1.A - an introduction to the water and carbon cycles Flashcards
what is life on Earth dependent on?
life on Earth is critically dependent on the abundance of water in all 3 states - liquid, vapour and ice
what is the Goldilocks zone?
- the goldilocks zone, or habitable zone, is
the range of distance with the right temperatures for water to remain liquid - all life relies on liquid water
- 3 Goldilocks conditions for life = right amount of energy, diverse chemical elements and liquids
why do PEOPLE need water?
- domestic use, showers etc
- essential resource for economic activity
- used to generate electricity, construction, irrigate crops, provide recreational facilities and satisfy public demand
- industries like food, manufacturing, brewing, paper making and steel making
- drinking water and sewage disposal
- in people (and animals) water is the medium used for all chemical reactions in the body including circulation of oxygen and nutrients
- sweating regulates temperatures by cooling people through evaporation
why do FLORA and FAUNA need water?
- transpiration of water from a leaf surface cools plants by evaporation
- photosynthesis, respiration and transpiration
- water is crucial to growth, reproduction and other metabolic functions
- also require water to maintain their rigidity (plants wilt when they run out of water)
why does the CLIMATE need water?
- water helps create benign conditions on Earth
- for example oceans, which occupy 71% of the Earth’s surface, moderate temperatures by absorbing heat, storing it and releasing it slowly
- clouds made up of tiny water droplets and ice crystals reflect around 1/5 of incoming solar radiation and lower surface temps
- at the same time water vapour, a potent GH gas, absorbs long wave radiation from the Earth, helping to maintain avg global temps almost 15C higher than they would be.
how is water important?
- makes up 65-95% of all living organisms
- allows organic molecules to mix and form complex structures
why is carbon so important?
- it is the chemical backbone to life on Earth (in part due to carbon’s ability to readily form bonds w/ other atoms)
- life as we know it is carbon based and built on large molecules of carbon atoms such as proteins, carbohydrates and nucleic acid.
- used as an economic resource (fossil fuels such as coal, oil and natural gas power the global economy)
- oil is used as a raw material in the manufacture of products ranging from plastic to paint.
- agricultural crops and forest trees also store large amounts of carbon available for human use as food, timber, paper, textiles and many other products
- essentially, carbon compounds regulate the Earth’s temperature, make up food and provide energy to fuel the global economy
what are the forms and uses of carbon on Earth?
- carbon is stored in carbonate rocks such as limestone, sea floor sediments, ocean water (as dissolved CO2), the atmosphere (as CO2 gas) and in the biosphere.
- life as we know it is carbon based and built on large molecules of carbon atoms such as proteins, carbohydrates and nucleic acid.
- used as an economic resource (fossil fuels such as coal, oil and natural gas power the global economy)
- oil is used as a raw material in the manufacture of products ranging from plastic to paint.
- agricultural crops and forest trees also store large amounts of carbon available from human use as food, timber, paper, textiles and many other products
whats the difference between an open and closed system?
- OPEN = energy and matter can be transferred to neighbouring systems as an input/output
- CLOSED = a system w/inputs and outputs of energy, but w/o any movement of materials across boundaries
what are the global water and carbon cycles?
CLOSED SYSTEMS
- the amount of water and carbon within our planet stays the same
- the amount in one particular store (such as carbon in our atmosphere) may change but globally the figures are constant i.e. there is no matter being added or lost
- at smaller scales such as mountain stream (water) or a compost heap (carbon), the systems may be thought of as open, because the amount of water or carbon will vary over time
what is equilibrium?
a long term balance between inputs and outputs in a system
what is dynamic equilibrium?
a lack of change in a system as inputs and outputs remain in balance
what is NEGATIVE FEEDBACK?
an automatic response to a change in a system that RESTORES EQUILIBRIUM
what is POSITIVE FEEDBACK?
an automatic response to a change in a system that GENERATES FURTHER CHANGE
