Summary Edexcel iGCSE Biology Revision notes on the greenhouse effect

What is the greenhouse effect?
The greenhouse effect is a natura
process that occurs when greenhous
gases (like CO2 methane , nitrous
,

dioxide and CFCs (Chloroforo-
carbons)) in the atmosphere trap hea
from the Sun Warming
,
the Earth's
surface. Although this process is

necessary for life on Earth
, an
increase in greenhouse gas
concentrations leads to global
warming and climate change
What causes it?
There are many contributing factors to
the increase of greenhouse gases in the

atmosphere but humans are responsible for
almost all of the increase in the last 150

years by doing things like :
burning fossil fuels like coal and oil

(for electricity ,
heat and transportation)
cutting downforests
farming livestock
·
using transportation (like cars rather
than trains
consuming too much meat (and

generally other foods)
agriculture

What are the consequences?
Greenhouse gases have far-ranging
environmental and health effects like :



climate change
- caused by the greenhouse gases trapping th

heat absorbed by the Sun thus warming
the Earth
(contributes to respiratory disease
↳ from
smog and air polution
·
extreme weather
food supply disruptions
increased wildfires