The east coast was cloudy today and portions of the west were covered in smoke from various fires, including a long plume over the northwest. (Note that the western image below is from MODIS Aqua and the eastern image is from MODIS Terra).
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The western smoke plume is clearly visible in the MODIS AOD data from the IDEA site.
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The NOAA GASP AOD beautifully captures the long plume of smoke in the western U.S.
The EPA AirNow site revealed low concentrations of PM2.5 across most of the U.S. There are few PM monitors in the west and the smoke is likely high in the atmosphere, so it would not be indicated in this image.
Today's GASP AOD animation shows mostly cloudy skies in the Northeast. Elevated AOD values are still located in the far North, which is most likely related to the smoke from the AK/CA fires. We have included a “Cloud Fraction” on each frame of the movie. This is the ratio of the number of masked pixels to the total number of pixels in each frame. The assignment to clouds assumes that all of the masked pixels are due to clouds, which is for the most part true for the times shown and for the Eastern U.S. The cloud fraction should be taken as an indication, rather than a high precision result.
Today's INTEX (DC-8) flight was scheduled to be over parts of the Atlantic. MODIS RGB images sourced from Rapidfire have been posted to help facilitate the INTEX research. Cloudy conditions and sun glint are apparent.
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AOD images were also sourced to help INTEX scientists with their research. The IDEA AOD product shows mostly cloudy skies in the Northeast and the NOAA ?NESDIS GASP map shows relatively the same thing.
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Today's particle pollution (PM2.5) map sourced from EPA AIRNow shows mostly moderate conditions in the East and West.

Below are MODIS RGB images which shows smoke from Canada moving into the Northwest U.S. Rapidfire provides a clear view: Click here for Rapidfire image
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Today was cloudy, with the cloud layer staying around 0.75 km from the start of the run to 1545z. After 1545z there was a significant decrease in aerosol concentration below the cloud base, which rose to 1.25 km by 1900z.
This true color picture shows a cloudy eastern U.S. with Maryland being partially covered. The AOD is moderate. Please see AOD maps of Great Lakes region and southeast .
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This is a GASP image showing Aerosol Optical Depth over the US. The northwest has elevated AOD.
Concerning the PM2.5 particle concentration, some sites in the east and northeast were under code yellow. Three sites in California had an "unhealthy" air quality. The rest of the country had a relatively good air quality. (Source:EPA Airnow)
This morning started with several stratified layers up to 1.5 km, one of which developing into a clouds by 1600z. There was also the usual development of the daytime boundary layer, however at 1900z there was a large drop in aerosol concentration in the boundary layer.
The Columbia River Gorge webcam showed low visibility today.
(Compare to a clear day).
Washington State still has elevated AOD as well as northern California. Some fires in the west are also producing smoke plumes.
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Today was a mixture of clouds between 2 km and 3 km and moderate haze below 1 km, which was occasionally topped by clouds.
Smoke is still present in the far Northwest and Northeast. The Extension of the Northeastern smoke plume is clearly seen in this MODIS Rapidfire image. Several fires are present in the Southeast. One Georgia fire in particular is easily distinguishable in a MODIS RGB(Source:UW) image.
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IDEA shows the smoke plumes in the Northeast and Northwest.
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Here is the NOAA NESDIS GASP map for 19:45UTC.

Today's particle pollution (PM2.5) map sourced from EPA AIRNow shows mostly “good”(green dots) to “moderate” (yellow dots)” AQI. California had a single incidence of unhealthy AQI. Moderate conditions in Washington State are likely related to the smoke in the area.

As a former resident of eastern Washington, I was interested to see how the smoke was affecting their air quality. The Columbia River Gorge webcam has low visibility.
Here is what the Gorge looks like on a clear day.
Spokane County Air Pollution Authority is reporting 37 ug/m3 PM2.5 this afternoon and rising.
The smoke coming from Canada is visible in these MODIS true color pictures. The plume is entering the US near the Great Lakes region and is slowly moving eastward. Maryland is under a very cloudy sky. (source: UW MODIS Direct & /NASA/EPA/NOAA/UW IDEA )
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The same plume is visible on this GASP image. As Nikisa mentioned yesterday, another plume is entering the U.S. by the northwest above the state of Washington.( See band 02,07,07 image)
Concerning the Air Quality Index, central California, which often has a high AQI, is under code orange. Some sites under code yellow are scattered in the northwest and the east. The northeast has a relatively good air quality.
This HMS map shows a smoke plume over Washington as well as plumes in the northeast of the country and southern Texas.
Smoke continues to move into the Northwest (over Washington State) and North Central U.S.; new Canadian fires are most likely contributing to this event. Skies were mostly cloudy in the East and hazy conditions were still present in the Southeast. The source of the Southeastern haze is still unknown, however local fires may be responsible.
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The IDEA and GASP images below show elevated AOD in the Northwest, Northeast, and North Central U.S.
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NRL's NAAPS Global Aerosol Model (shows smoke) for North America -Current.

