• Question: How has the atmosphere changed overtime, since maybe the Big Bang?

    Asked by vjstar98 to Davie, Gemma, James P, James V, Nuala on 29 Jun 2012.
    • Photo: James Pope

      James Pope answered on 29 Jun 2012:

      Hi vjstar98,

      Our Earth is 4.5 billion years old, which is actually much younger than the universe and the big bang. The early atmosphere was very different to todays atmosphere with the main gases being Water Vapour, Carbon Dioxide, Sulphur Dioxide, Nitrogen, Hydrogen, Ammonia and Methane. About 3.5 billion years ago, photosynthesising single celled organisms came into existence and this allowed oxygen to be formed in the atmosphere, and eventually we reached a level of oxygen about what we have today. If this hadn’t happened we wouldn’t be able to exist as to develop large complex life with bones and shells you need a good amount of oxygen in the atmosphere. This happened over 2 billion years, during which time the atmosphere evolved to become similar to how it is today.

      The addition of oxygen is probably the biggest change to our atmosphere that has happened since the Earth was formed.

    • Photo: Nuala Carson

      Nuala Carson answered on 2 Jul 2012:

      Hey vjstar98,

      The earths atmosphere has changed immensely since the earth was created. James has given you a good answer here. I would add that carbon dioxide was much more abundant in the early earths atmosphere, but humans couldn’t survive because of the very high temperatures!

Comments