🚀 go-pugleaf

In article <JMC.96Jan4203515@Steam.stanford.edu>,
John McCarthy <jmc@cs.Stanford.EDU> wrote:
>The top of Mount Wilson 5740 feet is above the smog and the inversion
>layer.  For this reason it has some of the best seeing in the U.S.
>Sallie Baliunas told me this.
>-- 

Don't count on it.

I have done quite a bit of of hiking in the Angeles and 
San Bernardino National Forests, and I have seen 
(and been in) pretty bad smog at elevations much higher 
than 5800 feet.

I remember going to the top of Mount Wilson on a 
smoggy summer afternoon a number of years ago.  I was in 
the smog, not above it.

A few summers ago, I day-hiked San Gorgonio with a few friends.
It was crystal-clear in the early morning, but by about 4 in the
afternoon, the smog had ascended to nearly 9000 feet. By the
time that we got back to the trailhead in Mill Creek Canyon,
we all had the classic ozone-induced chest-tighness sensations.
It was somewhat uncomfortable to inhale or exhale very deeply.

I have found it advisable to get an early start on summertime
hiking trips in the San Gabriel or San Bernardino Mountains.
It's no fun chugging uphill (especially with a pack) when
the afternoon smog rolls in... 

I have noticed that the air quality is not as bad as it
used to be, but it still has a way to go before it is
truly fit for hiking in.