Featured Research

from universities, journals, and other organizations

Growing nitrous oxide levels explained

Date:
April 4, 2012
Source:
CSIRO Australia
Summary:
Scientists have generated a 65-year record of Southern Hemisphere nitrous oxide measurements, establishing a new benchmark against which to compare changes in the long-lived greenhouse gas that is also a major ozone-depleting substance.

Australia's Cape Grim Baseline Air Pollution Station, in north-west Tasmania, is a central facility in the global network of atmospheric monitoring stations and provides vital information about changes to the atmospheric composition of the Southern Hemisphere. Managed by the Bureau of Meteorology, the research program is jointly supervised by CSIRO and the Bureau.
Credit: Image courtesy of CSIRO Australia and Bureau of Meteorology

Australian, Korean and US scientists have generated a 65-year record of Southern Hemisphere nitrous oxide measurements establishing a new benchmark against which to compare changes in the long-lived greenhouse gas that is also a major ozone-depleting substance.

Published recently in the journal Nature Geoscience, the record is drawn from atmospheric sampling at the Cape Grim Baseline Air Pollution Station, Tasmania, and air extracted from the Antarctic ice sheet.

Its significance, says co-author CSIRO's Dr David Etheridge, will be its contribution to the development of emissions protocols as countries step up their monitoring of gases contributing to global warming and ozone depletion.

Nitrous oxide, N2O, is produced naturally by microbial activity in soils and the oceans as well as by agriculture. With a lifetime in the atmosphere of around 120 years, it is eventually broken down by oxidation in the stratosphere.

Scientists have measured a 20% increase in atmospheric nitrous oxide since 1750.

Dr Etheridge said that through analysis of isotopes, which are different forms of the nitrogen and oxygen comprising nitrous oxide, researchers identified that the increase of nitrous oxide was largely from agricultural sources.

"Through these measurements and a close analysis of the record we can also see seasonal cycles in N2O's isotopic composition, as well as large year-to-year variations and long-term trends," he said

He said the unique record of seasonal cycles allows scientists to trace the production and loss of nitrous oxide, from its origins in the ocean and soils to its movement through the stratosphere where it contributes to breaking down ozone.

"Until now the balance between the stratospheric sink and the oceanic source of nitrous oxide has been a key uncertainty in understanding nitrous oxide variations at Earth's surface.

"This new evidence of the budget nitrous oxide allows us to better predict its future changes- and therefore its impacts on climate and stratospheric ozone depletion -- for different scenarios of fertiliser use in support of rising populations and increased production for bio-energy," he said.

Dr Etheridge said the record demonstrates the value of Australia's investment, through CSIRO and the Bureau of Meteorology, in a world-class atmospheric monitoring station since the 1970s, with its underlying vision of establishing an air archive which can be measured as new technologies are developed.

Adding to this is the Australian Antarctic Division's glaciology program that accesses a natural archive of the past atmosphere, at its primary drilling site Law Dome.

Dr Etheridge said that better estimates of the magnitudes and geographic distribution of N2O sources and how they change over time help formulate sound emissions policies.

Led by University of California-Berkeley's Dr Sunyoung Park, Australian co-authors included CSIRO scientists at the Centre for Australian Weather and Climate Research, Drs Paul Fraser, Paul Krummel, Ray Langenfelds, Paul Steele, Cathy Trudinger, and Dr Tas van Ommen, from the Australian Antarctic Division.

The Cape Grim Air Pollution Station's scientific research is jointly managed by the Bureau of Meteorology and CSIRO Marine and Atmospheric Research. The Australian Antarctic Division and the Australian Antarctic Science Program supported access and drilling at Law Dome.

The research was supported through the Cape Grim Science Program, the Australian Climate Change Science Program and the Department of Climate Change and Energy Efficiency.


Story Source:

The above story is based on materials provided by CSIRO Australia. Note: Materials may be edited for content and length.


Journal Reference:

  1. S. Park, P. Croteau, K. A. Boering, D. M. Etheridge, D. Ferretti, P. J. Fraser, K-R. Kim, P. B. Krummel, R. L. Langenfelds, T. D. van Ommen, L. P. Steele, C. M. Trudinger. Trends and seasonal cycles in the isotopic composition of nitrous oxide since 1940. Nature Geoscience, 2012; 5 (4): 261 DOI: 10.1038/ngeo1421

Cite This Page:

CSIRO Australia. "Growing nitrous oxide levels explained." ScienceDaily. ScienceDaily, 4 April 2012. <www.sciencedaily.com/releases/2012/04/120404102941.htm>.
CSIRO Australia. (2012, April 4). Growing nitrous oxide levels explained. ScienceDaily. Retrieved September 2, 2014 from www.sciencedaily.com/releases/2012/04/120404102941.htm
CSIRO Australia. "Growing nitrous oxide levels explained." ScienceDaily. www.sciencedaily.com/releases/2012/04/120404102941.htm (accessed September 2, 2014).

Share This




More Earth & Climate News

Tuesday, September 2, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Iceland Lowers Aviation Alert on Volcano

Iceland Lowers Aviation Alert on Volcano

AFP (Sep. 1, 2014) Iceland has lowered its aviation alert on its largest volcano after a fresh eruption on a nearby lava field prompted authorities to enforce a flight ban for several hours. Duration: 01:07 Video provided by AFP
Powered by NewsLook.com
Lightning Hurts 3 on NYC Beach

Lightning Hurts 3 on NYC Beach

AP (Sep. 1, 2014) A lightning strike injured three people on a New York City beach on Sunday. The storms also delayed flights and interrupted play at the US Open tennis tournament. (Sept. 1) Video provided by AP
Powered by NewsLook.com
Thailand Totters Towards Waste Crisis

Thailand Totters Towards Waste Crisis

AFP (Sep. 1, 2014) Fears are mounting in Bangkok that poor planning and lax law enforcement are tipping Thailand towards a waste crisis. Duration: 01:21 Video provided by AFP
Powered by NewsLook.com
Melting Ice Shelves Drive Rapid Antarctic Sea Level Rise

Melting Ice Shelves Drive Rapid Antarctic Sea Level Rise

Newsy (Sep. 1, 2014) A study of almost 20 years' worth of satellite images shows Antarctic sea levels are on the rise as ice shelves continue to melt. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

More Coverage


Fertilizer Use Responsible for Increase in Nitrous Oxide in Atmosphere

Apr. 2, 2012 Chemists have analyzed the isotopic composition of nitrous oxide – a greenhouse and ozone-destroying gas - in air samples from as far back as 1940 and found the fingerprint of nitrogen-based ... read more
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins