Costanza: re-reading your message, I realized that I didn't fully answer
your question. My data does show likely leveling off of the accumulation
build-ups of dirt on streets, after long periods of time of little rain. It
is not a straight line, precisely due to the reasons you mentioned:
turbulence removal of very high loads due to natural winds and from traffic.
In my 1979 San Jose report, I reported fugitive dust loss measurements of
these losses. In may parts of the US, with relatively short inter-event
periods, the rate looks like a straight line, as it generally may take about
a month for the loadings to level off. This was reflected in my earlier
email attachment table. I am attaching a figure (based on my 1979 EPA
report) here, showing this leveling-off effect.
Bob
Robert Pitt, P.E., Ph.D., DEE
Professor
Department of Civil and Environmental Engineering
University of Alabama at Birmingham
1075 So. 13th St.
Birmingham, AL 35294-4440
voice: (205) 934-8434
fax: (205) 975-9042
email: [log in to unmask]
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