A report on Carbon dioxide

Crystal structure of dry ice
Stretching and bending oscillations of the CO2 carbon dioxide molecule. Upper left: symmetric stretching. Upper right: antisymmetric stretching. Lower line: degenerate pair of bending modes.
Pellets of "dry ice", a common form of solid carbon dioxide
Pressure–temperature phase diagram of carbon dioxide. Note that it is a log-lin chart.
Carbon dioxide bubbles in a soft drink
Dry ice used to preserve grapes after harvest
Use of a CO2 fire extinguisher
Comparison of the pressure–temperature phase diagrams of carbon dioxide (red) and water (blue) as a log-lin chart with phase transitions points at 1 atmosphere
A carbon-dioxide laser
Keeling curve of the atmospheric CO2 concentration
Atmospheric CO2 annual growth rose 300% since the 1960s.
Annual flows from anthropogenic sources (left) into Earth's atmosphere, land, and ocean sinks (right) since the 1960s. Units in equivalent gigatonnes carbon per year.
Pterapod shell dissolved in seawater adjusted to an ocean chemistry projected for the year 2100.
Overview of the Calvin cycle and carbon fixation
Overview of photosynthesis and respiration. Carbon dioxide (at right), together with water, form oxygen and organic compounds (at left) by photosynthesis, which can be respired  to water and (CO2).
Symptoms of carbon dioxide toxicity, by increasing volume percent in air.
Rising levels of CO2 threatened the Apollo 13 astronauts who had to adapt cartridges from the command module to supply the carbon dioxide scrubber in the Lunar Module, which they used as a lifeboat.
CO2 concentration meter using a nondispersive infrared sensor

Chemical compound made up of molecules that each have one carbon atom covalently double bonded to two oxygen atoms.

- Carbon dioxide
Crystal structure of dry ice

156 related topics with Alpha

Overall

Schematic of photosynthesis in plants. The carbohydrates produced are stored in or used by the plant.

Photosynthesis

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Process used by plants and other organisms to convert light energy into chemical energy that, through cellular respiration, can later be released to fuel the organism's activities.

Process used by plants and other organisms to convert light energy into chemical energy that, through cellular respiration, can later be released to fuel the organism's activities.

Schematic of photosynthesis in plants. The carbohydrates produced are stored in or used by the plant.
Composite image showing the global distribution of photosynthesis, including both oceanic phytoplankton and terrestrial vegetation. Dark red and blue-green indicate regions of high photosynthetic activity in the ocean and on land, respectively.
Photosynthesis changes sunlight into chemical energy, splits water to liberate O2, and fixes CO2 into sugar.
Light-dependent reactions of photosynthesis at the thylakoid membrane
The "Z scheme"
Overview of the Calvin cycle and carbon fixation
Overview of C4 carbon fixation
Plant cells with visible chloroplasts (from a moss, Plagiomnium affine)
Portrait of Jan Baptist van Helmont by Mary Beale, c.1674
Melvin Calvin works in his photosynthesis laboratory.
The leaf is the primary site of photosynthesis in plants.
Absorbance spectra of free chlorophyll a ( blue ) and b ( red ) in a solvent. The action spectra of chlorophyll molecules are slightly modified in vivo depending on specific pigment–protein interactions.
Photorespiration

Some of this chemical energy is stored in carbohydrate molecules, such as sugars and starches, which are synthesized from carbon dioxide and water – hence the name photosynthesis, from the Greek phōs (φῶς), "light", and synthesis (σύνθεσις), "putting together".

Joseph Priestley is usually given priority in the discovery.

Oxygen

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Chemical element with the symbol O and atomic number 8.

Chemical element with the symbol O and atomic number 8.