AQI is mostly moderate in regions where haze and smoke are persistent. View EPA's PM2.5 map below.

Today was a mixture of haze and low clouds. Near the surface, there was a high amount of aerosols that were vertically well mixed around 1800z. The aerosol concentration sharply dropped off after 1830z.
We have not seen the Sun in several days now. At least today looks to be partly cloudy. At present, the UMBC LIDAR systems show thin clouds at 800m with a heavy, broken cloud deck at 3.2km.
Haze/smoke/dust(?) continued in the deep south and the Gulf of Mexico today as well as a stream of smoke in Canada, dipping just north of the Great Lakes.
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Note how the stream of smoke seems to be related to the cloud formation in this MODIS image of Canada.
The haze in the south and near the Great Lakes was also visible as high AOD in the MODIS AOD images from the IDEA site.
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The NOAA GASP AOD also showed the smoke and haze.
The EPA AirNow site revealed moderate concentrations of PM2.5 across the south. Note also that southern California has high values but the satellite image did not show any haze, so it is likely localized.
I added a new link to the National Center for Atmospheric Research (NCAR) Real-Time Weather, a weather site with in-depth information, including geostationary satellite images, radar, upper air and surface data.
The EPA AirNow site returned to operation. Here are the average concentrations for July 24. The haze in the south produced several 'Unhealthy' readings.
Florida and parts of the deep south continued to still be covered in haze, likely a mix of well-travelled Alaskan smoke, local haze, and a little Saharan dust. (Note that the bright area near Louisiana is sunglint.) As Kamonayi predicted, some light smoke can also be seen entering the north central U.S.
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The haze in the south and the new incoming smoke was also visible as high AOD in the MODIS AOD images from the IDEA site.
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The NOAA GASP AOD also showed the haze over the south but did not capture the north central smoke very clearly.
The EPA AirNow site was not producing data today.
The smoke plume coming from Canada is pushed a little bit further east compared to yesterday data. Now, it is almost completely out of the continent. The plume extends from the north to the Midwest . It is very cloudy and hazy in Maryland.
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This GASP image shows regions with high AOD near Arkansas and also, east and west of Florida. Central and northeastern U.S. are very cloudy and hazy.
Three sites have declared a code red: one in California, Maine and Massachusetts. Most of the sites in the northeast are under code orange. Maryland has an AQ considered “moderate”. Green regions have a “good” Air Quality Index with “no health impact (…) expected” .
This GASP animation shows the smoke plume segmented in three parts: one above Maine, another one close to New York and the last one near Florida.
There still are some fires in Florida which could perhaps be producing a smoke plume possibly being masked by the remaining of the Alaska and British Columbia smoke. Fires are still burning in Alaska producing a large quantity of smoke. Also, this HMS map shows some plumes in northern California as well as in Washington. Notice that another smoke plume from Canada is entering the U.S., once again, near the state of North Dakota. Stay tuned to see how it will evolve.

As you can see by the absence of GASP data due to the cloud mask in the following image, much of the northeast is clouded over. The forecast for Baltimore today calls for clouds, rain, and scattered T-storms. So, we will probably not be running the UMBC lidars today.
On this MODIS true color image, the east coast is covered by clouds, haze and a smoke plume extending from the north to southern Florida. Its AOD averages 0.8. Central U.S. is cloudy and hazy.
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On this GASP image, the smoke plume can be seen in a yellow-green color extending from the northeast to northern Texas passing above Florida. The sky in Maryland is cloudy and hazy.
On today's AQI map, most of the eastern sites and some scattered sites in California are under code yellow. Central California and the state of New York both have a site under code red. Orange regions have an AQI said to be "unhealthy for sensitive groups".
On this GASP animation, the plume is slightly transported to the East.

