Glacial/interglacial variations in atmospheric carbon dioxide

  title={Glacial/interglacial variations in atmospheric carbon dioxide},
  author={Daniel M. Sigman and Edward A. Boyle},
Twenty years ago, measurements on ice cores showed that the concentration of carbon dioxide in the atmosphere was lower during ice ages than it is today. As yet, there is no broadly accepted explanation for this difference. Current investigations focus on the ocean's ‘biological pump’, the sequestration of carbon in the ocean interior by the rain of organic carbon out of the surface ocean, and its effect on the burial of calcium carbonate in marine sediments. Some researchers surmise that the… 

Impact of brine-induced stratification on the glacial carbon cycle

Abstract. During the cold period of the Last Glacial Maximum (LGM, about 21 000 years ago) atmospheric CO2 was around 190 ppm, much lower than the pre-industrial concentration of 280 ppm. The causes

Air-sea disequilibrium enhances ocean carbon storage during glacial periods

It is found that air-sea disequilibrium greatly amplifies the effects of cooler temperatures and iron fertilization on glacial ocean carbon storage even as the efficiency of the soft-tissue biological pump decreases.

Glacial expansion of oxygen-depleted seawater in the eastern tropical Pacific

Two tandem proxy reconstructions provide evidence of a downward expansion of oxygen depletion in the eastern Pacific during the last glacial, with no indication of greater oxygenation in the upper reaches of the water column, contributing to the lower levels of atmospheric carbon dioxide during this period.

A deeper respired carbon pool in the glacial equatorial Pacific Ocean

Ocean biology could control atmospheric δ13C during glacial‐interglacial cycle

Estimates of changes in the global carbon budget are often based on the assumption that the terrestrial biosphere controls the isotopic composition of atmospheric CO2 since terrestrial plants

Extensive phytoplankton blooms in the Atlantic sector of the glacial Southern Ocean

[1] The sources and sinks of atmospheric carbon dioxide over glacial/interglacial cycles are under debate. Variation in productivity of the Antarctic Circumpolar Current (ACC) could potentially play

The role of shelf nutrients on glacial‐interglacial CO2: A negative feedback

In the past 800 thousand years and before industrialization, the largest variations in atmospheric CO2 concentration (pCO2) occurred in connection with the glacial cycles that characterized Earth's

Paleoceanographic reconstruction of nitrate consumption in the Atlantic Ocean using foraminifera-bound nitrogen isotopes

Within the last few decades, evidences emerged that the marine biological production is one of the factors controlling Earth’s climate. Changes in the efficiency of the marine biological pump are

Glacial-interglacial atmospheric CO2 change —The glacial burial hypothesis

  • N. Zeng
  • Environmental Science, Geography
  • 2003
Organic carbon buried under the great ice sheets of the Northern Hemisphere is suggested to be the missing link in the atmospheric CO2 change over the glacial-interglacial cycles. At glaciation, the

Marine carbon cycle evolution in the eastern equatorial pacific over the last deglaciation

Although the glacial-interglacial climate cycles of the late Pleistocene were very likely paced by changes in solar insolation, the full amplitude of these climate cycles was only achieved with the



Evidence for lower productivity in the Antarctic Ocean during the last glaciation

BOTH increased biological productivity and more efficient uptake of upwelled nutrients in high-latitude oceans have been proposed1–5 as mechanisms responsible for the glacial reduction in atmospheric

Large changes in oceanic nutrient inventories from glacial to interglacial periods

CHANGES in ocean chemistry and circulation have been invoked to explain the lower atmospheric CO2 concentrations of glacial periods observed in ice-core records1. The processes that modulate these

Carbon isotope composition of atmospheric CO2 during the last ice age from an Antarctic ice core

BUBBLES of ancient air in polar ice cores have revealed that the atmospheric concentration of CO2 during the Last Glacial Maximum was 180–200 p.p.m.v., substantially lower than the pre-industrial

Evolution of the nitrogen cycle and its influence on the biological sequestration of CO2 in the ocean

Over geological time, photosynthetic carbon fixation in the oceans has exceeded respiratory oxidation of organic carbon. The imbalance between the two processes has resulted in the simultaneous

Increases in terrestrial carbon storage from the Last Glacial Maximum to the present

EVIDENCE from ice cores1 indicates that concentrations of atmospheric carbon dioxide were lower by about 75 p.p.m. during the Last Glacial Maximum (LGM; ∼18,000 years ago) than during the present

Ocean chemistry during glacial time

Oceanic Cd/P ratio and nutrient utilization in the glacial Southern Ocean

It is shown that present-day cadmium and phosphorus concentrations in the global oceans can be explained by a chemical fractionation during particle formation, whereby uptake of Cadmium occurs in preference to uptake of phosphorus.

Effect of deep-sea sedimentary calcite preservation on atmospheric CO2 concentration

DURING the last glaciation, the atmospheric carbon dioxide concentration was about 30% less than the Holocene pre-industrial value1. Although this change is thought to originate in oceanic

glacial-interglacial Co2 change : the iron hypothesis

Several explanations for the 200 to 280 ppm glacial/interglacial change in atmospheric CO2 concentrations deal with variations in southern ocean phytoplankton productivity and the related use or

Dual modes of the carbon cycle since the Last Glacial Maximum

The global carbon cycle is shown to have operated in two distinct primary modes on the timescale of thousands of years, one when climate was changing relatively slowly and another when warming was rapid, each with a characteristic average stable-carbon-isotope composition of the net CO2 exchanged by the atmosphere with the land and oceans.