B7 Global Warming (page 92) Flashcards
What do Carbon Dioxide and Methane do to the earth?
It traps energy from the sun.
The temperature of the Earth is a balance between what?
a balance between the energy it gets from the Sun and the energy it radiates back out into space.
Gases in the atmosphere naturally act like an insulating layer, how?
They absorb most of the energy that would normally be radiated out into space, and re-radiate it in all directions (including back towards the earth.
(This increases the temperature of the planet)
This is what happens in a greenhouse. The sun shines in, and the glass helps keep some of the energy in.
If the atmosphere didn’t act like an insulating layer, what would happen?
If this didn’t happen, then at night there’d be nothing to keep any energy in, and we’d quickly get very cold indeed.
There are several different gases in the atmosphere which help keep the energy in, what are they called?
“greenhouse gases”
What are the main greenhouse gases we worry about and why?
the main ones we worry about are Carbon Dioxide (CO2) and Methane - because the levels of these two gases are rising quite sharply.
We worry that this is getting a bit out of hand.
look at picture on page 92.
What do Global Warming mean?
Global warming is a type of climate change and causes other types of climate change, e.g. changing rainfall patterns.
The Earth is gradually heating up because of the increasing levels of greenhouse gases - global warming.
There are several reasons to be worried about global warming, name some?
Higher temperatures
distribution of many wild animal and plant species
changes in migration patterns
Biodiversity (see page 91)
Why is Higher temperatures a concern for global warming?
Higher temperatures cause seawater to expand and ice to melt, causing the sea level to rise. It has risen a little bit over the last 100 years. If it keeps rising it’ll be bad news for people and animals living in low-lying places. It will lead to flooding, resulting in the loss of habitats (where organisms live).
Why would Global Warming affect the distribution of many wild animal and plant species?
this may change as temperatures increase and the amount of rainfall changes in different areas.
Some species may become more widely distributed. e.g. species that need warmer temperatures may spread further as the conditions they thrive in exist over a wider area.
Other species may become less widely distributed, e.g. species that need cooler temperatures may have smaller ranges as the conditions they thrive in exist over a smaller area.
Why would Global Warming affect changes in migration patterns?
e.g. some birds may migrate further north, as more northern areas are getting warmer.
Why would global warming affect Biodiversity?
Biodiversity could be reduced if some species are unable to survive a change in the climate, so become extinct.
Global warming is rarely out of the news. Most scientists accept that it’s happening, but who is to blame?
human activity is the cause of most of the recent warming. However, scientists don’t know exactly what the effects will be.
Explain how global warming could lead to the loss of low-lying habitats (3 marks)
Global warming causes higher temperatures which cause ice to melt and seawater to expand (1 mark).
This causes the sea level to rise (1 mark)
which could lead to flooding of low-lying land and therefore the loss of habitat (1 mark).