There is one visible remaining fire in California. There are several scattered fires in southern and central U.S. (source: MODIS Rapidfire)
The high humidity mixed with aerosols has produced a very heavy layer with AOD ~ 0.5 for much of the day. There is also a relatively thin cloud layer between 1 and 3km later in the day.
GASP shows very high AOD along the Eastern Seaboard. Here in Baltimore it is very hazy with limited visibility.
We would also like to welcome the newest REALM member, Ed Eloranta and his lidar group at the University of Wisconcin Space Science and Engineering Center (SSEC/UW). You can check their website at http://www.ssec.wisc.edu/
The forecast promices a hot/humid day in Baltimore today. As you can see in this view from Ray Hoff's office, there is substantial haze (that's the Sun to the upper right.) Downtown Baltimore is not visible.
MODIS RapidFire website has MODIS Terra images showing some fires in the south and northeast.
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Hazy and smoke filled skies are still evident in the Northeast. The smoke is beginning to move off land towards the Atlantic. Smokey and hazy conditions were also apparent in the South.
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The smoke is also clearly seen in the IDEA AOD images.
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Northeastern GASP animation shows the smoke headed for the Atlantic.

Please check out the NOAA NESDIS GASP loop for the entire nation.
EPA AIRNow shows mostly moderate conditions around the nation. Very unhealthy (purple dot) conditions still remain in California.

We saw what appeared to be the remnants of the Yukon smoke plume early today. The plume dissipated as it moved out of area toward the east as seen in the GASP movie posted today.
The UMBC lidar shows that some of the Yukon smoke plume is still with us. As you can see, there is a layer at about 1km that is mixing downward. It will be interesting to see if this is detectable on the ground.
Today's early GASP images show that the Yukon smoke plume is still intact. Here in Baltimore we are just on the edge with slightly elevated optical depths. There is some evidence of the plume in today's lidar returns as well.
It looks like we are off to a hazy start. Is smoke still around? Stay linked to the blog for Dr. McCann's Lidar post.
Image taken @ 7:30am
We showed several sets of results earlier today as we followed the progress of the Yukon plume; here we present the complete run of two laser systems in the UMBC Lidar Laboratory. The following two figures show the lidar returns for two different wavelengths. The first is for a green laser (532nm), which is the laser we most often record on this blog. The second plot shows a similar time series for the elastic channel of our ultraviolet laser (355nm). The color scales have been chosen to give the same color to the returns from white clouds. As you can see the results are similar in many ways, but there are also differences in the backscatter (reflectance) for the aerosols, and in the structure shown.
The smoke plume between 1 and 2km is evident early in the day for both systems. There is a structure that comes in late in the day and descends from about 6km to 4km, and is especially evident in the UV returns. This could be more of the smoke from the Yukon. By the end of the day, the original 1-2km smoke plume has merged with the BL and is masked by the clouds; so that it is not easily distinguished.
As seen in these MODIS Terra images, the smoke coming from Canada covers the whole eastern U.S. all the way south into Texas. The MODIS Aerosol Optical Depth images are taken from the IDEA website where images of Great Lakes region are also available.
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On this GASP image, the plume extends from the North all the way down to the south. It is not as clear as in yesterday post and has significantly moved eastward.
Most of the sites in central and eastern U.S. and some sites in south California are under code yellow or "moderate" air quality. The Central California region is under code purple which is the poorest air quality. The northeast has an AQ said “good”.
Longer Gasp AOD animation for the North East.
Note that some fires are burning in central U.S. and the east coast (see previous post).
MODIS RapidFire has MODIS Terra images showing some fires in California and the northwest The Fires are represented by red dots. Some fires are burning in central U.S. and on the east coast .
The usual midday cloud build-up has obscured the smoke plume for the most part. The plume is still occasionally visible between the clouds, but appears to be thinning. The GASP data indicates that the plume continues to move towards the SE.
Below is the current GASP AOD animation, which shows smoke in the Northeast.
The smoke from the Yukon fires that we have been tracking for several days now has reached Baltimore. The haze from the smoke is visually apparent. The UMBC Elastic Lidar Facility image below shows the aerosol cloud aloft in a band between 1 and 2 km.
The early images from GASP (NOAA/NESDIS) show that the plume that we tracked yesterday has moved to the southeast. It is very interesting that the plume stretches over much of the REALM lidar network - from Georgia Tech and Huntsville to the south, up through UMBC and Goddard, and into NYC. Today's flightpath for the NASA DC-8, which is participating in the INTEX-NA exercise, will also traverse much of the plume. This is shaping up to be an interesting day for aerosol/smoke studies.
The Hazard Mapping System (HMS) Fire and Smoke Product clearly shows the smoke. “Analysis for day 7/19/2004 last updated at 7/20/2004 4:57:30 GMT Fires are in red. Fire size has been increased so fires are visible in this large view. Smoke, when detected by the analyst, is in gray.” (source: NOAA-SSD )
MODIS RGB images sourced from UW show smoke from the Alaska/Canada fires extending all the way into the South. Wow, this stuff got really far! It was also hazy and cloudy in Maryland today.
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IDEA AOD Images clearly point out the smoke.
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The image below on the left is the NOAA NESDIS GASP Map, which shows the AOD for the entire U.S. The large band of smoke is shown extending all the way into the South. Look at the NOAA NESDIS GASP loop to see the progression of the smoke throughout the day. The second image on the right is the UMBC developed GASP AOD animation, hazy and cloudy conditions are obvious.
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EPA AIRNow shows mostly moderate conditions around the nation. A location in California still has very unhealthy (purple dot) AQI due to fires.

