title: Earth day plus 40.
authors.affiliation: est@uiowa.edu
authors.forename: Jerald L
authors.initials: JL
authors.lastname: Schnoor
mesh_terms: D000846:Anniversaries and Special Events; D018534:Earth, Planet; D004463:Ecology / Q000266:history / Q000639:trends; D004777:Environment; D005398:Fisheries; D017752:Greenhouse Effect; D049673:History, 20th Century; D049674:History, 21st Century; D014481:United States; D014484:United States Environmental Protection Agency