global carbon cycle

hydrolysis of calcium silicate

CO2 reacts wil water to form a weak carbonic acid which weathers calcium silicate rocks, takes CO2 from the atmosphere

Chemical weathering as a mechanism for the exchange of carbon between the atmosphere and geosphere. role of H2CO3 (carbonic acid)

Carbonic acid, formed when carbon dioxide dissolves in water, is the acid used to weather rocks This weathering creates bicarbonate ions which then enter the ocean and result in use by marine animals for making shells

Diurnal and seasonal cycles of atmospheric CO2

Diurnal and seasonal cycles of atmospheric CO2 daily changes in CO2 and sunlight measured over the forest floor diurnal: CO2 concentrations highest at night and early morning when plant respiration dominates; values decline during day as CO2 is used by photosynthesis seasonal: CO2 concentrations highest during winter/spring when respiration dominantes; values decline during summer/fall when photosynthesis is using up CO2 higher sunlight = lower CO2 highest CO2 at night and lowest during the day due to photosynthesis and respiration (happen during the day, during the night only respiration so more CO2 in the atmosphere) more photosynthesis in the spring and summer so lower CO2 larger variation in the northern hemisphere because more land

carbonate-silicate cycle serves as a negative feedback on the temperature of the earth system

Initial change--warmer climate--increased temperature, precipitation, vegetation--increased chemical weathering--increased CO2 removal by weathering--reduction of initial warming

Volcanoes and subduction as mechanisms for the exchange of carbon between the geosphere and atmosphere

Limestone deposits get subducted into earth's crust where high temp cause calcium carbonate to undergo metamorphosis into calcium-silicate rock; Calcium carbonate releases carbon dioxide during transformation. These carbon dioxide molecules find way back to surface through volcanic eruptions and hydrothermal vents. Calcium-silicate rocks will then be lifted in emerging crust where it will be weathered thus completing the cycle limestone not permanent, ocean crust moves down in the subduction zone and is melted back to calcium silicate rock while CO2 is released back into the atmosphere through volcanoes and hot springs

How does chemical weathering act as a mechanism for the exchange of carbon between the atmosphere and geosphere?

Weathering is a mechanism that removes carbon from the atmosphere When carbon dioxide dissolves in water (rain droplets), it forms carbonic acid, which is used to weather rocks, yielding bicarbonate ions dissolving by water, reaction w/ acids, or reaction with oxygen, that change the composition of rocks The bicarbonate ion enters oceans through fresh water systems, and in the ocean, the bicarbonate ion combines with a calcium ion to form calcium carbonate, used by marine organisms to form shells

Chemical weathering as a mechanism for the exchange of carbon between the atmosphere and geosphere. role of CaSiO3 (calcium silicate)

Weathering of silicates in minerals releasing calcium silicate, which is combined w/ carbon dioxide to form limestone The limestone locks away carbon from the atmosphere for a long time

role of chemical weathering in the oxygen cycle

When an oxygen bearing mineral is exposed to the elements a chemical reaction occurs that wears it down and in the process produces free oxygen

role of photolysis in the oxygen cycle

a source of atmospheric oxygen comes from photolysis, whereby high energy ultraviolet radiation breaks down atmospheric water into component atoms Process that involves high energy sunlight breaking apart oxygen bearing molecules to produce free oxygen water vapor bombarded with high energy, splits atoms into hydrogen and oxygen, oxygen is used in the oxidation of rocks

highest

carbon dioxide concentrations are ___________ at night and early morning when plant respiration dominates, however it declines over the days as carbon dioxide is taken up in photosynthesis

what has been the general trend in atmospheric concentrations of CO2 over Earth's history (past 4 billion years)?

concentration of atmospheric CO2 rising due to burning of fossil fuels, especially coal and petroleum From analysis of trapped air in Antarctic ice sheets, CO2 has spiked immensely from 1800 to 1900 to a huge increase to 2000

organic sedimentary rocks

consist of lithified remains of plants or animals coal is an organic sedimentary rock made up of decomposed and compacted plant remains

source of fossil fuels

dead organic matter/soil

long term inorganic carbon cycle

emphasis on calcium carbonate (CaCO3, limestone), by far the largest of the carbon reservoirs the cycle is linked to the carbonate-silicate, supplying the calcium ions necessary for the formation of limestone occurs on a much slower time scale carbon from the atmosphere to the geosphere

Long-term organic carbon cycle

emphasis on the formation and destruction of fossil fuels and other sediments containing organic carbon carbon not fully decomposed occurs on a much slower time scale

