C18 Earth's atmosphere Flashcards
Name 3 greenhouse gases
Carbon dioxide
Water vapour
Methane
What is the atmosphere?
A layer of gas surrounding the Earth
What was the Earth’s atmosphere mostly composed of?
CO2
How did the oceans form?
Water vapour condensing as the Earth cooled
How did the amount of CO2 in the atmosphere decrease to todays levels?
-Dissolved in oceans
-Photosynthesis
-Fossil fuels
-Precipitated as insoluble
metal carbonates
When did life start to appear?
2.7 billion years ago
How did the beginning of life impact oxygen in the atmosphere?
Oxygen was more present due to photosynthesis
How has nitrogen in the atmosphere changed over time?
Increased slowly because it is a very stable molecule
Why can scientists not entirely be sure about early Earth’s atmosphere composition?
As evidence is limited and as it was very long ago
What is the current composition of Earth’s atmosphere?
80% nitrogen
20% oxygen
Trace amounts of CO2, water vapour and noble gases
What is a greenhouse gas?
A gas that traps radiation from the sun
What type of radiation do greenhouse gases absorb?
Infrared radiation
2 ways methane levels have increased due to human activity
Rice farming
Cattle farming
2 ways CO2levels have increased due to human activity
Fossil fuels
Deforestation
What is global warming?
Increase in the overall global average temperature
What is global climate change?
The change in long-term weather patterns across the planet
Effects of climate change
Sea levels rising
Extreme weather events
Changes in ecosystems
Polar ice caps melting
What is a carbon footprint?
Amount of carbon a product or person has released in to the atmosphere over its lifetime
How is carbon monoxide formed?
Incomplete combustion
Why is carbon monoxide dangerous?
Colourless and odourless toxic gas
What are particulates?
Soot and unburnt hydrocarbons
Where do particulates originate from?
Diesel engines
Incomplete combustion
What effect do particulates have on the environment?
Global dimming
Respiratory issues
How is sulfur dioxide formed?
From sulfur impurities in fossil fuels
What dangers are associated with sulfur dioxide?
Acid rain
Respiratory issues
How are oxides of nitrogen formed?
Atmospheric oxygen and nitrogen react in the heat of a combustion engine
What problems are associated with oxides of nitrogen?
Acid rain
Respiratory issues
