✅3.1.1.4 - Water, Carbon and Life on Earth Flashcards
What type of feedback is sea ice melting?
Positive
How do marine phytoplankton link the water and carbon cycles?
They store carbon as living organisms, but are part of the ocean and allow formation of clouds, and therefore precipitation as part of the water cycle
What type of feedback is permafrost melt?
Positive
How does permafrost melt link to the carbon cycle?
The organic matter in permafrost can contribute CO2 to the atmosphere as it melts, impacts climate change
What is lag time in terms of climate change?
The delay between the change occurring in the climate and it having an effect
What is climate change mitigation?
Efforts made to reduce or prevent emissions of greenhouse gases
Where is the degree of ocean warming greatest?
Near the surface
How much as the ocean warmed by per decade since 1971?
0.11 degrees C
How much has global mean sea level risen by since 1901?
0.19m
Why is CO2 increase a positive feedback?
As CO2 warms the atmosphere, it results in higher evapotranspiration rates and wetter atmosphere, leading to further warming
Other than CO2, what can cause the greenhouse effect?
Water vapour, clouds, aerosols
Why is sea ice melt a positive feedback loop?
Ice reflects radiation from the sun, so less heat is absorbed
As sea ice is shrinking, less reflection and more absorption
Water warms further
Warmer waters melt ice
How do marine phytoplankton aid cloud formation?
They release a chemical substance called DMS which can lead to gormation of condensation nd clouds over oceans
Why are marine phytoplankton causing a negative feedback loop?
As temperatures warm, phytoplankton numbers increase, clouds increase, global temperatures cool
Are warmer waters more or less able to dissolve CO2?
Less
Why are water and carbon important to all living organisms?
Make up matter of people, plants, animals etc
All organisms need water to survive drinking etc
Carbon is essential for plant growth and warmth
What is one of the key links between water and carbon cycles?
Absorption of carbon in rain water, which affects the magnitude of both sources - acidic rainwater leads to weathering etc
How can changing rural land use positively affect climate change?
Planting trees can remove CO2 from the atmosphere, and fields not ploughed to retain carbon in the soils rather than being released as CO2
What are the advantages of land use changes?
Greenhouse gas emissions reduced
Reduced labour
Reforestation increases biodiversity
Floods less likely
What are the disadvantages of changing rural land use?
Reforestation needs to keep occurring to become carbon neutral
Not always more productive farming
Yield may be lowered with reduced use of fertilisers
May increase chance of wildfires
How successful is carbon capture technology?
Its complications can outweigh its benefits, as CO2 concentrations in the air are still very low and so to have a meaningful impact huge quantities of air would have to be processes.
What are the advantages of carbon capture?
Techniques well understood and easily operated, good health and safety
Fossil fuel burning plants can have carbon capture built in
Can significantly reduce emissions from plants
What are the disadvantages of carbon capture?
More energy reuqired for plants fitted with the technology, which can increase emissions indirectly
Can increase certain aspects of air pollution
Can damage environment with leakages of CO2 underground