A fairly uneventful day. Thick haze below the boundary layer with fairly a heavy cloud layer most of the day. The cloud layer rose from about 800m early in the day to 1.5km later. Visibility has been poor most of the day with downtown Baltimore (~12km) barely visible from the roof. If the clouds permit, we may see smoke from the Alaskan/Canadian fires tomorrow.
The following four GASP images show the progress of the AK/CA smoke for the last 72 hours. The smoke is seen to begin forming in central CA on Friday and during the next 3 days develops into an impressive band of high AOD that stretches from NE Canada down to the US Gulf Coast.
Saturday, 7/17/2004
Sunday, 7/18/2004
Today
A large fire was burning north of Los Angeles (note that the ocean is bright from sunglint in this MODIS Aqua image).
According to news reports, other fires were burning in the southwest, but they were not obvious in the satellite images, possibly due to partly cloudy skies.
Smoke from the Alaskan fires continued to cover Canada and the middle U.S., today reaching as far to the south as Louisiana. The plume was clearly visible in the MODIS Terra images.
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The smoke was also visible as very high AOD in the MODIS AOD images from the IDEA site, although the AOD algorithm eliminated the densest part of the smoke plume, possibly mistaking it as cloud.
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The smoke can be seen in the University of Wisconsin lidar image for this morning and this afternoon, passing over at about 3-4 km.
The NOAA GASP AOD also showed the smoke over the midwest, doing a little better than MODIS AOD product at sorting cloud from smoke. (Note that this image is from earlier in the day than we have been posting recently, closer to the MODIS overpass time. Later in the day the mix of the smoke with clouds reduced the AOD retrieval).
Moderate air quality at the ground level throughout the midwest and east, confirming that the smoke was high in the atmosphere.
As seen in these MODIS Terra images, Alaskan smoke was pouring into the midwest U.S. today, particularly Minnesota, Wisconsin, Iowa, the Dakotas, Nebraska, and as far south as Kansas and Oklahoma. If you look carefully, particularly at the Minnesota image, you can see that the smoke is above the clouds. The eastern U.S. is hazy-cloudy, but likely just from regional haze (not smoke)... yet. I would anticipate the smoke will come east within a few days.
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Both the smoke and the haze was clearly visible in the MODIS AOD data from the IDEA site.
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The smoke can be seen in the University of Wisconsin lidar image for today, although perhaps not as intensely as you might expect.
The NOAA GASP AOD also showed the smoke over the midwest and a haze plume off the Atlantic
Moderate air quality at the ground level through the midwest and east.
Oh my goodness! Is smoke headed our way again? It looks like a large smoke plume is moving into the U.S. I suspect that this is the same smoke from the AK/BC fires. I don't want to crowd the blog with too many images so please follow the links I provide for supplementary data. The IDEA images below show high AOD values in the Northwest, Central U.S and parts of the Northeast. The smoke plume seems to be the most intense in the North Central U.S.
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We could also see the smoke in the MODIS RGB images(sourced from UW).
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The NOAA-NESDIS GASP AOD map shows relatively the same thing as IDEA. Check out the java loop for a better look at the smoke plume moving into the U.S.

