https://padlet.com/brittomi24/eaa6i5hd4c9owoyx en-us 2023-07-16 19:30:40 UTC 2023-07-16 21:01:50 UTC hello@padlet.com brittomi24 https://padlet.com/brittomi24/eaa6i5hd4c9owoyx/wish/2645844958 4.6 billion years ago when the Earth first formed, there was little to no atmosphere to keep gasses trapped by the surface like there is today. Instead, the molten surface of the Earth allowed volcanoes to erupt and release gasses like ammonium and methane. Earth was completely uninhabitable. 
The Earth began to cool after around 500 million years and water began to form and fill trenches. ]]> 2023-07-16 20:20:23 UTC https://padlet.com/brittomi24/eaa6i5hd4c9owoyx/wish/2645844958 brittomi24 https://padlet.com/brittomi24/eaa6i5hd4c9owoyx/wish/2645846507 With a methane haze covering most of the Earth and no oxygen gas in the atmosphere, there was no life on the surface. Within the water however, chemical reactions created simple cell organisms that could survive on other elements like sulfur. As time went on, cyanobacteria started to form 2.7 billion years ago. The formation of this bacteria was fundamental to the creation of the atmosphere as we know it today. They began to partake in the process of photosynthesis, releasing oxygen gas into the atmosphere. Because of the cyanobacteria 21% of the atmosphere filled with oxygen gas, the same amount we have today. ]]> 2023-07-16 20:31:31 UTC https://padlet.com/brittomi24/eaa6i5hd4c9owoyx/wish/2645846507 brittomi24 https://padlet.com/brittomi24/eaa6i5hd4c9owoyx/wish/2645847399 As oxygen continued to accumulate from photosynthesis, plant life grew. As time went on, life began to grow more complex. Chemical reactions continued and the methane gas began to disappear and the sky turned blue as we know it today. Evidence of oxygen in the atmosphere can be seen through oxidized iron in rocks that create a red color known as red beds. ]]> 2023-07-16 20:38:20 UTC https://padlet.com/brittomi24/eaa6i5hd4c9owoyx/wish/2645847399 brittomi24 https://padlet.com/brittomi24/eaa6i5hd4c9owoyx/wish/2645849319 As plants and animals thrived during this time period, the oxygen levels fluctuated between 20%-35%. And although when animals die carbon dioxide is released, because many animals died in swamps and had little time to decay, the lowered carbon dioxide in the atmosphere caused the Earth to cool. The remains of these dead animals will settle and become buried to form fossil fuels. The carbon dioxide that was not emitted then is now being emitted now through the burning of fossil fuels, raising atmospheric temperatures. ]]> 2023-07-16 20:52:45 UTC https://padlet.com/brittomi24/eaa6i5hd4c9owoyx/wish/2645849319 brittomi24 https://padlet.com/brittomi24/eaa6i5hd4c9owoyx/wish/2645850934 Compared to now, the Earth was much warmer, harboring life around the poles as the equator was too hot for most organisms. It is most likely that the Earth was hotter due to high carbon dioxide levels. 
Now, the Earth is cooler compared to 290 million years ago but temperatures are slowly rising due to heightened carbon dioxide emissions. The total effects of mass carbon dioxide emissions are unclear but effects can already be seen through a thinning ozone layer and unpredictable weather patterns that harm all life. ]]> 2023-07-16 21:01:50 UTC https://padlet.com/brittomi24/eaa6i5hd4c9owoyx/wish/2645850934