The atmosphere contains two main forms of carbon: carbon dioxide (CO2) and methane (CH4) both absorb and retain heat intensifying the greenhouse effect. CO2 is more important greenhouse gas because methane is more short-lived and its concentration is much lower. Plant respiration produces CO2, which falls in raindrops and reacts with the atmosphere’s water forming carbonic acid (H2CO3). This acidifies rocks and increases the ocean acidity, which affects ocean biosystems and slows the biological precipitation of CaCO3. By burning fossil fuels and manufacturing concrete humans increase the amount of carbon in the atmosphere, mostly as CO2.
Taylor Royal “Carbon”
Carbon Monoxide
Carbon monoxide (CO) has no color, odor, or taste, and is slightly lighter than air. Atoms of carbon and oxygen are connected by a triple bond. However when in air, carbon monoxide combines with oxygen and forms carbon dioxide CO2 and ozone O3; it is part of photochemical smog and also increases ground ozone level according to reaction CO + 2O2 > CO2 + O3. It occurs naturally in the lowest parts of atmosphere due to photochemical reactions that produce about 5 x 1012 kilograms per year; daytime concentration in atmosphere is twice more during a day than in darkness (Weinstock & Niki, 1972). It is dissolved in molten volcanic rock at high pressures in the Earth’s mantle. It is also present in forest fires, man-made fires, and other forms of combustion associated with vehicles, generators (many of cases occurring during power outages due to severe weather), furnaces, ranges, fireplaces, water heaters, room heaters, or mowers. It is also temporary pollutant in some urban areas. Carbon monoxide forms due to incomplete burning of wood, coal, charcoal, oil, paraffin, propane, natural gas, and trash, when there is not enough oxygen to produce CO2.
CO normal level in human blood is 0% to 3% and is higher in smokers. In higher concentrations it is toxic to humans and animals because it combines with hemoglobin (protein that transports oxygen in blood of vertebrates) to produce carboxy-hemoglobin, which cannot deliver oxygen to tissues and also to myoglobin (a red protein in muscle cells that delivers and stories oxygen) and mitochondrial enzyme cytochrome oxidase. Therefore there is a danger of poisoning when coal is burning in a stove or a car is idling in a closed garage. On average, about 170 people in the United States die every year from CO produced by non-automotive consumer products (U.S. Consumer Product Safety Commision, 2012). Previously, coal gas containing CO was used for domestic lighting, cooking, and heating, and now iron smelting in steel plants still produces CO as a byproduct, blast-furnace gas, which is flammable and toxic (Ayres & Ayres, 2010, p. 36). Some microorganisms (bacteria and archea) living in extreme conditions can metabolize carbon monoxide.
Carbon monoxide is produced in organism as part of normal metabolism (when produced during hemoglobin breakdown) and may possibly have biological functions as a biological regulator of several functions: as a vascular growth factor, anti-inflammatory agent, and blood vessel relaxant. CO is associated with many functions in the immune, respiratory, reproductive, gastrointestinal, kidney, and liver systems. According to Wu & Wang (2005), communication inside a cell and also among cells occurs by conducting mechanical, electrical, or chemical signals. Chemical communication includes hormones (acting on distant targets via circulation in endocrine mode), autocoids (that act on the same cells from which they are produced (such as prostaglandins, adenosine, and platelet-activating factor), and transmitters (regulation for adjacent cells or cells where transmitters are produced).
Cayden Osley “Carbon Limerick”
Physiological functions of CO involve acting as a signaling molecule in the neuronal system: neuronal activities such as regulation of neurotransmitters (ACH, catecholamines, serotonin, histamine, glutamate, glycine, GABA, and ATP or its metabolites), neuropeptide release, learning and memory, and odor response adaptation. Abnormalities in CO metabolism have been linked to a variety of diseases including neuro degenerations, hypertension, heart failure, and inflammation (Wu & Wang, 2005).