Joseph Priestley is usually given priority in the discovery.
Antoine Lavoisier discredited the phlogiston theory.
Robert H. Goddard and a liquid oxygen-gasoline rocket
An experiment setup for preparation of oxygen in academic laboratories
Orbital diagram, after Barrett (2002), showing the participating atomic orbitals from each oxygen atom, the molecular orbitals that result from their overlap, and the aufbau filling of the orbitals with the 12 electrons, 6 from each O atom, beginning from the lowest-energy orbitals, and resulting in covalent double-bond character from filled orbitals (and cancellation of the contributions of the pairs of σ and σ* and π and π* orbital pairs).
Liquid oxygen, temporarily suspended in a magnet owing to its paramagnetism
Space-filling model representation of dioxygen (O2) molecule
Oxygen discharge (spectrum) tube
Late in a massive star's life, 16O concentrates in the O-shell, 17O in the H-shell and 18O in the He-shell.
Cold water holds more dissolved.
500 million years of climate change vs. 18O
Photosynthesis splits water to liberate and fixes into sugar in what is called a Calvin cycle.
build-up in Earth's atmosphere: 1) no produced; 2) produced, but absorbed in oceans & seabed rock; 3)  starts to gas out of the oceans, but is absorbed by land surfaces and formation of ozone layer; 4–5)  sinks filled and the gas accumulates
Hofmann electrolysis apparatus used in electrolysis of water.
Oxygen and MAPP gas compressed-gas cylinders with regulators
An oxygen concentrator in an emphysema patient's house
Low pressure pure is used in space suits.
Most commercially produced is used to smelt and/or decarburize iron.
Water is the most familiar oxygen compound.
Oxides, such as iron oxide or rust, form when oxygen combines with other elements.
Main symptoms of oxygen toxicity
The interior of the Apollo 1 Command Module. Pure at higher than normal pressure and a spark led to a fire and the loss of the Apollo 1 crew.

carbon dioxide + water + sunlight → glucose + dioxygen

Theoretically predicted phase diagram of carbon, from 1989. Newer work indicates that the melting point of diamond (top-right curve) does not go above about 9000 K.

Carbon

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Chemical element with the symbol C and atomic number 6.

Chemical element with the symbol C and atomic number 6.

Theoretically predicted phase diagram of carbon, from 1989. Newer work indicates that the melting point of diamond (top-right curve) does not go above about 9000 K.
A large sample of glassy carbon
Some allotropes of carbon: a) diamond; b) graphite; c) lonsdaleite; d–f) fullerenes (C60, C540, C70); g) amorphous carbon; h) carbon nanotube
Comet C/2014 Q2 (Lovejoy) surrounded by glowing carbon vapor
Graphite ore, shown with a penny for scale
Raw diamond crystal
"Present day" (1990s) sea surface dissolved inorganic carbon concentration (from the GLODAP climatology)
Diagram of the carbon cycle. The black numbers indicate how much carbon is stored in various reservoirs, in billions tonnes ("GtC" stands for gigatonnes of carbon; figures are circa 2004). The purple numbers indicate how much carbon moves between reservoirs each year. The sediments, as defined in this diagram, do not include the ≈70 million GtC of carbonate rock and kerogen.
Structural formula of methane, the simplest possible organic compound.
Correlation between the carbon cycle and formation of organic compounds. In plants, carbon dioxide formed by carbon fixation can join with water in photosynthesis ( green ) to form organic compounds, which can be used and further converted by both plants and animals.
This anthracene derivative contains a carbon atom with 5 formal electron pairs around it.
Antoine Lavoisier in his youth
Carl Wilhelm Scheele
Diamond output in 2005
Pencil leads for mechanical pencils are made of graphite (often mixed with a clay or synthetic binder).
Sticks of vine and compressed charcoal
A cloth of woven carbon fibres
Silicon carbide single crystal
The C60 fullerene in crystalline form
Tungsten carbide endmills
Worker at carbon black plant in Sunray, Texas (photo by John Vachon, 1942)

The largest sources of inorganic carbon are limestones, dolomites and carbon dioxide, but significant quantities occur in organic deposits of coal, peat, oil, and methane clathrates.

Average surface air temperatures from 2011 to 2021 compared to the 1956–1976 average

Climate change

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Contemporary climate change includes both global warming and its impacts on Earth's weather patterns.

Contemporary climate change includes both global warming and its impacts on Earth's weather patterns.

