Essay On Changes In The Environment

how the environment has changed over 200 million years

The Earth’s atmosphere has changed over billions of years, but 200 million years ago, in just a brief heartbeat of geologic time, over half of all species on Earth extinct. Scientists have long tried to understand how so many species could have perished so quickly. During late century, modern researcher has tied the late-dinosaurs mass extinction that devastate changes in Earth's atmosphere that took place at about the same time. But as it is today, human have been causing the Earth’s atmosphere by burning fossil fuels and deforestation, which leads to many negative effect on the environment.

Causes

It's not entirely certain why Earth's atmosphere changed 200 million years ago. Scientists believe a series of large volcanic eruptions about 200 million years ago were the cause. These eruptions left huge lava flows along the edges of the North Atlantic and released a lot of CO2 into the atmosphere. Huge quantities of this greenhouse gas triggered global warming, which in turn melted ice that contained trapped methane and led to further warming. Increasing CO2 concentrations would also have made the oceans more acidic, another

The main gas in the Earth’s atmosphere is mainly 78% nitrogen. Oxygen- the gas that allows animals and plant to respire, and fuels to burn. Which is the most abundant gas and Oxygen only contained 21% in the Earth’s atmosphere. These two gases are both elements for about 99% of the gases in the atmosphere. The remaining gas, such as carbon dioxide, water vapour, and noble gases such as argon, are found in much smaller