Post by Derek Mallia on Aug 17, 2013 19:22:40 GMT
While this may not be as exciting as a landfalling TC or a tornado, distant wild fires can have major impacts on downstream urban areas areas (recall the Quebec fires on 2002). Currently there is a fairly large wild fire located 50 miles west of Salt Lake City (see here). While the area that is being impacted by burning is very rural this fire has still made the news for the effects it is having on downstream urban sites which in this case is Salt Lake City. These impacts mainly come in the form of increased concentrations of green house gases (CH4 and CO2), CO, and aerosols such as PM 2.5. The increase in CO2 concentration is especially evident in local observation sites that are maintained by the University of Utah. Over the course of the past few days we've had weak flow out of the west along with relatively stable conditions. This has kept the concentration of pollutants high near the surface along with pushing it towards Salt Lake City as seen in the attached photo:
Sites on the eastern edge of the valley have seen a modest increase of CO2 as seen here. Generally you have a peak of CO2 during the morning when traffic emissions are high coupled with a lower PBL and a minimum later in the day when you PBL is much higher (hence more mixing into the free troposphere which dilutes the concentration of CO2 near the surface. CO2 measurement sites across the western side of the Salt Lake Vally experience a more sudden increase of CO2 as they are located closer to Patch Springs. CO2 from fires can also be used as a tracer for other species such as PM 2.5 which can have negative health impacts on the general population.
Sites on the eastern edge of the valley have seen a modest increase of CO2 as seen here. Generally you have a peak of CO2 during the morning when traffic emissions are high coupled with a lower PBL and a minimum later in the day when you PBL is much higher (hence more mixing into the free troposphere which dilutes the concentration of CO2 near the surface. CO2 measurement sites across the western side of the Salt Lake Vally experience a more sudden increase of CO2 as they are located closer to Patch Springs. CO2 from fires can also be used as a tracer for other species such as PM 2.5 which can have negative health impacts on the general population.
