Sentences with phrase «in ice core measurements»

This is hardly measureable, and is not detectable within the margins of error in ice core measurements for the last interglacial - glacial - interglacial transitions.

The CO2 in short gets depleted in ice core measurements and has not been corrected properly.

Until recently, analytical issues in the ice core measurements provided a limitation on assessing the deglacial isotopic evolution of 13C.

Not exact matches

In addition to the isotope concentration, the air bubbles trapped in the ice cores allow for measurement of the atmospheric concentrations of trace gases, including greenhouse gases carbon dioxide, methane, and nitrous oxidIn addition to the isotope concentration, the air bubbles trapped in the ice cores allow for measurement of the atmospheric concentrations of trace gases, including greenhouse gases carbon dioxide, methane, and nitrous oxidin the ice cores allow for measurement of the atmospheric concentrations of trace gases, including greenhouse gases carbon dioxide, methane, and nitrous oxide.

The cores were also sampled for chemical measurements in Dartmouth's Ice Core Laboratory to determine the age of each ice layIce Core Laboratory to determine the age of each ice layice layer.

All measurements of lead and other chemicals used in this study were made using DRI's continuous ice core analytical system.

Measurements of salt particles in ice cores suggest that storminess rose toward the end of the occupation, perhaps making voyages to hunt and trade walrus ivory even more dangerous.

We know from these measurements from the ice cores with Icille and her companions, from various ages of ice, that before 1850 the CO2 in the atmosphere was very steady for about 10,000 years going back in time.

«The anomaly was detected in much more limited measurements of the Byrd ice core in the 1990s,» notes McConnell, «but exactly what it was or what created it wasn't clear.

«Detailed chemical measurements in Antarctic ice cores show that massive, halogen - rich eruptions from the West Antarctic Mt. Takahe volcano coincided exactly with the onset of the most rapid, widespread climate change in the Southern Hemisphere during the end of the last ice age and the start of increasing global greenhouse gas concentrations,» according to McConnell, who leads DRI's ultra-trace chemical ice core analytical laboratory.

The past climates that forced these changes in ice volume and sea level were reconstructed mainly from temperature - sensitive measurements in ocean cores from around the globe, and from ice cores.

o Ice core and sea - bed sediment measurements show no evidence that changes in CO2 drive world temperatures or climate.

Continuous methane measurements from a late Holocene Greenland ice core: Atmospheric and in - situ signals.

Measurements of Bacterial Concentrations on a Millimeter Scale in Ice Cores With a Scanning Laser Fluorescence Spectrometer.

Changes in atmospheric carbonyl sulfide over the last 54,000 years inferred from measurements in Antarctic ice cores, Journal of Geophysical Research: Atmospheres, 121, p. 1943 - 1954.

Post-coring entrapment of modern air in some shallow ice cores collected near the firn - ice transition: evidence from CFC - 12 measurements in Antarctic firn air and ice cores.

Fluorescense Measurements of Microbial Life in the WAIS Divide Ice Core.

Although it has proved quite challenging to do the analyses, there are a limited number of measurements of the 13C / 12C ratio in ice cores.

Although it has proved quite challenging to do the analyses, there are a limited number of measurements of the 13C / 12C ratio in ice cores.

[Response CO2 levels are currently higher than for any time when we have direct measurements (directly, from 1950; before that, from air trapped in ice cores), which amounts to the last 780,000 years (see, e.g., a picture here for the last 400 kyr).

These measurements, supplemented by analyses of air bubbles trapped in ice core samples, show unequivocally that atmospheric CO2 has increased from a pre-industrial level of 277 ppm in 1750 to present day concentrations that are approaching 390 ppm.

in connecting ice core CO2 measurments with the Keeling measurements.

In addition to the data from tree rings, there are also of measurements of the 13C / 12C ratio in the CO2 trapped in ice coreIn addition to the data from tree rings, there are also of measurements of the 13C / 12C ratio in the CO2 trapped in ice corein the CO2 trapped in ice corein ice cores.

Re # 33 (Dave D.): Ice core measurement issues aside, remember that there has to be some degree of lag because a) the initial warming is from Milankovitch changes, not CO2, and 2) the delayed turnover of ocean water means that not all the CO2 will outgas in a short period of time.

Figures A and B show past variations in the global mean temperature inferred from direct measurements (A) and from the analysis of ice - cores (B).

