Organics in environmental ices: sources, chemistry, and impacts
نویسندگان
چکیده
The physical, chemical, and biological processes involving organics in ice in the environment impact a number of atmospheric and biogeochemical cycles. Organic material in snow or ice may be biological in origin, deposited from aerosols or atmospheric gases, or formed chemically in situ. In this manuscript, we review the current state of knowledge regarding the sources, properties, and chemistry of organic materials in environmental ices. Several outstanding questions remain to be resolved and fundamental data gathered before an accurate model of transformations and transport of organic species in the cryosphere will be possible. For example, more information is needed regarding the quantitative impacts of chemical and biological processes, ice morphology, and snow formation on the fate of organic material in cold regions. Interdisciplinary work at the interfaces of chemistry, physics and biology is needed in order to fully characterize the nature and evolution of organics in the cryosphere and predict the effects of climate change on the Earth’s carbon cycle.
منابع مشابه
Formation rates of complex organics in UV irradiated CH3OH-rich ices I: Experiments
Context. Gas-phase complex organic molecules are commonly detected in the warm inner regions of protostellar envelopes, so-called hot cores. Recent models show that photochemistry in ices followed by desorption may explain the observed abundances. There is, however, a general lack of quantitative data on UV-induced complex chemistry in ices. Aims. This study aims to experimentally quantify the ...
متن کاملDescent without Modification? The Thermal Chemistry of H2O2 on Europa and Other Icy Worlds.
The strong oxidant H2O2 is known to exist in solid form on Europa and is suspected to exist on several other Solar System worlds at temperatures below 200 K. However, little is known of the thermal chemistry that H2O2 might induce under these conditions. Here, we report new laboratory results on the reactivity of solid H2O2 with eight different compounds in H2O-rich ices. Using infrared spectro...
متن کاملUV photolysis, organic molecules in young disks, and the origin of meteoritic amino acids
The origin of complex organic molecules such as amino acids and their precursors found in meteorites and comets is unknown. Previous studies have accounted for the complex organic inventory of the Solar System by aqueous chemistry on warm meteoritic parent bodies, or by accretion of organics formed in the interstellar medium. This paper proposes a third possibility: that complex organics were c...
متن کاملExploring the origins of carbon in terrestrial worlds.
Given the central role of carbon in the chemistry of life, it is a fundamental question as to how carbon is supplied to the Earth, in what form and when. We provide an accounting of carbon found in solar system bodies, and in particular a comparison between the organic content of meteorites and that in identified organics in the dense interstellar medium (ISM). Based on this accounting, identif...
متن کاملProduction and Chemical Analysis of Cometary Ice Tholins
dances of nitriles and other nitrogen-containing organics. The most thermodynamically favored cometary ices are Organic heteropolymers that we call here ice tholin II have been produced by plasma discharge irradiation of water/ clathrate hydrates (Delsemme and Swings 1952, Delsemme methanol/carbon dioxide/ethane cocondensed ices in a rough 1976); unprocessed hydrocarbons are expected primarily ...
متن کامل