Sentences with phrase «on ice core analysis»

Not exact matches

The analysis focuses on two ice cores drilled in 2013 from Mount Hunter in Alaska's Denali National Park, and an older ice core from Canada's Mount Logan.

An analysis of CO2 preserved in ice cores shows that for more than 600,000 years the ocean had a pH of approximately 8.2 (pH is the acidity of a solution measured on a 14 - point scale, with a pH below 7 being acidic and above 7, basic).

The team based its analysis on ratios of oxygen and hydrogen isotopes in ice cores drilled in East Antarctica.

Understanding how that would affect the climate will require going beyond historical records of climate change, or even the information encoded in tree rings or ice cores, to what scientists call «deep time» records of conditions on Earth, according to a new NAS analysis.

This analysis of ice cores relies on the assumption that there is limited biological activity altering the environment in the snow during its transition into ice.

Ice - core analysis on the Siple Coast of West Antarctica.

Time will tell of course — confirming studies from ice cores and independent analyses are already published, with more rumoured to be on their way.

Data on greenhouse gas abundances going back beyond a million years, that is, beyond the reach of antarctic ice cores, are still rather uncertain, but analysis of geological samples suggests that the warm ice - free periods coincide with high atmospheric CO2 levels.

Note: emissions are estimated independently of the model, based on chemical analysis of ice core samples from Greenland, industrial production, etc..

Paleoclimatology estimates are based on analyses of ice cores and other paleo indicators that are used to estimate temperature changes and forcing changes.

This «new evidence» is based on a single analysis of «proxy» data (that is, data that do not come from thermometers but rather from sources like tree rings, ice cores, corals, and ocean and lake sediments) showing the twentieth century to be the warmest in the past thousand years.

Recent analysis of the Greenland ice cores, by Chylek et al., has proven that the powerful AMO variability has been part and parcel of the Greenland climate for thousands of years, pushing temperatures higher and lower depending on the cycle point.

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).

However, both the driving force and the climate reconstructions over the pre-industrial era are based on the analysis of the natural archives of climate sensitive quantities, such as the growth of trees and seashells, and the changes of chemical, biological, and isotopic compositions in lake sediments and ice core samples.

My immediately following (and more detailed) analyses of Wegman et al's sections on tree rings, as well as ice cores and coral proxies (also largely copied from Bradley's text book) eventually came to Bradley's attention, apparently via Richard Littlemore at Desmogblog.

The problem with your analysis is that the ice cores already reflect the ocean temperature by measuring the ratio of Deuterium to Hydrogen based on the difference in the relative evaporation of each, vs. temperature.

In such case for proper scientific analysis it is better to rely on good quality data where available and proxy data for historical reconstructions — like for instance satellite data & ice core data.

Wenk Physics Institute, University of Bern, CH — 3012 Bern, Sidlerstrasse 5, Switzerland Studies on air trapped in old polar ice1, 2 have shown that during the last ice age, the atmospheric carbon dioxide concentration was probably significantly lower than during the Holocene — about 200 p.p.m. rather than 270 p.p.m.. Also, Stauffer et al. 3 recently showed by detailed analyses of Greenland ice cores, that during the ice age, between about 30,000 and 40,000 yr BP, the atmospheric CO2 level probably varied between 200 and 260 p.p.m..

Hansen's climate analyses have been based not only on the very basic physics that goes into climate model design, but on the detailed studies of the geological ice core and isotope records that are used to constrain and confirm climate model sensitivity.

Two comprehensive chapters on dating methods provide the foundation for all paleoclimatic studies and are followed by up - to - date coverage of ice core research, continental geological and biological records, pollen analysis, radiocarbon dating, tree rings and historical records.

With regard to proxy studies, same basic questions, are these direct or passive correlations, what evidence that tree ring core thickness depends only on temperature (what about precipitation, cloud cover, volcanic activity, sea surface temperatue changes, sea current changes, solar irradiance changes, cloud cover, etc.) How are these variables accounted for when analysis of ice cores is completed, or for that matter when computer models, and / or proxy studies are completed.

The point of this remark is that no one up to present date has conducted any analysis of this sort on the ice core data, therefore my assertion that currently «you have no data of adequate quality from past proxies, so the argument of «unprecedented» growth can not be used» is perfectly valid and is true.