EQ1 - 6.1 Flashcards
What is the carbon cycle?
A biogeochemical cycle consisting of carbon stores and fluxes between terrestrial, oceanic, and atmospheric systems.
The carbon cycle involves both long-term geological processes and shorter biological processes.
What are the two main parts of the carbon cycle?
Geological carbon cycle and biological/physical carbon cycle.
These cycles describe different processes of carbon storage and movement within the Earth system.
What is the primary store of carbon on Earth?
Most of the earth’s carbon is geological, found in sedimentary carbonate rocks and biologically derived carbon in shale and coal.
Geological carbon stores play a significant role in the long-term carbon cycle.
What is the significance of a balanced ecosystem in the carbon cycle?
A balanced ecosystem is important in sustaining Earth systems but is being upset by human activities.
Human activities can disrupt natural carbon storage and flux processes.
What is measured in petagrams (Pg) in the carbon cycle?
The amount of carbon in various stores and fluxes within the carbon cycle.
1 petagram (Pg) is equivalent to 1 billion kilograms.
What is the carbon store in the atmosphere?
589 PgC.
This represents the total carbon present in the atmosphere at a given time.
What is the rate of photosynthesis in the carbon cycle?
123 PgC/yr.
Photosynthesis is a key process that sequesters carbon from the atmosphere into biomass.
What is the rate of respiration in the carbon cycle?
118.7 PgC/yr.
Respiration releases carbon back into the atmosphere, balancing the photosynthetic uptake.
What is the rate of fossil fuel use and cement production in the carbon cycle?
7.8 PgC/yr.
This represents significant anthropogenic sources of carbon emissions.
Fill in the blank: The permafrost store contains _______ PgC.
1,700 PgC.
Permafrost is a significant carbon store that can release carbon as it thaws.
What is the estimated carbon store in sedimentary rocks?
Approximately 83,000,000 PgC.
Sedimentary rocks represent the largest carbon reservoir on Earth.
Which process contributes to carbon flux from the atmosphere to the ocean?
Atmosphere-ocean exchange.
This process involves the dissolution of carbon dioxide from the atmosphere into ocean waters.
True or False: The carbon cycle is only influenced by natural processes.
False.
Human activities significantly impact the carbon cycle, particularly through fossil fuel use and land use changes.
What is the role of rock weathering in the carbon cycle?
It contributes 0.4 PgC/yr to carbon fluxes.
Rock weathering is a natural process that helps sequester carbon over geological timescales.
What is the carbon flux from rivers to the sea?
0.9 PgC/yr.
Rivers transport dissolved organic carbon to ocean systems.
