Ozone pollution improving in the U.S.

By: Dr. Jeff Masters , 7:03 PM GMT on May 01, 2007

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Air pollution season is here, and the good news is that ozone pollution in 2006 was considerably better than in previous years. Along with pollution due to small particles (particulate matter), ground-level ozone is the most serious pollutant in the U.S. Ozone levels in 2006 showed improvement in 23 out of 35 of the major cities in the U.S. (Figure 1) compared to 2005, and was at or below the 10-year average in all but five cities. Atlanta, Georgia, showed the greatest jump in the number of unhealthy days, from 17 in 2005 to 30 days in 2006; however, this number was still below the 10-year average. Many western cities reached levels at or above the 10-year average, including San Diego, Sacramento, Denver, and Las Vegas. This was in part due to much above average summertime temperatures in the western U.S. (Figure 2). Los Angeles had the worst ozone pollution in the U.S., with 46 unhealthy days. Los Angeles also was the most polluted city overall in 2006, according to the American Lung Association. However, Los Angeles' bad ozone days declined by 16% in 2006 compared to 2005.


Figure 1. The number of days in May through September of 2005 and 2006 in which ground-level ozone reached Unhealthy for Sensitive Groups--an Air Quality Index (AQI) above 100. Corresponding 10-year averages are also shown. Image credit: EPA.

Ozone pollution has improved
Is the improvement seen in ozone levels in 2006 merely due to a lack of meteorological conditions that favor air pollution? To check, I've plotted the difference in surface temperature (degrees C) from May-September 2006, compared to the 10-year average from 1995-2005 (Figure 2). The chemical reactions that form ozone are most efficient at high temperatures, so if the summer of 2006 was cooler than usual, we'd expect a drop in ozone levels. However, the summer of 2006 was the second warmest in U.S. history--but ozone levels still dropped. All of the cities where ozone increased significantly in 2006 over 2005 levels were areas where temperatures were above average. Los Angeles had summer temperatures more than 1 degree C above normal, yet still recorded a drop in ozone, suggesting that strategies to control ozone pollution there are paying dividends. In fact, new rules to limit nitrogen oxide emissions from power plants have been enacted nation-wide in the past few years, and the ozone pollution statistics from 2006 are evidence that these emissions rules are working. Ozone pollution since 1980 has dropped 21% (Figure 3), despite the fact that the average summer temperatures have generally been increasing.


Figure 2. The difference in surface temperature (degrees C) from May-September 2006, compared to the 10-year average from 1995-2005. Temperatures were above the 10-year average across most of the country, except for New Mexico, and portions of the Ohio Valley surrounding Kentucky. Image credit: NCAR/NCEP.


Figure 3. Trends in ozone air pollution in the U.S. (white line) and uncertainty (blue areas, marking the standard deviation). The federal standard of 0.08 ppm is indicated by the dashed line. Since 1980, maximum ozone levels have declined 21%. Since 1990, the decline has been 9%. Note that the lowest ozone levels were recorded in 2004, which was an exceptionally cool summer across most of the U.S. Image credit: U.S. EPA.

Next blog (Thursday): Pollution costs and deaths exceed the impact of a new Hurricane Katrina hitting the U.S. each year.

Jeff Masters

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488. kmanislander
2:37 AM GMT on May 03, 2007


Here is one of those planes that crash landed some time ago
Member Since: August 19, 2006 Posts: 0 Comments: 15842
487. kmanislander
2:30 AM GMT on May 03, 2007
pottery

do you have wild fires there ?
We had one here two weeks ago that was threatening the National Botanic Park but because the fire was beyond any access road they water bombed it using the mosquito spray plane !

King of funny after the fact, seeing a little plane dropping about 200 gallons at a time but it did the trick LOL
Member Since: August 19, 2006 Posts: 0 Comments: 15842
486. pottery
10:25 PM AST on May 02, 2007
Hi Kman. Still hot hot hot.... The place is on fire too, and a lot of the central part of the Island is clay. We are turning it into ceramic fast. Ever try to grow anything on a ceramic tile ? Its sad to see that no effort is being made to stop the burning............
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485. pottery
10:20 PM AST on May 02, 2007
Yeah Moonlight, the ceiling fans are struggling to keep up. But more than A/C units, I'm trying to find water. Rainfall figures from Nov. to date are WAY off, and the resevoirs are getting low. Bought another 1600 gal truckload today. Its costing.......
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484. kmanislander
2:23 AM GMT on May 03, 2007
hi pottery

