Bookmark Kaumudi Online  Bookmark this site  Editor@Kaumudi  |  Marketing  Print Advt rates  |  Calendar 2018        Go!    
 
 
July 19, Thursday 2018 1:38 AM       

       HEADLINES: Bihari woman found hanging in seminary                                              New assignment for ADGP Sudhesh Kumar                                              PC George turns violent at Paliyekkara toll plaza, toll barrier destructed                                              I pulled down barrier...civil rights can be protected this way only: P C George                                              Abhimanyu murder: Main accused Muhammad arrested                                              Dogs who sniffed out Bin Laden to help CISF                                              Reham Khan’s autobiography mentions Shah Rukh Khan                                              PM ready for any discussion as monsoon session of parliament begins                                              6 held for 'sexually assaulting' Russian tourist in TN                                              MiG 21 crashes in Kangra district of Himachal                                              Google fined 5 billion dollars by EU                                              Root and Morgan clinch decider for England in ODI series                                              Kaumudi Facebook
       SCI&TECH Next Article: Google Assistant helps you set music alarms  
       Scientists discover enormous reserves of mercury in permafrost
 
         Posted on :18:09:07 Feb 7, 2018
   
A A
       Last edited on:18:09:07 Feb 7, 2018
         Tags: Scientists discover enormous reserves of merc
 

WASHINGTON DC: Scientists have discovered massive reserves of mercury hidden in permafrost.

Permafrost is a thick subsurface layer of soil that remains below freezing point throughout the year, occurring chiefly in polar regions.

Researchers have discovered permafrost in the northern hemisphere stores massive amounts of natural mercury, a finding with significant implications for human health and ecosystems worldwide as exposure to mercury - even small amounts - can cause serious health problems.

The study reveals the northern permafrost soils are the largest reservoir of mercury on the planet, storing nearly twice as much mercury as all other soils, the ocean and the atmosphere combined.

In a new study, scientists measured mercury concentrations in permafrost cores from Alaska and estimated how much mercury has been trapped in permafrost north of the equator since the last Ice Age.

"This discovery is a game-changer," said Paul Schuster, a hydrologist at the US Geological Survey in Boulder, Colorado and lead author of the new study. "We've quantified a pool of mercury that had not been done previously, and the results have profound implications for better understanding the global mercury cycle."

Warmer air temperatures due to climate change could thaw much of the existing permafrost layer in the northern hemisphere. This thawing permafrost could release a large amount of mercury that could potentially affect ecosystems around the world. Mercury accumulates in aquatic and terrestrial food chains, and has harmful neurological and reproductive effects on animals.

"There would be no environmental problem if everything remained frozen, but we know the Earth is getting warmer," Schuster said. "Although measurement of the rate of permafrost thaw was not part of this study, the thawing permafrost provides a potential for mercury to be released--that's just physics."

The new findings have major implications for understanding how Earth stores mercury and for human and environmental health, according to James Shanley, a research hydrologist at the U S Geological Survey in Montpelier, Vermont, who was not involved with the new research.

"This study is very novel and makes a big discovery in an area that was previously somewhat ignored," Shanley said. "It shows permafrost represents a huge source of mercury, and if it thaws due to climate change the mercury could be released and could significantly add to the global mercury burden."

Natural mercury found in the atmosphere binds with organic material in the soil, gets buried by sediment, and becomes frozen into permafrost, where it remains trapped for thousands of years unless liberated by changes such as permafrost thaw.

Schuster's team determined the total amount of mercury locked up in permafrost using field data. Between 2004 and 2012, the study authors drilled 13 permafrost soil cores from various sites in Alaska, and measured the total amounts of mercury and carbon in each core. They selected sites with a diverse array of soil characteristics to best represent permafrost found around the entire northern hemisphere.

Schuster and his colleagues found their measurements were consistent with published data on mercury in non-permafrost and permafrost soils from thousands of other sites worldwide. They then used their observed values to calculate the total amount of mercury stored in permafrost in the northern hemisphere and create a map of mercury concentrations in the region.

The study found approximately 793 gigagrams, or more than 15 million gallons, of mercury is frozen in northern permafrost soil. That is roughly 10 times the amount of all human-caused mercury emissions over the last 30 years, based on emissions estimates from 2016.

