this web poll is powered by micropoll.com. try it yourself. 
MicroPoll  »  Polls By Lloyd Alter  » 
What was the concentration of atmospheric carbon dioxide before the Industrial Revolution?
a) 120 parts per million
b) 200 parts per million
c) 280 parts per million
d) 439 parts per million
Submit Answer
Total Votes : 492
Powered By MicroPoll
Author
Lloyd Alter
Web Poll Powered By MicroPoll
Poll Link : http://www.micropoll.com/akira/mpview/254176-82037
© Survey Analytics 2009