Still hot down S eh ??
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482. Tazmanian
7:18 PM PDT on May 02, 2007
moonlightcowboy not sure yet


by the way this is so cool tell me what you think i love it i been wanting to see some in like this for a long time now

no need to down lode any more if you dont want to

Link
Member Since: May 21, 2006 Posts: 5091 Comments: 115239
481. moonlightcowboy
2:17 AM GMT on May 03, 2007
Hey, "pottery" ....good to see you, too! Find some A/C!!!!
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480. pottery
10:13 PM AST on May 02, 2007
Hi there, all. The local Met. Office has confirmed rhat April was the hottest April in history here in Trinidad. Your'e telling me ! Whew....
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479. Bamatracker
2:03 AM GMT on May 03, 2007
sorry man...just thought i would ask because of that line up moonlight posted...lOL
Member Since: May 17, 2006 Posts: 6 Comments: 1367
478. moonlightcowboy
2:02 AM GMT on May 03, 2007
Hey, Taz...of course, we know your prognosticating is really tall!!! How's this season gonna shape up the way you see it now?
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477. Tazmanian
7:01 PM PDT on May 02, 2007
Posted By: Bamatracker at 6:58 PM PDT on May 02, 2007.

hey taz...your only 3 feet tall?


lol thats too funny
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476. Bamatracker
1:57 AM GMT on May 03, 2007
hey taz...your only 3 feet tall?
Member Since: May 17, 2006 Posts: 6 Comments: 1367
475. Tazmanian
6:51 PM PDT on May 02, 2007
moonlightcowboy well said lol welcome back
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474. Bamatracker
1:44 AM GMT on May 03, 2007
aahhh...thanks for clearing that up moonlight. Just wondering what he meant cuz i didnt understand.
Member Since: May 17, 2006 Posts: 6 Comments: 1367
473. moonlightcowboy
1:39 AM GMT on May 03, 2007
bigfoot-size-1.jpg

...that's "Taz speake"...and he's one of the best on the board...sometimes, I don't quite understand some of the things he says, but heck, I'm not that smart; but, I do enjoy reading the "speake." He's a great guy and follows the storms avidly and mostly smartly.
Of course, Taz, understands the "smell factor"...lol.

By "it's June"...I think he means, it's good to see folks back on here, too, getting ready for the season...lol. Much respect, TAZ.

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472. Tazmanian
6:39 PM PDT on May 02, 2007
Posted By: Bamatracker at 6:36 PM PDT on May 02, 2007.

Taz say what?

Posted By: Tazmanian at 6:35 PM PDT on May 02, 2007.

its june lol


Bamatracker i said its june but i am this kiding
Member Since: May 21, 2006 Posts: 5091 Comments: 115239
471. crackerlogic
1:39 AM GMT on May 03, 2007
6-10 foot are big waves, we didn't even get them that big during wilma
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470. Bamatracker
1:35 AM GMT on May 03, 2007
Taz say what?
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469. Tazmanian
6:32 PM PDT on May 02, 2007
its june lol
Member Since: May 21, 2006 Posts: 5091 Comments: 115239
468. crackerlogic
1:31 AM GMT on May 03, 2007
sweet, my wave forcast show some waves in the gulf mon and tue next week, and i have no clue where they are getting the info
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467. Bamatracker
1:30 AM GMT on May 03, 2007
cracker....ill say june 13th there should be some 6-10 ft waves for ya!
Member Since: May 17, 2006 Posts: 6 Comments: 1367
466. kmanislander
1:30 AM GMT on May 03, 2007
wow where the heck did that pic come from
I just tried to remove it and the edit did not take
Any suggestions. Didn't mean to blow the margins. Sorry
Member Since: August 19, 2006 Posts: 0 Comments: 15842
465. crackerlogic
1:26 AM GMT on May 03, 2007
are you guys still talking about "the first wave"? I thought we went over this? All i want to know is when can i go surfing on the west side of Florida
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464. Bamatracker
1:29 AM GMT on May 03, 2007
aaaaaaaaaaaahhhhhhhhh!!! blog is stretched. booooooooooooo!!!
Member Since: May 17, 2006 Posts: 6 Comments: 1367
463. Bamatracker
1:28 AM GMT on May 03, 2007
ohhh...ok...good movie!!
Member Since: May 17, 2006 Posts: 6 Comments: 1367
461. Baybuddy
1:20 AM GMT on May 03, 2007
No Bama, I am afraid that was supposed to have been from Willie Wonka. The scene in the boat on the chocolate river.
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460. kmanislander
1:20 AM GMT on May 03, 2007
hope this works
Member Since: August 19, 2006 Posts: 0 Comments: 15842
459. moonlightcowboy
1:16 AM GMT on May 03, 2007
eyestoplogo1left.jpg

Don't forget the "smell factor" this season. This new aspect in forecasting was only recognized in 2006 (unofficially); but, lended merit to prognosticating and became an intriguing, light blog enhancement (maybe, at least occasionally to some...lol).

