Flashcards in Chapter 4- Climate Change Deck (22):
How is carbon dioxide formed and removed ?
Released into atmosphere by cell respiration, combustion of biomass and fuels- removed by photosynthesis and dissolving in the oceans
How is water vapour formed and removed?
Formed by evaporation from the oceans and also transpiration in plants - removed by rainfall and snow
What are other green house gases
Methane and nitrogen oxides
How is methane produced?
3rd most significant greenhouse gas- it is emitted from marshes and other waterlogged habitats and from landfill sites- released during extraction of fossil fuels
How is nitrous oxide released?
Released matti ally by bacteria in some habitats and also bt agriculture and vehicle exhausts
How much % does green house gases make up
1% of the atmosphere
What are the 2 factors that determine the warming impact of a green house gas?
1) how readily the gas absorbs long wave radiation
2) the country concentration of the gas in the atmosphere
What does the concentration of the gas depend on?
On the rate at which it is released into the atmosphere
What does the warmed earth emit?
The warmed surface of the earth absorbs short-wave energy from the sun and then re-emits it but at much longer wave lengths
What are most the of re-emitted waves
Radiation is infrared
How much radiation from the sun of short wave lengths is absorbed before it reaches it reaches the earths atmosphere?
However a far higher percentage of the longer wavelength radiation re emitted by the surface of the earth is absorbed before it has passed out so space which means how % is absorbed by green house gases
70% to 85%- which causes global warming
If the concentration of any greenhouse gases in the atmosphere changes what can we expect to happen?
The size of its contribution to the greenhouse effect to change and global temperatures to rise or fall
How can we test the carbon dioxide concentration of the atmosphere in the past?
Columns of ice have been drilled in the Antarctic, the ice has built up over thousands of years, so Ice from deeper down is older than ice near the surface - bubbles of air trapped in ice can be extracted and analysed to find co2 conc
There is a correlation between co2 concentration and global temps what is it
The periods of higher co2 concentration repeatedly coincide with period when the earth was warmer
What is the hypthosjs from global temps and co2 conc correlation ?
That rises in co2 conc increase the greenhouse effect
If concentration of greenhouse gases increased what would be expect to happen
Increase in global average temps
What other global temps influence other aspects of climate?
1) higher temperatures increase the evaporation of water from the oceans and therefore periods of rain are likely to be more freqjent
2) higher temps cause tropical storms and hurricanes to be more frequent and harmful
What would the consequences of any rise in the global average tenp be
Unlikely to be evenly spread out - not all areas would become warmer- distribution of rain fall would change etc
What is the correlation between industrilziafikn and climate change?
The atmospheric concentration of carbon dioxide has been rising since the start of the industrial revolution 200 years ago and average global temps
What are recent increases in atmospheric carbon dioxide largely due too
Combustion of fossilised organic matter