Exporting Pollution to Utah County

 With the passage of a weak weather system and deepening (but not removal) of the cold pool in Salt Lake Valley, the northerly winds on New Year's Eve led to considerable transport of pollution into Utah County  where the cold pool had mixed out. The winds at Flight Park South illustrate the strong northerly winds during the afternoon.

End-of-Year Poor Air Quality Event

The steam plume on December 28 from the Lake Side power plant in Utah County highlights the lack of  wind within the shallow cold pool and the strong stability limiting the plume's height.

Moderate air quality throughout the period with good coverage from sensors onboard TRAX and Ebuses. 

Unsaturated conditions help keep PM2.5 readings from DAQ and research sites similar.

 

December 19 Timelapse: Fog within Shallow Cold Air Pool

Impact of downslope easterly wind event on air quality: 13 December

 Strong downslope winds developed overnight on 13 December 2023. Hig winds extended westerward across the Valley. Note the turning of the wind to the north and south in the western portions of the Valley.

Mobile PM2.5 observations help to illustrate the clean air resulting from the easterly winds relative to higher PM2.5 concentrations in other areas to the north and south.

November 27-December 2 AQ Event

  The second  AQ event of the winter 2023-2024 season developed during the last week of November.

Time series at Hawthorne showing the increase in PM 2.5 on 29 November that resulted from an increasingly shallow boundary layer over the several day period.

The ceilometer on the valley floor highlight the boundary layer depth on the 29th.

Thanksgiving Inversion

Interesting air quality event around the Salt Lake Valley over Thanksgiving. I had the chance to get a window seat and flight path out of KSLC that wrapped around the Oquirrh mountains:

Background air quality / particulate matter (PM) map via https://utahaq.chpc.utah.edu/, annotated flight path marked with red arrow 

Webcams installed at the University of Utah campus on top of the William Browning Building showed less than ideal air quality that morning: 

UofU / William Browning Building (WBB) / current home of the Atmospheric Sciences Dept.      Rooftop webcam, looking WEST, 10am local. 

Ground monitoring stations throughout the Salt Lake Valley measured PM2.5 values between 10-20 µg/m3 on the second day of this inversion period:

 

 From the sky, this event was widespread through the Salt Lake Valley:

 The cold air pool wrapped around the Oquirrhs into the Tooele valley:

 

 Conditions improved the next day as a low pressure system blew into the valley and cleared out the stagnant air: 

Real-time provisional data measured at the UofU / Mountain Meteorology weather station:        MesoWest - MTMET

 Unfortunately, not the only inversion we've had this Winter. Not the worst for maximum PM either:

 

 Our group has a variety of real-time research tools to study, understand, and analyze these events. Click around any of the links above and/or check out https://horel.chpc.utah.edu/ for more information.