Solomon Snyder & Christopher Ferris (2000) examined carbon monoxide CO, nitrogen monoxide (nitric oxide) NO and d-serine as candidate neurotransmitters and offered insights regarding novel definitions of neurotransmitters or neuromodulators. As described by the authors, a transmitter is a molecule, released by neurons or glial cells (non-neuronal, connective cells that support and protect neurons) that physiologically influences the eletrochemical state of adjacent cells. Outside the CNS, those adjacent target cells need not be neurons and, in most instances, would be smooth muscle or glandular cells (Snyder & Ferris, 2000, p. 1750). Carbon monoxide (CO), nitric oxide (NO), and hydrogen sulfide (H2S) display metabolism and physiological functions that position this gas in the family of endogenous (originating within an organism) signaling gasotransmitters (Wang, 2002).
Industrial carbon monoxide’s production includes many methods for obtaining CO under different names. A producer gas, a low-grade fuel containing nitrogen and carbon monoxide, forms during passing air or air-and-steam through red-hot carbon. Water gas, a fuel gas consisting mainly carbon monoxide and hydrogen, forms during passing steam over incandescent, white-hot coke. Synthesis gas, a mixture of hydrogen, carbon monoxide, and sometimes also carbon dioxide, serves for producing synthetic chemicals such as ammonia or methanol that are used for making feedstock – raw material for manufacturing industrial, chemical, or pharmaceutical products. Several laboratory methods also allow obtaining carbon monoxide. As an industrial gas, it has many other applications in bulk chemicals manufacturing, for example, for producing fuels used as replacement for petrol, or as color additive in meat and fish packaging, to keep them looking fresh (because it combines with myoglobin – oxygen carrying and storing red pigment, a protein similar to hemoglobin, present in muscle tissues).
The consumption of fossil fuels results in energy-related carbon dioxide (CO2) emissions. The U.S. carbon dioxide emissions resulting from the consumption of fossil fuels were 5,471 million metric tons CO2 in 2011. It fell 2.4 percent from the 2010 level and, according to the EIA predictions will be below the 2005 level through the year 2035 (EIA, 2012a; EIA, 2012b).
Greenhouse gases in an atmosphere trap heat from the sun and warm the planet’s surface. They are mostly water vapor (H2O), carbon dioxide (CO2), methane (CH4), ozone (O3), and nitrous oxide (N2O). Nitrogen (N2 comprising 78% of the dry atmosphere) and oxygen (O2 comprising 21%) exert almost no greenhouse effect (IPPC, 2007). Most of the U.S. greenhouse gas emissions are related to energy consumption, and most of those are CO2. From 1990 to 2011, energy-related CO2 emissions in the United States increased by about 0.4% per year, and comprised about 18% of the world’s total energy-related CO2. Greenhouse gases absorb and emit thermal infrared radiation (with longer wavelength than that of visible light). The greenhouse effect results from this: absorption and re-radiation of heat toward the Earth surface and lower atmosphere, and the following elevation of the Earth temperature. In the United States, about three-quarters of human-caused greenhouse gas emissions came from the burning of fossil fuels in energy use driven by economic growth, heating and cooling needs, and electricity generation. Energy consumption causes 87% of the U.S. greenhouse gas emission, which is growing by about 1% per year. Levels of greenhouse gases have increased by about 40% since industrialization began around 150 years ago. A cap-and-trade program (which increases the costs of using fossil fuels) places a limit (or cap) on the total amount of emissions, to reduce polluting emissions through a system of allowances that can be traded to minimize costs to affected sources.
The Fast and Slow Carbon Cycles
Scientists describe the fast and slow carbon cycle.
The Fast Carbon Cycle
Processes going in the carbon cycle regulate the CO2 concentrationin the atmosphere in a natural way. Carbon geochemical cycle describes the processes that sustain life on Earth. It is generally accepted that the rising levels of CO2 concentration (from 280 ppm in 1800 to almost 400 ppm; ppm, a measure of concentration, means ‘part(s) per million’)result in global warming, so lowering the amount of CO2 in the atmosphere may re-balance the carbon cycle (NASA Earth Observatory, 2011).