Average surface air temperatures from 2011 to 2021 compared to the 1956–1976 average
Change in average surface air temperature since the industrial revolution, plus drivers for that change. Human activity has caused increased temperatures, with natural forces adding some variability.
Global surface temperature reconstruction over the last 2000 years using proxy data from tree rings, corals, and ice cores in blue. Directly observed data is in red.
Drivers of climate change from 1850–1900 to 2010–2019. There was no significant contribution from internal variability or solar and volcanic drivers.
concentrations over the last 800,000 years as measured from ice cores (blue/green) and directly (black)
The Global Carbon Project shows how additions to since 1880 have been caused by different sources ramping up one after another.
The rate of global tree cover loss has approximately doubled since 2001, to an annual loss approaching an area the size of Italy.
Sea ice reflects 50% to 70% of incoming solar radiation while the dark ocean surface only reflects 6%, so melting sea ice is a self-reinforcing feedback.
Projected global surface temperature changes relative to 1850–1900, based on CMIP6 multi-model mean changes.
The sixth IPCC Assessment Report projects changes in average soil moisture that can disrupt agriculture and ecosystems. A reduction in soil moisture by one standard deviation means that average soil moisture will approximately match the ninth driest year between 1850 and 1900 at that location.
Historical sea level reconstruction and projections up to 2100 published in 2017 by the U.S. Global Change Research Program
The IPCC Sixth Assessment Report (2021) projects that extreme weather will be progressively more common as the Earth warms.
Scenarios of global greenhouse gas emissions. If all countries achieve their current Paris Agreement pledges, average warming by 2100 would still significantly exceed the maximum 2 °C target set by the Agreement.
Coal, oil, and natural gas remain the primary global energy sources even as renewables have begun rapidly increasing.
Economic sectors with more greenhouse gas contributions have a greater stake in climate change policies.
Most emissions have been absorbed by carbon sinks, including plant growth, soil uptake, and ocean uptake (2020 Global Carbon Budget).
Since 2000, rising emissions in China and the rest of world have surpassed the output of the United States and Europe.
Per person, the United States generates at a far faster rate than other primary regions.
Academic studies of scientific consensus reflect that the level of consensus correlates with expertise in climate science.
Data has been cherry picked from short periods to falsely assert that global temperatures are not rising. Blue trendlines show short periods that mask longer-term warming trends (red trendlines). Blue dots show the so-called global warming hiatus.
The 2017 People's Climate March took place in hundreds of locations. Shown: the Washington, D.C. march, protesting policies of then-U.S. President Trump.
Tyndall's ratio spectrophotometer (drawing from 1861) measured how much infrared radiation was absorbed and emitted by various gases filling its central tube.
alt=Underwater photograph of branching coral that is bleached white|Ecological collapse. Bleaching has damaged the Great Barrier Reef and threatens reefs worldwide.<ref>{{Cite web|url=https://sos.noaa.gov/datasets/coral-reef-risk-outlook/|title=Coral Reef Risk Outlook|access-date=4 April 2020|publisher=National Oceanic and Atmospheric Administration|quote=At present, local human activities, coupled with past thermal stress, threaten an estimated 75 percent of the world's reefs. By 2030, estimates predict more than 90% of the world's reefs will be threatened by local human activities, warming, and acidification, with nearly 60% facing high, very high, or critical threat levels.}}</ref>
alt=Photograph of evening in a valley settlement. The skyline in the hills beyond is lit up red from the fires.|Extreme weather. Drought and high temperatures worsened the 2020 bushfires in Australia.<ref>{{harvnb|Carbon Brief, 7 January|2020}}.</ref>
alt=The green landscape is interrupted by a huge muddy scar where the ground has subsided.|Arctic warming. Permafrost thaws undermine infrastructure and release methane, a greenhouse gas.
alt=An emaciated polar bear stands atop the remains of a melting ice floe.|Habitat destruction. Many arctic animals rely on sea ice, which has been disappearing in a warming Arctic.<ref>{{harvnb|IPCC AR5 WG2 Ch28|2014|p=1596|ps=: "Within 50 to 70 years, loss of hunting habitats may lead to elimination of polar bears from seasonally ice-covered areas, where two-thirds of their world population currently live."}}</ref>
alt=Photograph of a large area of forest. The green trees are interspersed with large patches of damaged or dead trees turning purple-brown and light red.|Pest propagation. Mild winters allow more pine beetles to survive to kill large swaths of forest.<ref>{{Cite web|url=https://www.nps.gov/romo/learn/nature/climatechange.htm|title=What a changing climate means for Rocky Mountain National Park|publisher=National Park Service|access-date=9 April 2020}}</ref>
Environmental migration. Sparser rainfall leads to desertification that harms agriculture and can displace populations. Shown: Telly, Mali (2008).<ref>{{harvnb|Serdeczny|Adams|Baarsch|Coumou|2016}}.</ref>
Agricultural changes. Droughts, rising temperatures, and extreme weather negatively impact agriculture. Shown: Texas, US (2013).<ref>{{harvnb|IPCC SRCCL Ch5|2019|pp=439, 464}}.</ref>
Tidal flooding. Sea-level rise increases flooding in low-lying coastal regions. Shown: Venice, Italy (2004).<ref name="NOAAnuisance">{{cite web|url=http://oceanservice.noaa.gov/facts/nuisance-flooding.html |title=What is nuisance flooding? |author=National Oceanic and Atmospheric Administration |access-date=April 8, 2020}}</ref>
Storm intensification. Bangladesh after Cyclone Sidr (2007) is an example of catastrophic flooding from increased rainfall.<ref>{{harvnb|Kabir|Khan|Ball|Caldwell|2016}}.</ref>
Heat wave intensification. Events like the June 2019 European heat wave are becoming more common.<ref>{{harvnb|Van Oldenborgh|Philip|Kew|Vautard|2019}}.</ref>

