Sentences with phrase «carbon isotopic composition»

The hydrogen and carbon isotopic composition of methane from natural gases of various origins

Next, the methane in this air is combusted to produce carbon dioxide, which is analysed for its carbon isotopic composition — or carbon - 13 to carbon - 12 ratio.

To carry out the study, the researchers developed a new sample extraction and mass spectrometry method that allowed them to precisely measure the carbon isotopic composition of methane in very small ice core samples.

Finally, the carbon isotopic composition of Ar.

Not exact matches

Because the isotopic ratios of carbon and hydrogen display geographic variation, the composition of a feather can reveal where the bird was when the feather grew.

«During photosynthesis plants bind atmospheric carbon, whose isotopic composition is preserved in resins over millions of years, and from this, we can infer atmospheric oxygen concentrations,» explains Ralf Tappert.

The information about oxygen concentration comes from the isotopic composition of carbon or rather from the ratio between the stable carbon isotopes 12C and 13C.

«They tell us the story of the chemical and isotopic compositions of the atmospheric carbon dioxide.»

Here, we report surface water dissolved inorganic carbon (DIC) and sedimentary organic carbon concentrations and their isotopic compositions in the rapidly urbanized Jiaozhou Bay in northeast China as well as carbonate parameters in effluents of three large WWTPs around the bay.

Then the magnitude of the carbon spike depends on its isotopic composition.

Funny how difficult it is for him and his fellow denialati to look at 1) where that carbon came from 2) its isotopic composition 3) the fact that it takes a while for permafrost to melt and oceans to become a source rather than a sink 4) the fact that humans are producing about 2x as much carbon as is going into the atmosphere 5) the remaining CO2 is acidifying the oceans

«Measurement of atmospheric mixing ratios, decline of O2 mixing ratios, pCO2 in the ocean, and the isotopic carbon composition and other stuff tells us about the source of CO2 increases.

Because of these confounding factors, palaeoreconstructions based on the isotopic composition of organic carbon (δ13C) will almost certainly have to be based on the isotopic signatures of organic compounds that can be associated with a single species, or group of physiologically similar species

(Partisan) description: The authors studied the isotopic composition of carbon (δ13C) and hydrogen (δD) in organic matter found in two sediment cores retrieved from Lake Korttajarvi.

It's possible to back out what the isotopic composition of the carbon source was leading to the atmospheric increase through the deglaciation.

... Onset of a major reorganization of the carbon cycle immediately precedes the initiation of extinction and is punctuated by a sharp (3 ‰), short - lived negative spike in the isotopic composition of carbonate carbon.

The stable isotopic composition of the carbon in carbon dioxide over the last 24,000 years illuminates past carbon cycle behavior.

The methane produced by the burning of biomass, like wood, contains more of the heavier isotope (carbon - 13) relative to the lighter isotope (carbon - 12), than methane which is produced in wetlands,» explains Professor Thomas Blunier, Centre for Ice and Climate at the Niels Bohr Institute at the University of Copenhagen.The researchers have measured the isotopic composition of the methane in ice cores that are drilled up from the Greenland ice cap at the NEEM project in northwestern Greenland.

With regard to the former, I seem to recall reading somewhere that the isotopic composition of the carbon in fossil fuels (and limestone used to make cement) differs from the average composition in current sinks and that can be used to look at where the CO2 is coming from.