«In addition, we are currently developing a method that also allows for high - precision hydrogen isotopic measurements on methane in ice cores, which will further improve our emission flux constraints,» revealed FischeIn addition, we are currently developing a method that also allows for high - precision hydrogen isotopic measurements on methane in ice cores, which will further improve our emission flux constraints,» revealed Fischein ice cores, which will further improve our emission flux constraints,» revealed Fischer.

please read Z. Jaworowski's (with Segalstad and Ono) many papers on this subject of trapped gases in glaciers, where he discusses the over 20 mechanical and chemical processes that make accurate measurements impossible; even in shallow cores above the point where co2 is supposedly permanently trap in ice cavities in the firn, co2 concentrations are already 20 - 40 % lower than those measured in air at mauna loa.

In your case, the ice cores must be wrong, in my case, there is no problem with ice core CO2 (neither with historical CO2 levels over the oceans), as the 0.3 K temperature increase in the period 1900 - 1950 causes an increase of about 0.9 ppmv CO2, which is within the accuracy of the ice core measurements, the rest of the observed increase is due to human emissionIn your case, the ice cores must be wrong, in my case, there is no problem with ice core CO2 (neither with historical CO2 levels over the oceans), as the 0.3 K temperature increase in the period 1900 - 1950 causes an increase of about 0.9 ppmv CO2, which is within the accuracy of the ice core measurements, the rest of the observed increase is due to human emissionin my case, there is no problem with ice core CO2 (neither with historical CO2 levels over the oceans), as the 0.3 K temperature increase in the period 1900 - 1950 causes an increase of about 0.9 ppmv CO2, which is within the accuracy of the ice core measurements, the rest of the observed increase is due to human emissionin the period 1900 - 1950 causes an increase of about 0.9 ppmv CO2, which is within the accuracy of the ice core measurements, the rest of the observed increase is due to human emissions.

Ice - core CO2 measurements are direct measurements on air that has been enclosed in bubbles.

Scientists can also use the ice cores to correlate the concentration of carbon dioxide in the atmosphere with climate change — a measurement that has emphasized the role of carbon dioxide in global warming.

Carbon dioxide measurements on Dome C ice, focusing on the interval 390 to 650 kyr before present, bp (2,700 — 3,060 m) 4, confirmed the strong coupling between CO2 and Antarctic temperature found1 in the Vostok ice core for the past 420 kyr.

«Measurements of oxygen isotopes from the GISP2 ice core suggest the ending of the Younger Dryas took place over just 40 — 50 years in three discrete steps, each lasting five years.

Mike Flynn November 19, 2015 at 9:33 pm «Measurements of oxygen isotopes from the GISP2 ice core suggest the ending of the Younger Dryas took place over just 40 — 50 years in three discrete steps, each lasting five years.

We will interpret recently completed measurements of 35 chemical - proxies in the ice - core and relate these to similar studies in other Arctic ice cores, such as by using real - world contaminant transport to validate atmospheric circulation models and chemical - signature sourcing.

Can anyone point me to literature about how we know that everything in the ice core keeps the same relative depth, or if it is known not to, how measurements are adjusted to acount for differential drift?

And this is a crucial point; Salby's conclusions are based on the best measurements; his critics are rabbiting on about ice core data and other proxies which are up there with how's your mother in terms of evidence.

Indeed, the interannual and day - to - day variability of the SIO measurements would explain why we get such large fluctuations in the ice - core data (before they are edited).

Playing the «devil's advocate,» Tim Ball has an essay in Watts Up With That explaining why he thinks the ice cores give little practical information, or at least are not precise measurements of temperatures and time - lines.

And as said before, the ice cores measurements at one side and the emissions estimates for the period 1900 - 1960 indicates that nature was a net sink over that period, be it that in some years nature might have been a source, in other years a sink.

There is extensive experimental data in the physics and chemistry of the greenhouse process, in tens of thousands of data sets demonstrating impacts of the changing climate, as well as in paleo - climatic measurements, such as ice cores.

Also, given the atmospheric CO2 measurements at South Pole range between 246.59ppm - 521.48 ppm I don't see how the trapped CO2 in the ice - core bubbles could accurately represent the back - ground level.