What processes led to the period of elevated atmospheric O2 during the Carboniferous period (250-450 million years ago)?

high amounts of organic material being decomposed, need to do something else w/ carbon besides decompose it because uses oxygen to decompose, end up burying carbon appearance of terrestrial ecosystems and no substance to decompose them increased burial of organic carbon

General patterns of carbon storage in living vegetation and soils (as they relate to our discussion of global patterns of net primary and ecosystem productivity),

highest in living plants in the wet tropics and equatorial zone due to high decomposition living vegetation: highest amount of carbon stored along tropical (equatorial) regions, where NPP is also high Soils: highest amounts stored in northern regions, where NPP is low (carbon isn't being used) highest in soil in areas of permafrost where carbon is stores in a cold environment

global carbon cycle

how carbon moves through the earth system most carbon resided in the geosphere in rocks and minerals, next largest site in the oceans more carbon goes into the ocean than leaves the ocean becomes a reservoir for carbon through diffusion

short term organic carbon cycle

interaction between the atmosphere and the biosphere: terrestrial (land) and marine (ocean) components CO2 from the biosphere to the atmosphere through respiration from atmosphere to biosphere through photosynthesis, average biosphere productivity = 0 involves organic matter

What factors led to the peak in the burial of organic matter during the Carboniferous period (250-450 million years ago)?

large peak in burial of organic carbon giving rise to vast majority of fossil fuels, emergence of terrestrial/ land plants, prior to this period no terrestrial plants oxygen spikes at the end of the carboniferous period appearance of terrestrial ecosystems and no susbtance to decompose them; increased burial of organic carbon

three layers of oceanic crust

layer 1= consists of sediment layer 2= pillow basalt layer 3= consists of vertical dikes overlying gabbro below layer 3 is the upper mantle

CaCo3 (calcium carbonate)

limestone, forms in the ocean, utilized by plankton in the water, create shells of organisms and is deposited when becomes bioclastic sedimentary rocks on the ocean floor

oxygen cycle

oxygen and carbon are linked (photolysis and photosynthesis put O2 back into the atmosphere) cycle whereby natural processes and human activity consume atmospheric oxygen and produce carbon dioxide and the Earth's forests and other flora, through photosynthesis, consume carbon dioxide and produce oxygen

role of respiration into the oxygen

oxygen out of the atmosphere animals consume oxygen when undergoing respiration

What processes have been responsible for the rise in atmospheric concentrations of oxygen (O2) over the past 2 billion years?

photolysis and photosynthesis oxygen spiked at the end of the carboniferous period O2 from H20 in the atmosphere goes to the lithosphere via oxidation of rocks and minerals O2 is released by oceans as a by product of photosynthesis

processes controlling exchanges of carbon between terrestrial ecosystems and atmosphere

photosynthesis and respiration and decomposition photosynthesis takes in carbon, respiration, and decomposition; releases it back to the atmosphere

Processes controlling exchanges of carbon between oceans and atmosphere

photosynthesis and respiration occur at top layers of ocean, while decomposition acts on bottom layer CO2 brought to surface through upwelling and released into atmosphere through diffusion colder water can hold more dissolved oxygen, warmer waters will move more CO2 into the atmosphere while colder waters will take more CO2

role of photosynthesis in the oxygen cycle

plants release oxygen into the atmosphere when undergoing photosynthesis

What is the source of fossil fuels?

process of long term storage of organic matter into organic sedimentary rocks (lithified remains of plants or animals) when burned it releases energy

photolysis

process that involves high energy sunlight breaking apart oxygen bearing molecules to produce free oxygen

CaSiO3 (calcium silicate)

rocks that provide the calcium to combine with carbonate to create limestone

75

roughly ____% of the carbon in the atmosphere has found its way into deposits of calcium carbonate (limestone) deposits which constitute by far the largest reservoir in the carbon cycle

H2CO3

weather calcium silicate rocks, releases calcium

Chemical weathering as a mechanism for the exchange of carbon between the atmosphere and geosphere. role of CaCO3 (calcium carbonate)

when carbon dissolves in water, it forms carbonic acid, which is used to weather rocks, yielding bicarbonate ions the bicarbonate ion enters ocean through fresh water systems and in the ocean, the biocarbonate ion combines w/ a calcium ion to form CaCO3, used by marine organisms to form shells when those organisms die, their remains will be brought to the surface of water through upwelling