Free Newsletters - Space - Defense - Environment - Energy - Solar - Nuclear
..
. 24/7 Space News .




ICE WORLD
Study shows iron from melting ice sheets may help buffer global warming
by Staff Writers
Brussels, Belgium (SPX) May 26, 2014


The flux of bioavailable iron associated with glacial runoff is between 400,000 and 2,500,000 tonnes per year in Greenland and between 60,000 and 100,000 tonnes per year in Antarctica.

A newly-discovered source of oceanic bioavailable iron could have a major impact our understanding of marine food chains and global warming. A UK team has discovered that summer meltwaters from ice sheets are rich in iron, which will have important implications on phytoplankton growth. The findings are reported in the journal Nature Communications.

It is well known that bioavailable iron boosts phytoplankton growth in many of the Earth's oceans. In turn phytoplankton capture carbon - thus buffering the effects of global warming. The plankton also feed into the bottom of the oceanic food chain, thus providing a food source for marine animals.

The team, comprising researchers from the Universities of Bristol, Leeds, Edinburgh and the National Oceanography Centre, collected meltwater discharged from the 600 km2 Leverett Glacier in Greenland over the summer of 2012, which was subsequently tested for bioavailable iron content.

The researchers found that the water exiting from beneath the melting ice sheet contained significant quantities of previously-unconsidered bioavailable iron. This means that the polar oceans receive a seasonal iron boost as the glaciers melt.

Jon Hawkings (Bristol), the lead author, said "The Greenland and Antarctic Ice Sheets cover around 10% of global land surface. Iron exported in icebergs from these ice sheets have been recognised as a source of iron to the oceans for some time. Our finding that there is also significant iron discharged in runoff from large ice sheet catchments is new. "

"This means that relatively high iron concentrations are released from the ice sheet all summer, providing a continuous source of iron to the coastal ocean"

Iron is one of the most important biochemical elements, due to its impact on ocean productivity. Despite being the fourth most abundant element in the Earth's crust, it is mostly not biologically available because it is largely present as unreactive minerals in natural waters.

Over the last 20 years there has been controversy over the role of iron in marine food chains and the global carbon cycle, with some groups experimenting with dumping iron into the sea in order to accelerate plankton growth - with the idea that increased plankton growth would capture man made CO2. This work indicates that ice sheets may already be carrying out this process every summer.

Based on their results the team estimates that the flux of bioavailable iron associated with glacial runoff is between 400,000 and 2,500,000 tonnes per year in Greenland and between 60,000 and 100,000 tonnes per year in Antarctica. Taking the combined average figures, this would equal the weight of around 125 Eiffel Towers, or around 3000 fully-laden Boeing 747s being added to the ocean each year.

Jon Hawkings added; "This is a substantial release of iron from the ice sheet, similar in size to that supplied to the oceans by atmospheric dust, another major iron source to the world's oceans.

At the moment it is just too early to estimate how much additional iron will be carried down from ice sheets into the sea. Of course, the iron release from ice sheet will be localised to the Polar Regions around the ice sheets, so the importance of glacial iron there will be significantly higher. Researchers have already noted that glacial meltwater run-off is associated with large phytoplankton blooms - this may help to explain why".

Commenting on the relevance of this study, Professor Andreas Kappler (geomicrobiologist at the University of Tubingen, Germany, who is also secretary of the European Association of Geiochemistry) said:

"This study shows that glacier meltwater can contain iron concentrations that are high enough to significantly stimulate biological productivity in oceans that otherwise are oftentimes limited in the element iron that is essential to most living organisms. Although the global importance of this flux of iron into oceans needs to be quantified and the bioavailability of the iron species found should be demonstrated experimentally in future studies, the present study provides a plausible path for nutrient supply to oceanic life."

This press release is based on the following paper: Ice sheets as a significant source of highly reactive nanoparticulate iron to the oceans. Authors Jon R. Hawkings, Jemma L. Wadham, Martyn Tranter, Rob Raiswell, Liane G. Benning, Peter J. Statham, Andrew Tedstone, Peter Nienow, Katherine Lee and Jon Telling NATURE COMMUNICATIONS | 5:3929 | DOI: 10.1038/ncomms4929, published 21 May 2014

.


Related Links
European Association of Geochemistry
Beyond the Ice Age






Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

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




Memory Foam Mattress Review
Newsletters :: SpaceDaily :: SpaceWar :: TerraDaily :: Energy Daily
XML Feeds :: Space News :: Earth News :: War News :: Solar Energy News





ICE WORLD
Hidden Greenland Canyons Mean More Sea Level Rise
Pasadena CA (JPL) May 23, 2014
Scientists at NASA and the University of California, Irvine (UCI), have found that canyons under Greenland's ocean-feeding glaciers are deeper and longer than previously thought, increasing the amount of Greenland's estimated contribution to future sea level rise. "The glaciers of Greenland are likely to retreat faster and farther inland than anticipated, and for much longer, according to ... read more


ICE WORLD
LRO View of Earth

Saturn in opposition tonight, will appear next to the moon

Russia to begin Moon colonization in 2030

Astrobotic Partners With NASA To Develop Robotic Lunar Landing Capability

ICE WORLD
Construction to Begin on NASA Mars Lander Scheduled to Launch in 2016

When fantasy becomes reality: first seeds to be planted soon on Mars

NASA's Saucer-Shaped Craft Preps for Flight Test

NASA Mars Rover Curiosity Wrapping Up Waypoint Work

ICE WORLD
Airbus design of European service module for Orion approved by ESA

Britain's Longitude Prize back after 300-year absence

Sea level rise forces US space agency to retreat

A light-speed voyage to the distant future

ICE WORLD
Moon rover Yutu comes closer to public

The Phantom Tiangong

New satellite launch center to conduct joint drill

China issues first assessment on space activities

ICE WORLD
Scientists Seek Answers With Space Station Thyroid Cancer Study

New ISS Expedition Unaffected by Proton Crash

US-Russian Tensions Roiling Outer Space Cooperation

Rounding up the BCATs on the ISS

ICE WORLD
Third-stage engine glitch causes Proton-M accident

Russia's Roscosmos plans to launch two more Protons this year

SpaceX Dragon Spacecraft Returns Critical NASA Science from ISS

SpaceX-3 Mission To Return Dragon's Share of Space Station Science

ICE WORLD
Starshade Could Help Photograph Distant Planets

Giant telescope tackles orbit and size of exoplanet

Odd planet, so far from its star

New Exomoon Hunting Technique Could Find Solar System-like Moons

ICE WORLD
New method for propulsion in fluids

MIPT Experts Reveal the Secret of Radiation Vulnerability

Physicists say they know how to turn light into matter

Russian space agency to create equipment for monitoring space debris




The content herein, unless otherwise known to be public domain, are Copyright 1995-2014 - 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. 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. Privacy Statement All images and articles appearing on Space Media Network have been edited or digitally altered in some way. Any requests to remove copyright material will be acted upon in a timely and appropriate manner. Any attempt to extort money from Space Media Network will be ignored and reported to Australian Law Enforcement Agencies as a potential case of financial fraud involving the use of a telephonic carriage device or postal service.