Precision of Ice Core Measurements: Some of the best data we have of historic temperatures are the studies of isotopes of gases and various components of the atmosphere in ice cores, such as Vostok in Antarctica, and GRIP in GreenlaIce Core Measurements: Some of the best data we have of historic temperatures are the studies of isotopes of gases and various components of the atmosphere in ice cores, such as Vostok in Antarctica, and GRIP in Greenlaice cores, such as Vostok in Antarctica, and GRIP in Greenland.

The 1942 «peak» is nowhere seen in any other direct measurement (high resolution ice cores from Law Dome) neither in stomata data for the past century, neither in coralline sponges, the latter based on 13C / 12C ratio's which certainly should change if there was an important change in inputs or outputs from vegetation or oceans.

''... worked with two sediment cores they extracted from the seabed of the eastern Norwegian Sea, developing a 1000 - year proxy temperature record «based on measurements of δ18O in Neogloboquadrina pachyderma, a planktonic foraminifer that calcifies at relatively shallow depths within the Atlantic waters of the eastern Norwegian Sea during late summer,» which they compared with the temporal histories of various proxies of concomitant solar activity... This work revealed, as the seven scientists describe it, that «the lowest isotope values (highest temperatures) of the last millennium are seen ~ 1100 - 1300 A.D., during the Medieval Climate Anomaly, and again after ~ 1950 A.D.» In between these two warm intervals, of course, were the colder temperatures of the Little Ice Age, when oscillatory thermal minima occurred at the times of the Dalton, Maunder, Sporer and Wolf solar minima, such that the δ18O proxy record of near - surface water temperature was found to be «robustly and near - synchronously correlated with various proxies of solar variability spanning the last millennium,» with decade - to century - scale temperature variability of 1 to 2 °C magnitude.&raquin Neogloboquadrina pachyderma, a planktonic foraminifer that calcifies at relatively shallow depths within the Atlantic waters of the eastern Norwegian Sea during late summer,» which they compared with the temporal histories of various proxies of concomitant solar activity... This work revealed, as the seven scientists describe it, that «the lowest isotope values (highest temperatures) of the last millennium are seen ~ 1100 - 1300 A.D., during the Medieval Climate Anomaly, and again after ~ 1950 A.D.» In between these two warm intervals, of course, were the colder temperatures of the Little Ice Age, when oscillatory thermal minima occurred at the times of the Dalton, Maunder, Sporer and Wolf solar minima, such that the δ18O proxy record of near - surface water temperature was found to be «robustly and near - synchronously correlated with various proxies of solar variability spanning the last millennium,» with decade - to century - scale temperature variability of 1 to 2 °C magnitude.&raquIn between these two warm intervals, of course, were the colder temperatures of the Little Ice Age, when oscillatory thermal minima occurred at the times of the Dalton, Maunder, Sporer and Wolf solar minima, such that the δ18O proxy record of near - surface water temperature was found to be «robustly and near - synchronously correlated with various proxies of solar variability spanning the last millennium,» with decade - to century - scale temperature variability of 1 to 2 °C magnitude.»

«We are able, for the first time, to accurately reproduce the ice - core record for the last 800,000 years — the record of atmospheric C02 based on measurements of carbon dioxide in gas bubbles in ice,» Tripati said.

Typical reconstructions of historic heliospheric magnetic field (HMF) BHMF are based on the analysis of the sunspot activity, geomagnetic data or on measurement of cosmogenic isotopes stored in terrestrial reservoirs like trees (14C) and ice cores (10Be).

For instance the Vostok ice - core data over 415,000 years has an average measurement - spacing of 756 years, meaning that the likelihood of measuring an increase in atmospheric CO2 as the one measured at Mauna Loa over the last 50 years, if one existed in the Vostok ice - core samples, amounts to 6.6 % (i.e. 50/756).

Prior to direct telescopic measurements of sunspots, which commenced around 1610, knowledge of solar activity is inferred indirectly from the 14C and 10Be cosmogenic isotope record in tree rings and ice cores, respectively, which exhibit solar related cycles near 90, 200 and 2,300 years.

Proxy data such as those generated from ice core samples, measurements of tree rings intervals, bore samples taken from sediments from the ocean and sea floor, and measurement of gases from bubbles trapped in ice are some examples of preserved physical characteristics of the past used by scientists to reconstruct prevailing climatic conditions in the past.

My comment did not relate to the ice cores but to CO2 measurements of the atmosphere in the Vostok region similar to the atmospheric measurements taken at Mauna Loa.