Sentences with phrase «by isotopic composition»

Instead of CO2 concentrations being about 15 p.p.m.v. lower, the CO2 / temperature shift can also be explained by isotopic composition overestimating temperature by about 1 °C.

Not exact matches

This is a particularly useful region because the oxygen isotopic composition of the seawater is largely determined by the flow of water through the Strait of Gibraltar, which in turn is sensitive to changes in global sea level — in a way like the pinching of a hosepipe.

By contrast, in transpiration, plants simply suck water out of the soil and push it into the air without changing its isotopic composition.

By comparing the results to the isotopic composition of the trapped gas, the researchers revealed how dense the Martian atmosphere was at the time when the gas became trapped in the meteorite.

Co-author, Christophe Lécuyer explained: «According to this method, it is possible to calculate the temperature of the water in which these fish lived by applying an equation linking the isotopic composition of the fossilised remains to the temperature of mineralisation of their skeleton.

It is possible to reconstruct past precipitation changes by measuring the stable hydrogen isotopic composition in terrestrial plant waxes because rainfall is the primary source of hydrogen stored in plant material.

Keep in mind that the classic paper by Hayes et al (1976) showed that isotopic composition of forams in marine cores fluctuated on orbital time - scales in accordance with Milankovitch.

As discussed by Veizer et al. there is a major discrepancy during the mid-Mesozoic (120 to 220 Ma) between cold low - latitude temperatures deduced from the oxygen isotopic composition (λ 18O) of fossils and high levels of CO2 and net radiative forcing.

[5] Linsley et al. (2006) reconstructed sea - surface temperature and sea surface salinity in the southwest Pacific starting circa 1600CE by measuring the oxygen isotopic composition of four Porites coral records from Rarotonga and two from Fiji.

The Medieval Warm Period in AD 980-1250 is the most distinctive climate period in the whole sediment sequence identified by changes in sediment colour, X-ray density, varve thickness, LOI, as well as the isotopic composition of hydrogen in kerogen.

... 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 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.

Ehlers reported at last December's American Geophysical Union meeting that in a climate model, the rise of the Andes themselves alters climate — for example, by changing the source and therefore the isotopic composition of precipitation.

I thought one could get other evidence on these matters by looking at the isotopic composition of the CO2 and also by looking at the correlation between CO2 changes and change in O2.