Why Does Climate Change Flashcards
What is greenhouse effect
Greenhouse effect is when solar radiation from sun contains infrared radiation (heat). Some of the solar radiation is reflected back into space by the Earth’s atmosphere, some penetrates the atmosphere. Infrared radiation reaches Earth’s surface at short wavelengths and absorbed by earths surface. Infrared absorbed by Earth’s surface is radiated back at longer wavelengths. Some of this radiation is absorbed by greenhouse gases (C02, methane) and radiated back to earths surface, warming it.
Why has number of greenhouse gases increased
Number of greenhouse gases has increased because of more fossil fuels being burnt. E.g oil, coal, gas.
Also, increased deforestation (increases CO2) and digging up peat bogs
When is methane produced
Methane is produced by livestock, wetlands (e.g rice paddy fields) and landfills. Large bubbles of methane are frozen within arctic permafrost.
Has increased because more decaying waste and more heat means frozen bubbles release methane
Incomplete combustion
Can be reduced through improved recycling and using it as a biofuel. Stays for 12 years
Why is nitrous oxide produced
Nitrous oxide is produced from combustion of fossil fuels, industrial processes and fertilisers. More potent than methane and c02 but less common
Why does carbon dioxide have the largest greenhouse effect
Carbon dioxide has the largest greenhouse effect because it is far more abundant than other greenhouse gases that have a greater effect and C02 stays in the atmosphere for about 150 years, more than any other gas.
What is a controversial issue
A controversial issue is when alternate points of view about it can reasonably be held
Why is climate change a controversial issue
Climate change is a controversial issue because scientists cannot prove theories, scientific methods can only disprove them. Because if results support a hypothesis , there could be alternate situation.
There is incomplete knowledge of how the climate systems of our planet work and the day set used in predictions about climate change have limitations. E.g there is no way to measure exactly how much C02 is added by fossil fuel combustion and some people use uncertainty to dismiss link between rising C02 levels and global warming.
No direct evidence that increased C02 leads to global warming
What are ethical arguments when considering global warming
Ethical arguments are
We all have right to choose for ourselves whether or not we use fossil fuels to achieve a good standard of living.
We have a duty to allow others to improve their standard of living
We have duty to preserve environment for next generation.
What is global warming
Global warming is general increase of global mean surface temperature (an average of measurements made in many places in the world) due to enhanced greenhouse effect due to raised concentration of C02 and methane in atmosphere. This traps more infrared radiation increasing global mean surface temperature (GMST) due to an accelerate greenhouse effect.
How to work out relative contribution of a gas to greenhouse effect
Relative contribution of a gas to greenhouse effect = %abundance x global warming potential
What is a theory
Theory is a well tested and widely accepted idea/principle
Compare global warming and greenhouse effect
Global warming is general increase of global mean surface temperature (an average of measurements made in many places in the world) due to enhanced greenhouse effect due to raised concentration of C02 and methane in atmosphere whereas greenhouse effect is a way of why this is happening (trapping heat) but greenhouse effect is theory, it is widely believed but it may be caused by other things e.g changes in solar radiation.
Why is C02 produced
C02 is produced in burning of fossil fuels, deforestation and evaporation of ocean (it has locked up carbon)