The study also found all frozen and unfrozen soil in northern permafrost regions contains a combined 1,656 gigagrams of mercury, making it the largest known reservoir of mercury on the planet. This pool houses nearly twice as much mercury as soils outside of the northern permafrost region, the ocean and the atmosphere combined.

Scientists are still unsure how much of the stored mercury would affect ecosystems if the permafrost were to thaw. One major question revolves around how much of the mercury would leach out of the soil into surrounding waterways, according to Steve Sebestyen, a research hydrologist at the USDA Forest Service in Grand Rapids, Minnesota, who was not involved with the new research.

If the mercury is transported across waterways, it could be taken up by microorganisms and transformed into methylmercury, he said. This form of mercury is a dangerous toxin that causes neurological effects in animals ranging from motor impairment to birth defects.

"There's a significant social and human health aspect to this study," Sebestyen said. "The consequences of this mercury being released into the environment are potentially huge because mercury has health effects on organisms and can travel up the food chain, adversely affecting native and other communities."

Edda Mutter, science director for the Yukon River Inter-Tribal Watershed Council, said the new study demonstrates thawing permafrost could have grave consequences for local ecosystems and indigenous communities in the northern hemisphere.

"Rural communities in Alaska and other northern areas have a subsistence lifestyle, making them vulnerable to methylmercury contaminating their food supply," Mutter said. "Food sources are important to the spiritual and cultural health of the natives, so this study has major health and economic implications for this region of the world."

The release of mercury could also have far-reaching global consequences, according to Shanley. Mercury released into the atmosphere can travel large distances and could affect communities and ecosystems thousands of miles away from the release site, he said.

Schuster believes his team's research gives policymakers and scientists new numbers to work with and calibrate their models as they begin to study this new phenomenon in more detail.

"24 per cent of all the soil above the equator is permafrost, and it has this huge pool of locked-up mercury," he said. "What happens if the permafrost thaws? How far will the mercury travel up the food chain? These are big-picture questions that we need to answer."

The new study was published in Geophysical Research Letters, a journal of the American Geophysical Union.

A A
       SCI&TECH
Next Article: Google Assistant helps you set music alarms
 
 
SCI&TECH HEADLINES
Yoga helps against non-communicable diseases: WHO  
Spironolactone can help prevent acne: Study  
Older Amazonian forests help regulate global climate  
Goal conflict linked to depressive symptoms  
A new world: Top 10 new species for 2018  
Beat the risk of frailty with healthy heart  
Twitter to hide trolls that hurl abuse: Twitter CEO  
Fortnite is finally coming to Android  
This test could detect signs of pancreatic cancer  
Aliens exist but may be in parallel Universe: Study  
This is your heart on nitric oxide  
Is your kid's heart clock ticking right?  
Do at-risk adolescents show depressive symptoms on social media?  
NASA launches Insight spacecraft to Mars for deepest dig yet  
Daily intake of this drug can cause certain cancers in men  
A new weapon against epilepsy  
Hail stone weighing three kg sign of climate change: Expert  
PMSing? Could be because of alcohol!  
Social media firms given a week to better protect kids  
The stronger you are, the healthier your brain is  
NASA may soon identify 2,400 alien planets  
What triggers depression among adults?  
Turn your hobbies into part-time job opportunities with these apps  
Apple launches special RED Edition for iPhone 8, 8 Plus  
Humanity’s first flight to Sun to launch in July: NASA  
 
Do you support Kottayam collector's warning against selfies at water-logged places?
yes
 
no
 
no opinion
 
 
 
Home Kerala India World Business Sports Sci&Tech Education Automobile CityNews Movies Environment Letters 
© Copyright keralakaumudi Online 2011  |  Reproduction in whole or in part without written permission is prohibited.
Head Office Address: Kaumudi Buildings, Pettah P.O, Trivandrum - 695024, India.
Online queries talk to Deepu Sasidharan, + 91 98472 38959 or Email deepu[at]kaumudi.com
Customer Service -Advertisement Disclaimer Statement   |  Copyright Policy