More to come soon on the "smell factor" and what it means to land-falling storms. For those of you whom endured the relentless wishcasting, blatent blogging and arguing, hopefully the prospects of this addition to following the storms in 07, will add some relavent discussion and keep things in perspective.

Yep, it's getting close. It's good to see, some of the names again...23, SJ, Patrap, kman, TAZ, and so many others, too. There are many, very smart people here that offer really smart thought and analysis. Sure, there's a few (self???) that sometimes cloud the issues. But, I always enjoy being here, learning, participating. It's a great site and I plan on learning as much as I can and asking questions. For the "newbies"...I encourage that kind of patience...ask questions, learn, have fun, participate...and of course, most of all, be smart and safe.

Hopefully, the "smell factor" will enlighten a few, too.

...."reasoning with the season"....hopefully, this season will be "light" on all of us!!!

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458. Bamatracker
1:18 AM GMT on May 03, 2007
so let me get this straight...magic is keeping the big waves off africa from actually forming by poofing them and making them fizzle?
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457. kmanislander
1:17 AM GMT on May 03, 2007
the blog is hopping tonight
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456. Bamatracker
1:16 AM GMT on May 03, 2007
baybuddy....are you a rapper?
Member Since: May 17, 2006 Posts: 6 Comments: 1367
455. kmanislander
1:13 AM GMT on May 03, 2007
these pre season waves are of interest but it remains to be seen if they continue that strong once the Cape Verde season begins in late July. I have seen many that look like that come off in July and just fizzle out ( another technical term Bama LMAO )
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454. Bamatracker
1:15 AM GMT on May 03, 2007
oooooohhhh...i like magic
Member Since: May 17, 2006 Posts: 6 Comments: 1367
453. Baybuddy
1:15 AM GMT on May 03, 2007
I guess there's just no way of knowing... Which direction we are flowing... Is it raining?... Is it snowing?... Is a Hurricane A Blowing?... YES!... THE DANGER MUST BE GROWING! BECAUSE THE ROWERS KEEP ON ROWING! AND THEY ARE NOT SHOWING ANY SIGNS THAT THEY ARE SLOWING! Quite right sir, STOP THE BOAT!
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452. franck
1:14 AM GMT on May 03, 2007
Hellsniper223...absolutely.
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451. chessrascal
1:12 AM GMT on May 03, 2007
Patrap that was a good video but i dont think it gives the real picture. I mean look at Jeff Masters "flying into hurricane Hugo" I think that gives the real picture.
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450. kmanislander
1:12 AM GMT on May 03, 2007
very technical LOL
as in magic !
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449. chessrascal
1:10 AM GMT on May 03, 2007
i agree Kman but i think its impressive that its producing waves like that this early.
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448. Bamatracker
1:11 AM GMT on May 03, 2007
kman is "poof" one of those there technological terms?
Member Since: May 17, 2006 Posts: 6 Comments: 1367
447. kmanislander
1:07 AM GMT on May 03, 2007
chessrascal
3 months from now and 5 degrees further N and we would be paying REAL CLOSE attention to that cluster of TStorms.
For now, they will go "poof" as soon as they hit water
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446. Hellsniper223
1:07 AM GMT on May 03, 2007
I hate to be a naysayer 'bout them there tropical waves, but... 9 out of 10 systems that move off of Africa this time of year loose pretty much all of their convection once they've been in the water for more than 8 hours.
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445. chessrascal
1:07 AM GMT on May 03, 2007
http://www.wunderground.com/radar/radblast.asp?ID=DFX&showstorms=10
vortex signature
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444. franck
12:59 AM GMT on May 03, 2007
Patrap..that was very informative and entertaining. Think I should watch it with the audio?
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443. Bamatracker
1:03 AM GMT on May 03, 2007
the storm in texas is interesting in how it expands to cover more area as it moves to the east.
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442. chessrascal
1:01 AM GMT on May 03, 2007
lol

look at that wave about to come off of Africa!
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441. kmanislander
1:02 AM GMT on May 03, 2007
good evening all
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440. StormJunkie
1:03 AM GMT on May 03, 2007
Good lookin out 23! :~)
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439. hurricane23
9:02 PM EDT on May 02, 2007
Seems to be weaking in intensity...
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438. Patrap
8:01 PM CDT on May 02, 2007
Dealy Plaza Webcam..live. Link
Member Since: July 3, 2005 Posts: 426 Comments: 128657

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Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.