Instead, they are caused by the emission of greenhouse gases, mostly carbon dioxide and methane.

Daniel Rutherford, discoverer of nitrogen

Nitrogen

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Chemical element with the symbol N and atomic number 7.

Chemical element with the symbol N and atomic number 7.

Daniel Rutherford, discoverer of nitrogen
The shapes of the five orbitals occupied in nitrogen. The two colours show the phase or sign of the wave function in each region. From left to right: 1s, 2s (cutaway to show internal structure), 2px, 2py, 2pz.
Table of nuclides (Segrè chart) from carbon to fluorine (including nitrogen). Orange indicates proton emission (nuclides outside the proton drip line); pink for positron emission (inverse beta decay); black for stable nuclides; blue for electron emission (beta decay); and violet for neutron emission (nuclides outside the neutron drip line). Proton number increases going up the vertical axis and neutron number going to the right on the horizontal axis.
Molecular orbital diagram of dinitrogen molecule, N2. There are five bonding orbitals and two antibonding orbitals (marked with an asterisk; orbitals involving the inner 1s electrons not shown), giving a total bond order of three.
Solid nitrogen on the plains of Sputnik Planitia on Pluto next to water ice mountains
Structure of [Ru(NH3)5(N2)]2+ (pentaamine(dinitrogen)ruthenium(II)), the first dinitrogen complex to be discovered
Mesomeric structures of borazine, (–BH–NH–)3
Standard reduction potentials for nitrogen-containing species. Top diagram shows potentials at pH 0; bottom diagram shows potentials at pH 14.
Nitrogen trichloride
Nitrogen dioxide at −196 °C, 0 °C, 23 °C, 35 °C, and 50 °C. converts to colourless dinitrogen tetroxide at low temperatures, and reverts to  at higher temperatures.
Fuming nitric acid contaminated with yellow nitrogen dioxide
Schematic representation of the flow of nitrogen compounds through a land environment
A container vehicle carrying liquid nitrogen.

Free nitrogen atoms easily react with most elements to form nitrides, and even when two free nitrogen atoms collide to produce an excited N2 molecule, they may release so much energy on collision with even such stable molecules as carbon dioxide and water to cause homolytic fission into radicals such as CO and O or OH and H. Atomic nitrogen is prepared by passing an electric discharge through nitrogen gas at 0.1–2 mmHg, which produces atomic nitrogen along with a peach-yellow emission that fades slowly as an afterglow for several minutes even after the discharge terminates.

Estimated change in seawater pH caused by human-created carbon dioxide between the 1700s and the 1990s, from the Global Ocean Data Analysis Project (GLODAP) and the World Ocean Atlas