What does EPA AIRNow say? Well, it looks like the AQI is mostly moderate in the East and Central US. California has a single incidence of “very unhealthy”(purple dot) AQI, but this is not as bad as Alaska. The poor folks in Alaska have very unhealthy to hazardous AQI. Read the EPA article for more information.
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Even thought the sky was pretty clear this morning (see Dr. McCann post below) and that it is easy to see the downtown Baltimore skyline (about 12 km), this MODIS picture shows dense clouds and haze in the northeastern U.S. with Maryland being partially covered.
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On this true color picture taken by MODIS Terra, the east coast is very hazy and some clouds appear in the North. The MODIS AOD map displays no major plume over the eastern US. Another similar image can be found on the University of Wisconsin MODIS Direct Broadcast website.
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This GASP image reveals dense clouds in the northeast, the southeast and the southwest. The east coast is very hazy and the Aerosol Optical Depth is relatively low. There is an important smoke plume in Canada which is clearly visible.
The EPA declared a code purple for the Central region of California. This means that the air quality is considered “very unhealthy”. The rest of the country is relatively good with some code yellow sites in the south. See the EPA AirNow website for color bar.
Fires are still burning in the west of the U.S.. Nevada has a plume that can be visible in this MODIS Aqua picture. Next to it is the band 02,07,07 image. See MODIS AOD map.
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Ain't it great to be able to post from Matera, Italy?
Ray Rogers and I took photos of the smoke on the way out of BWI on Saturday evening and found that the layer seen in Saturday's post merged with the boundary layer just before Philadelphia. Thus they should have some increase of black carbon in NJ and NY.
Ed Eloranta's group has joined REALM and we are free to connect to UWisc images through the blog and the REALM website. Please inform those who use the UWisc data that Dr. Eloranta wishes to have a note sent to him when his data is used, what it is being used for, and what the results are.
Tom Duck told me that the Dalhousie group has received its first returns on Monday and Tuesday from Shebogue Point, Nova Scotia, and saw smoke from 3-6 km. They are extremely pleased and Dave Parrish of NOAA has seen the data.
Finally, the ash from the Fairbanks fire can definitely be seen by the UAlaska lidar of Ken Sassen....he said that he's shovelling it off the cover for his lidar.
Happy blogging.
Finally, we get a clear day. It is crystal clear (for Baltimore in July). Downtown Baltimore is clearly visible as seen in the webcam shot below. The lidars show a boundary layer at about 1km, and the aerosol return below the BL is less than half that of yesterday's brief run. A few clouds can be seen at about 4km.
Yes it was still cloudy in the Northeast! During a brief break in the clouds Dr. McCann ran the Polar Elf Lidar system (see his post below). The MODIS RGB images below sourced from UW show cloudy skies in the Northeast and a haze plume off the coast of Maryland.
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IDEA images show high AOD in the North near Canada, which might be related to the smoke from the AK/BC fires. Elevated AOD values were also located off the coast of Maryland.
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The NOAA NESDIS GASP AOD map below shows high AOD values over the Atlantic. This is possibly (I am not really too sure of the source) a mixture of haze and Sahara dust from Africa (see Jill's 07/10/04 post). The plume we saw in the IDEA images shown above (Northeast of Wisconsin) are also clearly seen in this GASP image. Fires that have been burning all week are responsible for the elevated AOD values in Washington.

Today's GASP AOD animation shows many clouds and high AOD values off the coast of Maryland.

Today's particle pollution (PM2.5) map sourced from EPA AIRNow shows mostly moderate AQI in the Southeast and West.

Canada is still bombarded with smoke from the AK/BC fires. The smoke could possibly be swinging our way again. Please follow the links bellow for images of Canada and the Northern US.
Washington continues to burn and several fires remain in California. A single fire was also found in Louisiana.
A brief respite from the heavy clouds, we have had all week. We ran for about two hours. It was still fairly cloudy with cumuls between 2 and 4 km, and heavy aerosols up to about 1 km. Visibility is still very poor with downtown Baltimore just barely visible. Then, alas, it started to rain and the hatch didn't close right away either.
We still have not had a break in the clouds this week. Between 1100Z and 1300Z this morning a solid cloud deck descended from 500m altitude to 250m. Visibility is less than 10km.
On this MODIS Terra true color image, the northern US is under a very cloudy sky.
In the Great Lakes region, the AOD is averaging 0.2.
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The eastern US is very cloudy and hazy. A plume of particles can be seen on the east coast near Maryland, over the Atlantic. The particles may be exiting or entering the continent.
Today, the AQ index is moderate in the eastern US and southern California. The rest of the country has a good AQI.
Fires are burning in the states of Washington (Terra) and California (Aqua). The smoke plumes can be seen on this RGB picture from MODIS-Aqua. The AOD in central Washington is about 0.7.
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