«After examining rocks 450 million years old or older, we believe the drop was caused by a massive burial
of organic carbon during the time period,» Quinton said.
Not exact matches
The team's findings provide one possible mechanism for an observed increase in the concentration
of dissolved
organic carbon in the surface waters
of North America and Europe
during the last few decades, and have implications for management
of water quality in coastal zones worldwide.
During Curiosity's first «meals»
of Martian soil, baked inside the robot's ovens,
carbon and hydrogen were found to have reacted with chlorine, creating
organic molecules.
Billions
of planktonic organisms, too tiny to be seen with the naked eye, make this valuable service possible: When
carbon dioxide from the atmosphere dissolves in seawater, various species convert it to
organic carbon and other
organic components
during photosynthesis.
Other possibilities are the decomposition
of organic matter in terrestrial settings, or the release
of methane and
carbon dioxide from deeply buried rocks
during volcanic events.
David, I havent been keeping up with all the PETM research, but I do recall that individual plankton recovered from Bass River, New Jersey show a single step CIE. Due to the high sedimentation rate
of coastal fluvial systems, Bass River sediments are consistent with a much shorter duration
of organic carbon release
during the PETM (estimated as less than 500 years).
We introduce a
carbon cycle model that would explain the PETM by global warming following a bolide impact, leading to the oxidation
of terrestrial
organic carbon stores built up
during the late Paleocene.
Soot - Particles formed
during the quenching
of gases at the outer edge
of flames
of organic vapors, consisting predominantly
of carbon, with lesser amounts
of oxygen and hydrogen present as carboxyl and phenolic groups and exhibiting an imperfect graphitic structure.
Knies, J. & Stein, R. New aspects
of organic carbon deposition and paleoceanographic implications along the northern Barents Sea margin
during the last 30,000 years.
The
carbon loss occurred first through the removal
of the original vegetation, which stored much
carbon in its leaves, stems and trunks; then through the oxidation
of carbon in newly exposed soils; and finally through increased soil erosion, which carried away much
of the
organic - rich sediment
during flooding.
While 50 %
of the sequestered
carbon formed
during photosynthesis is respired before sinking into the dark depths, a tremendous pool
of dissolved
organic carbon has been created that may not be respired for decades, centuries or millennia and slowly contributes to the pool
of DIC at various depths and locations (Giorgiou 2002).
«'' A second, rarely touched upon question is associated with the apparently limited amount
of organic carbon that had been released from permafrost terrain in previous periods
of climatic warming such as e.g. the Medieval Warm Period or
during the Holocene Climatic Optimum.
In fact, if we continue on our current path
of high heat - trapping emissions, the region is projected to see forest fires
during June and July at two to three times its current rate.2, 6 Some 1 billion metric tons
of organic matter and older - growth trees could burn7, 15 — accelerating the release
of stored
carbon and creating a dangerous global warming amplification or feedback loop.5, 14
They key, scientists explain, lies in ensuring that a sufficiently high enough percentage
of organic carbon produced
during the blooms reaches middle - depth waters, at which point it would remain in deeper underwater currents for decades.
«Modelling studies are also in moderately good agreement with observations
during the first half
of the 20th century when both anthropogenic and natural forcings are considered, although assessments
of which forcings are important differ, with some studies finding that solar forcing is more important (Meehl et al., 2004) while other studies find that volcanic forcing (Broccoli et al., 2003) or internal variability (Delworth and Knutson, 2000) could be more important... The mid-century cooling that the model simulates in some regions is also observed, and is caused in the model by regional negative surface forcing from
organic and black
carbon associated with biomass burning.
The rapidity with which
organic carbon can build up in soils is also indicated by examples
of buried steppe soils formed
during short - lived interstadial phases in Russia and Ukraine.
However, coatings
of organic carbon aerosol on hygroscopic aerosol such as sulphate may lead to suppression
of the rate
of water uptake
during cloud activation (Xiong et al., 1998; Chuang, 2003).