What is the approximate range of CO2 concentrations in the ice core record?
What is the approximate range of CO2 concentrations in the ice core record?
between 170 and 300 parts per million
Over the last 800,000 years atmospheric CO2 levels as indicated by the ice-core data have fluctuated between 170 and 300 parts per million by volume (ppmv), corresponding with conditions of glacial and interglacial periods.
What source do we get the 800000 year old record of CO2 from?
Scientists can study Earth’s climate as far back as 800,000 years by drilling core samples from deep underneath the ice sheets of Greenland and Antarctica. Detailed information on air temperature and CO2 levels is trapped in these specimens.
How far back does the CO2 record go in Antarctica?
In 2008, Dieter Lüthi and other scientists pubished a paper in Nature that extended the ice core record of atmospheric CO2 concentrations from 650,000 years before present to 800,000 years before present. To do this, they analyzed the lowest 200 metres of the ice core drilled at EPICA Dome C in Antarctica.
What information does the Vostok ice core record reveal?
Ice core samples taken at the Vostok station are used to collect data on historical carbon dioxide levels. The data consist of measurements of the percentage of atmospheric gasses, such as CO2 in fossil air bubbles that have been trapped in snow flakes and compressed into ice over 400,000 years old.
What is the average CO2 ppm during the interglacials for the last 400000 years?
They tell us that levels of carbon dioxide (CO2) in the atmosphere are higher than they have been at any time in the past 400,000 years. During ice ages, CO2 levels were around 200 parts per million (ppm), and during the warmer interglacial periods, they hovered around 280 ppm (see fluctuations in the graph).
What was the CO2 concentration 20000 years ago?
During all of the cycles between ice ages and warm periods over the past million years, atmospheric carbon dioxide never climbed higher than 300 parts per million. At the end of the last ice age around 20,000 years ago, it was 280 ppm.
How far does the oldest core go back in time?
The oldest continuous ice core records extend to 130,000 years in Greenland, and 800,000 years in Antarctica.
How reliable are ice cores?
Ice cores are remarkably faithful recorders of past climate, providing multiply duplicated reconstructions with small and quantifiable uncertainties.
How does carbon dioxide co2 influence the Earth’s temperature?
Carbon dioxide is a greenhouse gas: a gas that absorbs and radiates heat. But increases in greenhouse gases have tipped the Earth’s energy budget out of balance, trapping additional heat and raising Earth’s average temperature. Carbon dioxide is the most important of Earth’s long-lived greenhouse gases.
Which ice core was used to determine CO2 concentrations from around 5000 years ago until 420000 years ago?
Climate and the Atmospheric History of the Past 420,000 years from the Vostok Ice Core, Antarctica. Nature 1999; 399: 429-436.
Does the GISP2 ice core cover the modern period?
The GISP2 ice core only extends up to 1855 – 95 years before 1950. This means that none of the modern observational temperature period overlaps with the proxy reconstruction. (Easterbrook’s graph shows the uptick in the final 100 years or so of the record – shown in red – incorrectly indicating that it is the observational temperature period.)
What does GISP2 stand for?
O n 1 July 1993, after five years of drilling, the Greenland Ice Sheet Project Two (GISP2,) penetrated through the ice sheet and 1.55 meters into bedrock recovering an ice core 3053.44 meters in depth, the deepest ice core thus far recovered in the world.
What is a GISP2 temperature reconstruction?
A temperature reconstruction using the Greenland Ice Sheet Project 2 (“ GISP2 ”) ice core was first published by Prof Kurt Cuffey and Dr Gary Clow in a 1997 paper published in the Journal of Geophysical Research: Oceans. Prof Richard Alley of Penn State University also used the record in a 2000 paper.
Is a multi-core Holocene reconstruction better than GISP2?
Speaking to Carbon Brief, Vinther suggests that this multi-core Holocene reconstruction provides a number of advantages over the old GISP2 series, using ice core 18O data corrected for past elevation change and “ tuned ” to fit ice core borehole temperatures at four locations.