Ocean acidification

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Estimated change in seawater pH caused by human-created carbon dioxide between the 1700s and the 1990s, from the Global Ocean Data Analysis Project (GLODAP) and the World Ocean Atlas
Here is a detailed image of the full carbon cycle
NOAA provides evidence for the upwelling of "acidified" water onto the Continental Shelf. In the figure above, note the vertical sections of (A) temperature, (B) aragonite saturation, (C) pH, (D) DIC, and (E) p on transect line 5 off Pt. St. George, California. The potential density surfaces are superimposed on the temperature section. The 26.2 potential density surface delineates the location of the first instance in which the undersaturated water is upwelled from depths of 150 to 200 m onto the shelf and outcropping at the surface near the coast. The red dots represent sample locations.
Ocean Acidification Infographic
The cycle between the atmosphere and the ocean
Distribution of (A) aragonite and (B) calcite saturation depth in the global oceans
This map shows changes in the aragonite saturation level of ocean surface waters between the 1880s and the most recent decade (2006–2015). Aragonite is a form of calcium carbonate that many marine animals use to build their skeletons and shells. The lower the saturation level, the more difficult it is for organisms to build and maintain their skeletons and shells. A negative change represents a decrease in saturation.
Here is detailed diagram of the carbon cycle within the ocean
Bjerrum plot: Change in carbonate system of seawater from ocean acidification.
Shells of pteropods dissolve in increasingly acidic conditions caused by increased amounts of atmospheric
A normally-protective shell made thin, fragile and transparent by acidification
Drivers of hypoxia and ocean acidification intensification in upwelling shelf systems. Equatorward winds drive the upwelling of low dissolved oxygen (DO), high nutrient, and high dissolved inorganic carbon (DIC) water from above the oxygen minimum zone. Cross-shelf gradients in productivity and bottom water residence times drive the strength of DO (DIC) decrease (increase) as water transits across a productive continental shelf.
Demonstrator calling for action against ocean acidification at the People's Climate March (2017).
Ocean acidification: mean seawater pH. Mean seawater pH is shown based on in-situ measurements of pH from the Aloha station.
"Present day" (1990s) sea surface pH
Present day alkalinity
"Present day" (1990s) sea surface anthropogenic {{chem|CO|2}}
Vertical inventory of "present day" (1990s) anthropogenic {{chem|CO|2}}
Change in surface {{chem|CO|3|2-}} ion from the 1700s to the 1990s
Present day DIC
Pre-Industrial DIC
A NOAA (AOML) in situ {{chem|CO|2}} concentration sensor (SAMI-CO2), attached to a Coral Reef Early Warning System station, utilized in conducting ocean acidification studies near coral reef areas
A NOAA (PMEL) moored autonomous {{chem|CO|2}} buoy used for measuring {{chem|CO|2}} concentration and ocean acidification studies

Ocean acidification is the ongoing decrease in the pH value of the Earth's oceans, caused by the uptake of carbon dioxide from the atmosphere.

The greenhouse effect of solar radiation on the Earth's surface caused by emission of greenhouse gases.

Greenhouse gas

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Gas that absorbs and emits radiant energy within the thermal infrared range, causing the greenhouse effect.

Gas that absorbs and emits radiant energy within the thermal infrared range, causing the greenhouse effect.

The greenhouse effect of solar radiation on the Earth's surface caused by emission of greenhouse gases.
Radiative forcing (warming influence) of different contributors to climate change through 2019, as reported in the Sixth IPCC assessment report.
Atmospheric absorption and scattering at different wavelengths of electromagnetic waves. The largest absorption band of carbon dioxide is not far from the maximum in the thermal emission from ground, and it partly closes the window of transparency of water; hence its major effect.
Concentrations of carbon monoxide in the Spring and Fall of 2000 in the lower atmosphere showing a range from about 390 parts per billion (dark brown pixels), to 220 parts per billion (red pixels), to 50 parts per billion (blue pixels).
Increasing water vapor in the stratosphere at Boulder, Colorado
Schmidt et al. (2010) analysed how individual components of the atmosphere contribute to the total greenhouse effect. They estimated that water vapor accounts for about 50% of Earth's greenhouse effect, with clouds contributing 25%, carbon dioxide 20%, and the minor greenhouse gases and aerosols accounting for the remaining 5%. In the study, the reference model atmosphere is for 1980 conditions. Image credit: NASA.
The radiative forcing (warming influence) of long-lived atmospheric greenhouse gases has accelerated, almost doubling in 40 years.
Top: Increasing atmospheric carbon dioxide levels as measured in the atmosphere and reflected in ice cores. Bottom: The amount of net carbon increase in the atmosphere, compared to carbon emissions from burning fossil fuel.
400,000 years of ice core data
Recent year-to-year increase of atmospheric.
Major greenhouse gas trends.
The US, China and Russia have cumulatively contributed the greatest amounts of since 1850.

