Query: Ironic' study finds more CO2 has slightly cooled the planet

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Atmosphere of Mars <=SEP=> The atmosphere of Mars is the layer of gases surrounding Mars . It is composed mostly of carbon dioxide . The atmospheric pressure on the Martian surface averages 600 Pa , about 0.6 % of Earth 's mean sea level pressure of 101.3 kPa . It ranges from a low of 30 Pa on Olympus Mons 's peak to over 1155 Pa in the depths of Hellas Planitia . This pressure is well below the Armstrong limit for the unprotected human body . Mars 's atmospheric mass of 25 teratonnes compares to Earth 's 5148 teratonnes with a scale height of about 11 km versus Earth 's 7 km .   The Martian atmosphere consists of approximately 96 % carbon dioxide , 1.9 % argon , 1.9 % nitrogen , and traces of free oxygen , carbon monoxide , water and methane , among other gases , for a mean molar mass of 43.34 g/mol . There has been renewed interest in its composition since the detection of traces of methane in 2003 that may indicate life but may also be produced by a geochemical process , volcanic or hydrothermal activity .   The atmosphere is quite dusty , giving the Martian sky a light brown or orange-red color when seen from the surface ; data from the Mars Exploration Rovers indicate suspended particles of roughly 1.5 micrometres in diameter .   On 16 December 2014 , NASA reported detecting an unusual increase , then decrease , in the amounts of methane in the atmosphere of the planet Mars . Organic chemicals have been detected in powder drilled from a rock by the Curiosity rover . Based on deuterium to hydrogen ratio studies , much of the water at Gale Crater on Mars was found to have been lost during ancient times , before the lakebed in the crater was formed ; afterwards , large amounts of water continued to be lost .   On 18 March 2015 , NASA reported the detection of an aurora that is not fully understood and an unexplained dust cloud in the atmosphere of Mars .   On 4 April 2015 , NASA reported studies , based on measurements by the Sample Analysis at Mars ( SAM ) instrument on the Curiosity rover , of the Martian atmosphere using xenon and argon isotopes . Results provided support for a `` vigorous '' loss of atmosphere early in the history of Mars and were consistent with an atmospheric signature found in bits of atmosphere captured in some Martian meteorites found on Earth . This was further supported by results from the MAVEN orbiter circling Mars , that the solar wind is responsible for stripping away the atmosphere of Mars over the years .

Carbon dioxide <=SEP=> Carbon dioxide ( chemical formula ) is a colorless gas with a density about 60 % higher than that of air ( 1.225 g/L ) that is odorless at normally encountered concentrations . Carbon dioxide consists of a carbon atom covalently double bonded to two oxygen atoms . It occurs naturally in Earth 's atmosphere as a trace gas at a concentration of about 0.04 percent ( 400 ppm ) by volume . Natural sources include volcanoes , hot springs and geysers , and it is freed from carbonate rocks by dissolution in water and acids . Because carbon dioxide is soluble in water , it occurs naturally in groundwater , rivers and lakes , ice caps , glaciers and seawater . It is present in deposits of petroleum and natural gas .   As the source of available carbon in the carbon cycle , atmospheric carbon dioxide is the primary carbon source for life on Earth and its concentration in Earth 's pre-industrial atmosphere since late in the Precambrian has been regulated by photosynthetic organisms and geological phenomena . Plants , algae and cyanobacteria use light energy to photosynthesize carbohydrate from carbon dioxide and water , with oxygen produced as a waste product .   Carbon dioxide is produced by all aerobic organisms when they metabolize carbohydrates and lipids to produce energy by respiration . It is returned to water via the gills of fish and to the air via the lungs of air-breathing land animals , including humans . Carbon dioxide is produced during the processes of decay of organic materials and the fermentation of sugars in bread , beer and winemaking . It is produced by combustion of wood and other organic materials and fossil fuels such as coal , peat , petroleum and natural gas .   It is a versatile industrial material , used , for example , as an inert gas in welding and fire extinguishers , as a pressurizing gas in air guns and oil recovery , as a chemical feedstock and in liquid form as a solvent in decaffeination of coffee and supercritical drying . It is added to drinking water and carbonated beverages including beer and sparkling wine to add effervescence . The frozen solid form of , known as `` dry ice '' is used as a refrigerant and as an abrasive in dry-ice blasting .   Carbon dioxide is the most significant long-lived greenhouse gas in Earth 's atmosphere . Since the Industrial Revolution anthropogenic emissions - primarily from use of fossil fuels and deforestation - have rapidly increased its concentration in the atmosphere , leading to global warming . Carbon dioxide also causes ocean acidification because it dissolves in water to form carbonic acid .

Carbon dioxide in Earth's atmosphere <=SEP=> Carbon dioxide is an important trace gas in Earth 's atmosphere . Currently it constitutes about 0.041 % ( equal to 410 parts per million ; ppm ) by volume of the atmosphere . Despite its relatively small concentration is a potent greenhouse gas and plays a vital role in regulating Earth 's surface temperature through radiative forcing and the greenhouse effect . Reconstructions show that concentrations of in the atmosphere have varied , ranging from as high as 7,000 ppm during the Cambrian period about 500 million years ago to as low as 180 ppm during the Quaternary glaciation of the last two million years .   Carbon dioxide is an integral part of the carbon cycle , a biogeochemical cycle in which carbon is exchanged between the Earth 's oceans , soil , rocks and the biosphere . Plants and other photoautotrophs use solar energy to produce carbohydrate from atmospheric carbon dioxide and water by photosynthesis . Almost all other organisms depend on carbohydrate derived from photosynthesis as their primary source of energy and carbon compounds .   The current episode of global warming is attributed to increasing emissions of and other greenhouse gases into Earth 's atmosphere . The global annual mean concentration of in the atmosphere has increased by more than 40 % since the start of the Industrial Revolution , from 280 ppm , the level it had for the last 10,000 years leading up to the mid-18th century , to 399 ppm as of 2015 . The present concentration is the highest in at least the past 800,000 years and likely the highest in the past 20 million years . The increase has been caused by anthropogenic sources , particularly the burning of fossil fuels and deforestation . The daily average concentration of atmospheric CO2 at Mauna Loa Observatory first exceeded 400 ppm on 10 May 2013 . It is currently rising at a rate of approximately 2 ppm/year and accelerating . An estimated 30 -- 40 % of the released by humans into the atmosphere dissolves into oceans , rivers and lakes , which contributes to ocean acidification .