February 19, 2016

Air stagnation in the west continues to yield poor AQI

High pressure systems are still limiting mixing in the west and are expected to continue through the rest of the week (NWS, top left). The east remained clear while the northwest had scattered Moderate to Unhealthy for Sensitive Groups codes (AirNow, top right). Utah had an action day; it is recommended that outdoor and wood burning be limited as much as possible for this area. The National Weather Service also has air stagnation alerts in effect for the Columbia Basin. Where clouds do not impede observations, there appears to be slightly elevated AOD in Idaho, Utah, and California (VIIRS, bottom left).

February 8, 2016

Code Orange AQI in Pacific Northwest Continues

Air quality conditions were generally good today for the eastern half of the nation, with only scattered areas of Code Yellow, Moderate, air quality indices (AQIs) (top left). Code Orange, Unhealthy for Sensitive Groups, AQIs for PM2.5 were recorded again today in the Pacific Northwest/Southwest, particularly near Washington, Idaho/Montana and Utah. The highest PM2.5 levels were measured in the San Joaquin Valley area, peaking at Code Red, Unhealthy, level (top right). The elevated AQIs in California are likely related to persistent High pressure in the region (bottom left) motivating weak winds and little mixing in the atmospheric boundary layer. Today's Aqua satellite overpass also shows an artifact of high PM2.5, with elevated aerosol optical depth across the Valley (bottom right).

February 7, 2016

Code Orange PM2.5 AQI in Idaho and California

Moderate Air Quality Index (Code Yellow) was reported today through the United States. Code Orange PM2.5 AQI was reported in Idaho as a consequence of a high pressure system over this region causing poor air dispersion conditions. A different high pressure system in the southern US caused Code Yellow PM2.5 AQI, with a strong temperature inversion expected in the overnight hours to trap pollutants near the surface unitl Monday morning. Code Orange PM2.5 was also reported in the San Joaquin Valley in California. In the Great Lakes region the Code Yellow AQI was due to lighter wind speeds and the passage of a warm front that favored particle pollution formation. The Terra MODIS AOD image shows the cloudless locations impacted with this PM2.5 formation.

February 5, 2016

Fires in Southeast; High Pressure in West

The HMS fire and smoke product below left shows plumes from several fires, believed to be agricultural, in the southern Plains States, Mississippi Valley, and Southeast. Fortunately, the smoke appears to be headed out over the Gulf of Mexico and does not seem to be having a large impact on air quality in most of the area, as indicated in the EPA AQI map below right.

The AQI map also shows elevated AQIs in the Rocky Mountains States and Pacific Southwest, perhaps related to high pressure in the area. The NPS webcam image below left from Joshua Tree National Park in southern California shows some of the effects there. On the right are images taken in clear and hazy conditions for comparison.

February 4, 2016

Smoke, Dust, and Sulfate in the Gulf of Mexico

The air quality conditions today were mostly goof throughout the nation. However, few moderate levels were reached in the Great Lakes and the Pacific Northwest region (top left). Moderate levels were also experienced in California. In terms of smoke, HMS reported multiple light density smoke plumes likely associated with prescribed/agricultural burns that were seen in southeast Texas, Louisiana, western Arkansas and southeast Oklahoma. All of the smoke plumes were traveling towards the southeast with most of the smoke plumes along the Texas coastline being transported into the northwest Gulf of Mexico (top right). High aerosol optical loadings can be seen in the GASP animations most likely due to the smoke in Texas and nearby states (bottom). According to the dust reported early this week, HMS indicated that a diffuse aerosol that is likely elevated dust particles with a possible mixture of sulfates were seen in the western Gulf of Mexico. Clouds associated with a frontal boundary ahead of this aerosol limited the ability to observe the full extent of this particular matter.

February 2, 2016

Transporting Dust and smoke in the south

The Pacific Northwest, Great Lakes region, and Texas experienced Moderate AQI today (AirNow, top left). High pressure systems, reported in the NWS surface analysis, in the northwest could be the cause of the increased PM 2.5. The NAAPS aerosol model shows increased sulfates in the Great Lakes region which is likely impacting the air quality (top right). This model also indicates dust in Texas and New Mexico which has appeared to be transporting from the southwest over the past couple of days. The HMS smoke and fire products show fires and light smoke in Oklahoma and Texas (bottom left). A corresponding increased aerosol loading is present in the GASP satellite image (bottom right).

February 1, 2016

Blowing dust in California; Scattered Moderate air quality conditions elsewhere

Air quality in the United States today was generally good, with scattered Moderate conditions across the the Great Lakes, Southeast and Northeast (top left). Southern California saw the worst conditions, as strong southwesterly winds behind a departing low pressure system (top right) motivated blowing dust, thus Unhealthy/Hazardous PM10 levels across the Imperial Valley (bottom left). Today's overpass of the Aqua satellite demonstrates elevated aerosol optical depth in Pacific, juxtaposed to the California coast (bottom right). It is unclear of whether or not this is due to a dust layer aloft, albeit; NAAPS aerosol forecast is illustrating any dust in the region.