecosystems that regulate this delicate balance between predators and prey."

The capabilities of space-based LIDAR, he said, open the door to even more-detailed measurements of plankton communities. For example, the CALIOP instrument, good as it is, was engineered to take measurements of the atmosphere and does not have the resolution necessary to capture detailed information below the ocean's surface.

A higher-resolution instrument, now being developed at NASA but not yet deployed on a satellite, could collect subsurface samples at finely spaced depths as the laser pulse penetrates through the water column, allowing scientists to see the vertical structure of plankton blooms. That would reveal more about how plankton are being influenced by the ocean's currents and its other physical properties, Behrenfeld said.

The instrument could also determine what fraction of the signal is from the scattering of light versus the absorption of light.

"We can use the scattering information to quantify the concentration of the plankton, and we can use the absorption to say something about the plankton's physiology - in other words, the health of the cells," said Behrenfeld.

The CALIOP sensor is mounted on the CALIPSO satellite (Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation), jointly owned by NASA and France's space agency. Other participating institutions include the University of Maine, the University of California and Princeton University.

Research Report


Comment on this article using your Disqus, Facebook, Google or Twitter login.


Thanks for being here;
We need your help. The SpaceDaily news network continues to grow but revenues have never been harder to maintain.

With the rise of Ad Blockers, and Facebook - our traditional revenue sources via quality network advertising continues to decline. And unlike so many other news sites, we don't have a paywall - with those annoying usernames and passwords.

Our news coverage takes time and effort to publish 365 days a year.

If you find our news sites informative and useful then please consider becoming a regular supporter or for now make a one off contribution.
SpaceDaily Contributor
$5 Billed Once


credit card or paypal
SpaceDaily Monthly Supporter
$5 Billed Monthly


paypal only


.


Related Links
Oregon State University
Earth Observation News - Suppiliers, Technology and Application






Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle

Previous Report
EARTH OBSERVATION
Study of olivine provides new data for measuring earth's surface
Newark DE (SPX) Dec 16, 2016
Plate tectonics, the idea that the surface of the Earth is made up of plates that move apart and come back together, has been used to explain the locations of volcanoes and earthquakes since the 1960s. One well-known example of this is the Pacific Ring of Fire, a 25,000-mile stretch of the Pacific Ocean known for its string of underwater volcanoes (nearly 450 of them) and earthquake sites, accor ... read more


EARTH OBSERVATION
Discovery to inspire more radiation-resistant metals

Rice, Baylor team sets new mark for 'deep learning'

Method enables machine learning from unwieldy data sets

Microseeding: A new way to overcome hemihedral twinning?

EARTH OBSERVATION
Japan to Launch First Military Communications Satellite on January 24

Intelsat General to provide satellite services to RiteNet for US Army network

NSA gives Type1 certification to Harris radio

Upgraded telecommunications network for Marines

EARTH OBSERVATION
Russia to face strong competition from China in space launch market

Vega And Gokturk-1A are present for next Arianespace lightweight mission

Antares Rides Again

Four Galileo satellites are "topped off" for Arianespace's milestone Ariane 5 launch from the Spaceport

EARTH OBSERVATION
Europe's own satnav, Galileo, due to go live

Lockheed Martin and USAF move ahead with GPS backup ground system upgrade

OGC requests public comment on its Coverage Implementation Schema

Lockheed Martin Advances Modernization of Current GPS Ground Control System for USAF

EARTH OBSERVATION
Final sweep for MH370 sea search

Boeing delivers digital flight deck upgrades to NATO fleet

Raytheon contracted to repair F/A-18 weapon assemblies

US State Dept approves slew of ME defense deals

EARTH OBSERVATION
Fundamental solid state phenomenon unraveled

Movable microplatform floats on a sea of droplets

Fast track control accelerates switching of quantum bits

Stamping technique creates tiny circuits with electronic ink

EARTH OBSERVATION
Revolutions in understanding the ionosphere, Earth's interface to space

Researchers dial in to 'thermostat' in Earth's upper atmosphere

Study of olivine provides new data for measuring earth's surface

A look at the US cold snap from NASA infrared imagery

EARTH OBSERVATION
Mosul battle leaving legacy of environmental damage

China chokes under heavy smog with worse ahead

Beijing issues red alert for severe air pollution

Researchers create new way to trap dangerous gases









The content herein, unless otherwise known to be public domain, are Copyright 1995-2024 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. All articles labeled "by Staff Writers" include reports supplied to Space Media Network by industry news wires, PR agencies, corporate press officers and the like. Such articles are individually curated and edited by Space Media Network staff on the basis of the report's information value to our industry and professional readership. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. General Data Protection Regulation (GDPR) Statement Our advertisers use various cookies and the like to deliver the best ad banner available at one time. All network advertising suppliers have GDPR policies (Legitimate Interest) that conform with EU regulations for data collection. By using our websites you consent to cookie based advertising. If you do not agree with this then you must stop using the websites from May 25, 2018. Privacy Statement. Additional information can be found here at About Us.