Wildfire Smoke Brought Enhanced Radioactivity and Ozone

Now many folks were unhappy with the low visibility and dismal skies during our wildfire smoke period.  And I know a number of you were discomforted by the particles in the air.

But there is more.   According to U.S. government measurements, radioactivity and ozone were higher as well.

I wasn't aware of the radioactivity issue until I received an email from Tim Celeski of WeatherOLA.com who provided a link to the Environmental Protection Agency's RadNet website (another good reason why we need EPA, by the way).

Here is the gamma radiation count from Seattle. Gamma radiation is very high energy electromagnetic radiation and are capable of ionizing (stripping electrons) from atoms.  Values jumped up on August 3, when the smoke reached Seattle and started to decline yesterday.  Note that is a logarithmic scale so the jump is significant.

 They also break the radiation down by energy range.  Similar story.

Wildfires inject burned and other materials into the air, and if any long-lived radioactive materials (like Cesium-137) attach to the smoke particles, they can travel substantial distances.  As noted by two colleagues of mine at WSU (Brian Lamb and Yunha Lee), such suspension of radioactive material by wildfires has been observed and studied before.

So where did the radioactivity come from in the soils and plant materials in the area of the BC fires?  I am no expert in this, but one could speculate there could be deposition from the Fukushima event, the remnants of previous above ground atomic testing, or perhaps natural radioactivity in the soils.   Perhaps one of you knows more about this.

And then there was ozone...VERY high levels of ozone that were produced by the numerous BC fires.  

Fires produce nitrogen oxides and hydrocarbons that can combine to produce ozone. . According to my UW Bothell colleague (and a specialist in NW atmospheric chemistry)  Dan Jaffe, the ozone levels were stunning.

8hr average values at Enumclaw hit 103 and sites near PDX reached 116.   And many sites that don't usually exceed the standard, like Eugene, were way over.

This chart shows maximum 8-hr ozone averages on August 3.  Reds are very high.

The U.S. ozone standard is based on a maximum amount of 70 parts per billion (ppb).  Specifically, an area will meet the standards if the 4th highest maximum daily 8-hour ozone concentration each year, averaged over three years, is 70 ppb or below. Ozone can irritate the lungs and sensitive nasal passages.

In total, Enumclaw has been over the 70 ppb standard  for 8hr on 8 days since 7/31. Wow.

How about Mud Mountain Dam (near Mt. Rainier) and Issaquah (see below)?  Lots of times above 70 ppb!

According to Dr. Jaffe, we have not seen O3 like this in decades.

So with smoke adding lots of particles into the atmosphere (documented in previous blogs), high ozone levels, a depressing sky with little visibility, and some radioactivity thrown in for good measure, it is no wonder some folks were not feeling so good during the last week.



from Cliff Mass Weather and Climate Blog http://ift.tt/2w2ksso