Flashcards in Topic 9-Evolution of the atmosphere Deck (22):
What is phase 1 of the evolution of the atmosphere?
•Volcanoes released lots of gas like: Nitrogen, water vapour, methane and ammonia
•Early atmosphere mainly Co2 (like Mars and Venus)
What is phase 2 of the evolution of the atmosphere?
•water vapour condensed forming oceans
•Co2 dissolved in ocean forming carbon precipitate that formed sediments on the sea bed
•Green plants and algae evolved to carry out photosynthesis
•marine animals evolved (skeleton contained carbonates from ocean)
•carbon locked up in rocks and fossil fuel when organisms died
What forms sedimentary rocks, oil and gas?
Plants, plankton and marine animals die, get burried by layer of sediment and get compressed
What do plankton deposits form?
Crude oil and natrual gas
what do thick plant deposits form?
What do calcium carbonate deposits from shells and skelletons form?
What is phase 3 of the evolution of the atmosphere
•Green plants and Algae produced oxygen from photosynthesis
•Oxygen built up overtime to support complex life forms to evolve
What is the composite of the gases in the air today?
small amounts of other gases (Co2, noble gases and water vapour)
what type of wavelength do green house gases absorb?
What do they do with it?
They re radiate it as thermal radiation
What human activity affects amount of greenhosue gases in atmosphere?
Deforestation, Agriculture, Burning fossil fuels, creating waste
How do we know info about climate change is reliable?
Why's it hard to understand earth's climate?
•so many variables
•hard to make model thats not over simplified
What are problems with stories in the media?
Biased, only some info given
What are the 3 main consequences of Climate change?
1. Ice caps melt --> rise in sea level
2. Change in rainfall and temp --> effect crops and habitat distribution
Define carbon footprints
Measure of amount of Co2 and other green house gases released over full life cycle of something.
What are the 4 main ways of reducing carbon footprints?
1. Renewable energy sources
2. Governement tax ( could persuade people to get fuel effcient cars
3. Government cap
4. Tech that capture Co2
Why is it hard to reduce carbon footprint?
1. lots of work to develop tech
2. could effect economic growth
3.hard ot make international agreements
4. Individuals need to change lifestyle (lack of education)
What problems do particualtes in the air cause?
•Global dimming (they add to clouds which reflect sunlight back into space)
What problems does carbon monoxide cause?
•Binds to haemoglobin so less oxygen can be carried, this leads to fainting and death.
• hard to detect because its colourless and not smelly
Where does sulphur dioxide come from?
Released during combustion of fossil fuel (coal), sulfur becomes oxidised
Where does Nitrogen oxides come from?
Reaction between nitrogen and oxygen in air caused by heat (happens in internal combusion engines)