This morning, you could see hints of haze in an image from the Seattle PanoCam.
Tonight, the PurpleAir air quality network shows marginal air quality (orange and red colors) over Puget Sound.
Why the poor quality? Because of high-pressure overhead that produces a strong inversion in the lower atmosphere.
An inversion is a situation in which temperature warms with height, the opposite (inversion) of the normal cooling with elevation.
Inversions suppress mixing in the vertical, thus allowing pollutant concentrations to increase over time.
The temperature sounding this morning at Forks, on the northern WA coast, shows a profound inversion with temperature (red line) increasing by roughly 10°C (about 18F) over the lowest few thousand feet.
A similar inversion was noted at SeaTac Airport.
The inversion is the result of a strong high-pressure area (or ridge) aloft just to our northwest (see upper-level map this morning).
Such high pressure produces sinking air aloft, sinking that weakens towards the surface (see schematic below). Sinking air warms by compression (like in your bike pump) and greater sinking aloft produces strong warming aloft.
This contributes to producing an inversion.
Yes, there is a HEAT DOME overhead (but don't tell the media about it).
In addition to warming aloft, the sinking air suppresses clouds, allowing the surface to radiate heat to space, thus cooling the surface more than the air above. This also produces an inversion.
Don't worry......we have only a few more days of this situation and then the meteorological configuration will change radically.
And yes, there is a threat of lowland snow. A lot of uncertainty at this point. Will blog about it on Wednesday.
I'll be glad when the humidity goes up. My skin feels dry and I get shocked every time I take off my coat and touch a doorknob. I prefer dewpoints above about 40 F.
ReplyDeleteDewpoint alone is not a measurement of humidity.
DeleteDewpoint corresponds to absolute humidity (i.e., grams of water vapor per unit volume) at constant pressure. Relative to body temperature it is a good measure, because it corresponds to relative humidity at constant temperature.
DeleteI've noticed that despite the persistent anomalous high pressure over our region throughout the month, a temperature inversion only just set up in earnest within the past day or so. The monthly average MSLP at BLI is a very impressive ~30.40inHg/1029mb (the normal MSLP is 29.92inHg/1013mb). Why is it that an inversion only just formed despite the persistently high surface pressure? I assume some change in the mid and/or upper levels of the troposphere resulted in this occurrence but a brief explainer would be much appreciated!
ReplyDeleteSure makes beautiful chromatic sunsets
ReplyDeleteAir quality has declined recently due to several factors. Increased industrialization and urbanization have led to higher emissions of pollutants like carbon dioxide, nitrogen oxides, and particulate matter. The rise in vehicle numbers, especially in urban areas, contributes significantly to air pollution. Deforestation and agricultural practices, including the burning of crops, also release harmful gases. Additionally, the burning of fossil fuels for energy production continues to be a major source of air pollutants. Climate change exacerbates the situation, with changing weather patterns affecting air quality. Industrial waste, construction, and waste disposal practices further degrade the environment. Increased demand for transportation and energy adds to the burden on air quality. The lack of strict regulations and enforcement in some regions has worsened the situation. Finally, global and local weather patterns can trap pollutants in the air, further decreasing air quality.
ReplyDeleteIn other words, the problem, in a nutshell, is overpopulation!
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