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I recently heard (it may have been here) of a new sign counting up 
carbon emissions for the year. I'd like to do something similar here, 
but in checking the math, I can't get the original sign's numbers to 
work right. Any help appreciated. Here is the text I used (from Pac Sci 
Ctr site):

"The sign began at zero on January 1 of this year, and increases by one 
metric ton every 45 seconds. Our emission rate is based on a 2003 King 
County study which found the county emits nearly 23 million metric tons 
of carbon dioxide each year."

I found Maryland (the entire state) to emit about 80 million metric tons 
per year. So, from high school conversions, I tried to find mmt/sec as 
PSC did: 80 mmt/yr x 1yr/365dy x 1dy/24hr x 1hr/60min x 1min/60 sec = 
2.54 mt/sec

Taking the reciprocal, I get 1 metric ton every 0.39 seconds, which is 
off what I estimate it should be, according to PSC's calculations (80 
mmt is about 4 times 23mmt, so we should produce emissions about 4 times 
as fast, or about 1 mt every 10 seconds, not 1mt every 0.4 seconds). So 
far, I haven't received any answer from PSC. Thoughts?

-- 
--
Kathryn Stofer
TerraLink Exhibit Manager
Maryland Science Center
601 Light Street
Baltimore, Maryland 21230
410/545-5976
410/545-5974 fax
BODYWORLDS - Coming to MSC Feb. 2 - Sept. 1, 2008!


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