NOAA Study Shows Nitrous Oxide Now Top Ozone-Depleting Emission

[cletus8269]

(if this fits another section better feel free to move it there.)

Nitrous oxide has now become the largest ozone-depleting substance emitted through human activities, and is expected to remain the largest throughout the 21st century, NOAA scientists say in a new study.

For the first time, this study has evaluated nitrous oxide emissions from human activities in terms of their potential impact on Earth’s ozone layer. As chlorofluorocarbons (CFCs), which have been phased out by international agreement, ebb in the atmosphere, nitrous oxide will remain a significant ozone-destroyer, the study found. Today, nitrous oxide emissions from human activities are more than twice as high as the next leading ozone-depleting gas.

Nitrous oxide is emitted from natural sources and as a byproduct of agricultural fertilization and other industrial processes. Calculating the effect on the ozone layer now and in the future, NOAA researchers found that emissions of nitrous oxide from human activities erode the ozone layer and will continue to do so for many decades.

The study, authored by A.R. Ravishankara, J.S. Daniel and Robert W. Portmann of NOAA's Earth System Research Laboratory (ESRL) chemical sciences division, appears online today in the journal Science. ESRL tracks the thickness of the ozone layer, as well as the burden of ozone-depleting compounds in the atmosphere. It maintains a large portion of the world air sampling and measurement network. NOAA scientists also conduct fundamental studies of the atmosphere and atmospheric processes to improve understanding of ozone depletion and of the potential for recovery the ozone layer.

“The dramatic reduction in CFCs over the last 20 years is an environmental success story. But manmade nitrous oxide is now the elephant in the room among ozone-depleting substances,” said Ravishankara, lead author of the study and director of the ESRL Chemical Sciences Division in Boulder, Colo.

The ozone layer serves to shield plants, animals and people from excessive ultraviolet light from the sun. Thinning of the ozone layer allows more ultraviolet light to reach the Earth’s surface where it can damage crops and aquatic life and harm human health.

Though the role of nitrous oxide in ozone depletion has been known for several decades, the new study is the first to explicitly calculate that role using the same measures that have been applied to CFCs, halons and other chlorine- and bromine-containing ozone-depleting substances.

With CFCs and certain other ozone-depleting gases coming in check as a result of the 1987 Montreal Protocol, the international treaty that phased out ozone-destroying compounds, manmade nitrous oxide is becoming an increasingly larger fraction of the emissions of ozone-depleting substances. Nitrous oxide is not regulated by the Montreal Protocol.

Nitrous oxide is also a greenhouse gas, so reducing its emission from manmade sources would be good for both the ozone layer and climate, the scientists said.

In addition to soil fertilization, nitrous oxide is emitted from livestock manure, sewage treatment, combustion and certain other industrial processes. Dentists use it as a sedative (so-called “laughing gas”). In nature, bacteria in soil and the oceans break down nitrogen-containing compounds, releasing nitrous oxide. About one-third of global nitrous oxide emissions are from human activities. Nitrous oxide, like CFCs, is stable when emitted at ground level, but breaks down when it reaches the stratosphere to form other gases, called nitrogen oxides, that trigger ozone-destroying reactions.

NOAA understands and predicts changes in the Earth's environment, from the depths of the ocean to the surface of the sun, and conserves and manages our coastal and marine resources.

http://www.noaanews.noaa.gov/stories2009/20090827_ozone.html

[ZL-1]

Errrr.............. ozone layer depletion is a crock of $h!?

[Justin Bimmer]

I LOVE IT! I am laughing my ass off out here in California. All the air boards (ones who regulate pollution) except the ones in the SF bay area have forced cities to switch from low NOx emitting diesel buses to high NOx emitting CNG buses.

Now that diesel is super clean and much more efficient, they are all going to look like dopes.

They should have listened to us.

[pow]

I LOVE IT! I am laughing my ass off out here in California. All the air boards (ones who regulate pollution) except the ones in the SF bay area have forced cities to switch from low NOx emitting diesel buses to high NOx emitting CNG buses.

Now that diesel is super clean and much more efficient, they are all going to look like dopes.

They should have listened to us.

CNG reduces both PM and NOx pollution compared to diesel...

[SAmadei]

So does this mean that the government will be funding projects to extract and bottle NOx from the atmosphere? Then it can be sold to the hot rodders!

[ShadowDog]

So does this mean that the government will be funding projects to extract and bottle NOx from the atmosphere? Then it can be sold to the hot rodders!

It would be easier for the government to ban the use of NOx altogether.

Oh Noes! Now, all the rice-burners will be left with is stock hamster power?! Perish the thought! Meh, I never really cared for 'bottle' fueled cars.

[Justin Bimmer]

Current DOE projections show at most a 17% reduction in NOx from clean diesel technology currently in use.

But, CNG gets you 1/2 the efficiency as diesel does.

[cletus8269]

It would be easier for the government to ban the use of NOx altogether.

Oh Noes! Now, all the rice-burners will be left with is stock hamster power?! Perish the thought! Meh, I never really cared for 'bottle' fueled cars.

watched an episode of american muscle car from the final season about forced induction. gale banks was doing most of the talking like he knew what he was talking about () saying nitrous is fun for a while and may be good for the strip but is by no means a reliable source of power like SC or TC.

[balthazar]

>>" In nature, bacteria in soil and the oceans break down nitrogen-containing compounds, releasing nitrous oxide. About one-third of global nitrous oxide emissions are from human activities. "<<

Let me get this straight: ALL of the land masses & ALL of the oceans of Earth release nitrous oxide, yet man --with his dental laughing gas and environmentally-unfriendly sewage treatment-- is releasing 1/3 of the world's output ????

I love these pronouncments that are utterly impossible to prove or disprove.

[loki]

NOAA understands and predicts changes in the Earth's environment, from the depths of the ocean to the surface of the sun, and conserves and manages our coastal and marine resources.

if they understand it and can predict, i want them as my forcasters. what's it gonna be like here on dec 21 2012? LOL

what an ignorant statement.