The primary greenhouse gases in Earth's atmosphere are water vapor, carbon dioxide , methane , nitrous oxide , and ozone.

Coal

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Combustible black or brownish-black sedimentary rock, formed as rock strata called coal seams.

Combustible black or brownish-black sedimentary rock, formed as rock strata called coal seams.

Example chemical structure of coal
Coastal exposure of the Point Aconi Seam in Nova Scotia
Coal ranking system used by the United States Geological Survey
Chinese coal miners in an illustration of the Tiangong Kaiwu encyclopedia, published in 1637
Coal miner in Britain, 1942
Coke oven at a smokeless fuel plant in Wales, United Kingdom
Production of chemicals from coal
Castle Gate Power Plant near Helper, Utah, US
Coal rail cars
Bulldozer pushing coal in Ljubljana Power Station, Slovenia
Extensive coal docks seen in Toledo, Ohio, 1895
Coal production by region
Aerial photograph of the site of the Kingston Fossil Plant coal fly ash slurry spill taken the day after the event
Protesting damage to the Great Barrier Reef caused by climate change in Australia
Tree houses for protesting the felling of part of Hambach Forest for the Hambach surface mine in Germany: after which the felling was suspended in 2018
A coal mine in Wyoming, United States. The United States has the world's largest coal reserves.

The use of coal damages the environment, and it is the largest anthropogenic source of carbon dioxide contributing to climate change.

concentrations over the last 800,000 years

Carbon dioxide in Earth's atmosphere

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concentrations over the last 800,000 years
Between 1850 and 2019 the Global Carbon Project estimates that about 2/3rds of excess carbon dioxide emissions have been caused by burning fossil fuels, and a little less than half of that has stayed in the atmosphere.
2011 carbon dioxide mole fraction in the troposphere
The Keeling Curve of atmospheric concentrations measured at Mauna Loa Observatory
Concentration of atmospheric over the last 40,000 years, from the Last Glacial Maximum to the present day. The current rate of increase is much higher than at any point during the last deglaciation.
Graph of CO2 (green), reconstructed temperature (blue) and dust (red) from the Vostok ice core for the past 420,000 years
Correspondence between temperature and atmospheric during the last 800,000 years
A pictogram of the greenhouse effect
Radiative forcing drivers of climate change in year 2011, relative to pre-industrial (1750).
This diagram of the fast carbon cycle shows the movement of carbon between land, atmosphere, and oceans in billions of metric tons of carbon per year. Yellow numbers are natural fluxes, red are human contributions, white are stored carbon.
Annual flows from anthropogenic sources (left) into Earth's atmosphere, land, and ocean sinks (right) since year 1960. Units in equivalent gigatonnes carbon per year.
Photosynthesis changes sunlight into chemical energy, splits water to liberate O2, and fixes CO2 into sugar.
Air-sea exchange of
The US, China and Russia have cumulatively contributed the greatest amounts of since 1850.
CO2 in Earth's atmosphere if half of anthropogenic CO2 emissions are not absorbed. (NASA computer simulation)
Carbon Dioxide observations from 2005 to 2014 showing the seasonal variations and the difference between northern and southern hemispheres
Global fossil carbon emissions 1800–2014
False-color image of smoke and ozone pollution from Indonesian fires, 1997
Biosphere {{CO2}} flux in the northern hemisphere winter (NOAA Carbon Tracker)
Biosphere {{CO2}} flux in the northern hemisphere summer (NOAA Carbon Tracker)

Carbon dioxide is an important trace gas in Earth's atmosphere.

Cyanobacteria

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Cyanobacteria, also known as Cyanophyta, are a phylum of Gram-negative bacteria that obtain energy via photosynthesis.

Cyanobacteria, also known as Cyanophyta, are a phylum of Gram-negative bacteria that obtain energy via photosynthesis.