The fast carbon cycle includes the plants and phytoplankton (microscopic organisms in the ocean); they are the main components of the fast, biological/physical carbon cycle, which operates at the time scale of days to thousands of years. The fast carbon cycle presents the movement of carbon through life forms or the biosphere such as animal tissues, between land, atmosphere, and oceans, in billions of tons of carbon per year (with diurnal and seasonal oscillations). It is caused both by natural fluxes and human actions.
The Slow Carbon Cycle
The geological component of the carbon cycle operates at a slow pace, at the time scale of millions of years, yet it determines the amount of carbon in the atmosphere, and thus of global temperature. Tectonic activity, that may last hundreds of millions years, moves great amounts of carbon (10-100 million metric tons every year) between rocks, soil, ocean, and atmosphere. There is carbon stored in lithosphere as rocks from the time when the earth was formed, and the organic carbon, mostly as limestone and its derivatives resulting from the sedimentation of CaCO3 stored in the shells of marine shell-building (calcifying) organisms (such as corals) and plankton (like coccolithophores and foraminifera), which sink after death to the seafloor. Calcium ions combine with carbonic acid into calcium carbonate that becomes limestone or its metamorphic form, marble. There are also fossilized organic materials sedimented and buried under high heat and pressure, some fossils aging millions, sometimes hundreds of millions of years. Carbon moves with rain from the atmosphere to the lithosphere as carbonic acid (H2CO3) and causes chemical weathering: calcium, magnesium, potassium, or sodium ions flow in rivers to the ocean.
Humans strongly alter the carbon cycle, mostly through CO2 emissions into the atmosphere that are exceeding natural fluctuations (Falkowski et al., 2000), altering weather patterns, influencing oceanic chemistry, and affecting global climate, especially temperature. The use of fossil fuels has accelerated since the industrial revolution and increased carbon accumulation in the atmosphere.
Scientists estimate there is organic matter beneath the Antarctic Ice Sheet, up to 14 kilometers thick and weighting billions of tons, possibly the same order of magnitude as in the Arctic permafrost. It contains metabolically active Archaea (single-cell microorganisms) that support the degradation of organic carbon to methane. That means organic carbon is probably being metabolized beneath the ice by microbes to carbon dioxide and methane gas. It may play a part in the global climate warming because of the ice-sheet deterioration (Wadham et al., 2012).
About 100 million tons of carbon dioxide is liberated daily into the air from oil and coal by combustion. The gas traps heat in the atmosphere. Half of the carbon dioxide stays up there and then dissolves into the oceans; the other half falls back to earth: some is taken up by growing plants, one-quarter of carbon released through fossil fuel emissions is disappearing.
NASA is launching a satellite, the Orbiting Carbon Observatory-2 to help solve the puzzle. Passing over the North and South Poles at an altitude of 438 miles, it will observe the same spots every 16 days as the earth rotates beneath. These repeated measurements will allow scientists to observe the rise and fall of carbon dioxide with the seasons and figure out how the balance changes with droughts or floods. It is unknown how plants have kept pace with fossil fuel emissions that have nearly tripled since 1960; there is no new rain forest.
The orbiting observatory carries a single instrument, to measure colors of sunlight bouncing off the earth. The relative intensity of the colors will tell how much carbon dioxide the light beam passed through, and the spacecraft will take a million measurements a day. Because of intervening clouds, only a tenth of the measurements — about 100,000 a day — will prove useful data. A Japanese satellite is making similar measurements, but with less precision.
Levels of carbon dioxide in the air have jumped 40 percent since the start of the Industrial Revolution, but the amount is still tiny: of every million molecules of air, just 400 are carbon dioxide. Over a power plant or a city where emissions are higher, that number rises by perhaps one molecule per million. A field of corn stalks at the height of growing season might reduce the number by a similar amount. The instrument may also be able to discern a faint infrared fluorescent glow emitted by plants as they photosynthesize, which could indicate their health. Michael Freilich, director of the earth sciences division, said, “There is no question that the Obama administration puts a very high priority on understanding the earth.”