Climate Change June 6, 2022 The last Time our Atmosphere had 421 ppm of Carbon Dioxide, Florida was under Water and Giant Camels and Rhinoceri roamed Indiana Source: The last Time our Atmosphere had 421 ppm of Carbon Dioxide, Florida was under Water and Giant Camels and Rhinoceri roamed Indiana Rate this:Share this:RedditPinterestPocketEmailLinkedInTumblrTelegramWhatsAppSkypeLike this:Like Loading... Related