Cyanobacteria are found almost everywhere. Sea spray containing marine microorganisms, including cyanobacteria, can be swept high into the atmosphere where they become aeroplankton, and can travel the globe before falling back to earth.
• Unicellular: (a) Synechocystis and (b) Synechococcus elongatus
• Non-heterocytous: (c) Arthrospira maxima,• False- or non-branching heterocytous: (f) Nostoc• True-branching heterocytous: (h) Stigonema
Outer and plasma membranes are in blue, thylakoid membranes in gold, glycogen granules in cyan, carboxysomes (C) in green, and a large dense polyphosphate granule (G) in pink
Environmental impact of cyanobacteria and other photosynthetic microorganisms in aquatic systems. Different classes of photosynthetic microorganisms are found in aquatic and marine environments where they form the base of healthy food webs and participate in symbioses with other organisms. However, shifting environmental conditions can result in community dysbiosis, where the growth of opportunistic species can lead to harmful blooms and toxin production with negative consequences to human health, livestock and fish stocks. Positive interactions are indicated by arrows; negative interactions are indicated by closed circles on the ecological model.
Diagnostic Drawing: Cyanobacteria associated with tufa: Microcoleus vaginatus
(1) Cyanobacteria enter the leaf tissue through the stomata and colonize the intercellular space, forming a cyanobacterial loop.
(2) On the root surface, cyanobacteria exhibit two types of colonization pattern; in the root hair, filaments of Anabaena and Nostoc species form loose colonies, and in the restricted zone on the root surface, specific Nostoc species form cyanobacterial colonies.
(3) Co-inoculation with 2,4-D and Nostoc spp. increases para-nodule formation and nitrogen fixation. A large number of Nostoc spp. isolates colonize the root endosphere and form para-nodules.
Live cyanobionts (cyanobacterial symbionts) belonging to Ornithocercus dinoflagellate host consortium
(a) O. magnificus with numerous cyanobionts present in the upper and lower girdle lists (black arrowheads) of the cingulum termed the symbiotic chamber.
(b) O. steinii with numerous cyanobionts inhabiting the symbiotic chamber.
(c) Enlargement of the area in (b) showing two cyanobionts that are being divided by binary transverse fission (white arrows).
Light microscope view of cyanobacteria from a microbial mat
Types of cell death according to the Nomenclature Committee on Cell Death (upper panel; and proposed for cyanobacteria (lower panel). Cells exposed to extreme injury die in an uncontrollable manner, reflecting the loss of structural integrity. This type of cell death is called "accidental cell death" (ACD). “Regulated cell death (RCD)” is encoded by a genetic pathway that can be modulated by genetic or pharmacologic interventions. Programmed cell death (PCD) is a type of RCD that occurs as a developmental program, and has not been addressed in cyanobacteria yet. RN, regulated necrosis.
Synechococcus uses a gliding technique to move at 25 μm/s. Scale bar is about 10 µm.
Based on data: nodes (1–10) and stars representing common ancestors from Sánchez-Baracaldo et al., 2015, timing of the Great Oxidation Event (GOE), the Lomagundi-Jatuli Excursion, and Gunflint formation. Green lines represent freshwater lineages and blue lines represent marine lineages are based on Bayesian inference of character evolution (stochastic character mapping analyses).
Tree of Life in Generelle Morphologie der Organismen (1866). Note the location of the genus
Nostoc with algae and not with bacteria (kingdom "Monera")
Cyanobacteria cultured in specific media: Cyanobacteria can be helpful in agriculture as they have the ability to fix atmospheric nitrogen in soil.
Spirulina tablets
Stromatolites left behind by cyanobacteria are the oldest known fossils of life on Earth. This fossil is one billion years old.
Oncolitic limestone formed from successive layers of calcium carbonate precipitated by cyanobacteria
Oncolites from the Late Devonian Alamo bolide impact in Nevada
{{center|Cyanobacterial remains of an annulated tubular microfossil Oscillatoriopsis longa{{hsp}}<ref>{{cite journal |doi=10.1111/pala.12374 |title=First record of Cyanobacteria in Cambrian Orsten deposits of Sweden |year=2018 |last1=Castellani |first1=Christopher |last2=Maas |first2=Andreas |last3=Eriksson |first3=Mats E. |last4=Haug |first4=Joachim T. |last5=Haug |first5=Carolin |last6=Waloszek |first6=Dieter |journal=Palaeontology |volume=61 |issue=6 |pages=855–880 |s2cid=134049042}}</ref>
Cyanobacteria activity turns Coatepeque Caldera lake a turquoise color
Cyanobacterial bloom near Fiji
Cyanobacteria in Lake Köyliö.

Carbon dioxide is reduced to form carbohydrates via the Calvin cycle.