About: http://webisa.webdatacommons.org/272674625

Property	Value
http://www.w3.org/1999/02/22-rdf-syntax-ns#type	http://www.w3.org/ns/prov#Entity
http://www.w3.org/ns/prov#value	These are very challenging to estimate as they depend on various factors such as traffic volumes, emission inventory, predominant winds, geography, etc.
http://www.w3.org/ns/prov#wasQuotedFrom	gazette.gc.ca