The Sloan Digital Sky Survey III (SDSS-III) presents the first spectroscopic data from the Baryon Oscillation Spectroscopic Survey (BOSS). This ninth data release (DR9) of the SDSS project includes ...535,995 new galaxy spectra (median z ~ 0.52), 102,100 new quasar spectra (median z ~ 2.32), and 90,897 new stellar spectra, along with the data presented in previous data releases. These spectra were obtained with the new BOSS spectrograph and were taken between 2009 December and 2011 July. In addition, the stellar parameters pipeline, which determines radial velocities, surface temperatures, surface gravities, and metallicities of stars, has been updated and refined with improvements in temperature estimates for stars with T eff < 5000 K and in metallicity estimates for stars with Fe/H > -0.5. DR9 includes new stellar parameters for all stars presented in DR8, including stars from SDSS-I and II, as well as those observed as part of the SEGUE-2. The astrometry error introduced in the DR8 imaging catalogs has been corrected in the DR9 data products. The next data release for SDSS-III will be in Summer 2013, which will present the first data from the APOGEE along with another year of data from BOSS, followed by the final SDSS-III data release in 2014 December.
Royer et al use the inverse relationship between leaf stomatal indices and the partial pressure of carbon dioxide in modern Ginkgo biloba and Metasequoia glyptostroboides to develop a carbon dioxide ...reconstruction based on fossil Ginkgo and Metasequoia cuticles for the middle Paleocene to early Eocene and middle Miocene.
Understanding the link between the greenhouse gas carbon dioxide (CO2) and Earth's temperature underpins much of paleoclimatology and our predictions of future global warming. Here, we use the ...inverse relationship between leaf stomatal indices and the partial pressure of CO2in modern Ginkgo biloba and Metasequoia glyptostroboides to develop a CO2reconstruction based on fossil Ginkgo and Metasequoia cuticles for the middle Paleocene to early Eocene and middle Miocene. Our reconstruction indicates that CO2remained between 300 and 450 parts per million by volume for these intervals with the exception of a single high estimate near the Paleocene/Eocene boundary. These results suggest that factors in addition to CO2are required to explain these past intervals of global warmth.
Understanding the link between the greenhouse gas carbon dioxide (CO.sub.2) and Earth's temperature underpins much of paleoclimatology and our predictions of future global warming. Here, we use the ...inverse relationship between leaf stomatal indices and the partial pressure of CO.sub.2 in modern Ginkgo biloba and Metasequoia glyptostroboides to develop a CO.sub.2 reconstruction based on fossil Ginkgo and Metasequoia cuticles for the middle Paleocene to early Eocene and middle Miocene. Our reconstruction indicates that CO.sub.2 remained between 300 and 450 parts per million by volume for these intervals with the exception of a single high estimate near the Paleocene/Eocene boundary. These results suggest that factors in addition to CO.sub.2 are required to explain these past intervals of global warmth.
Understanding the link between the greenhouse gas carbon dioxide (CO
2
) and Earth's temperature underpins much of paleoclimatology and our predictions of future global warming. Here, we use the ...inverse relationship between leaf stomatal indices and the partial pressure of CO
2
in modern
Ginkgo biloba
and
Metasequoia glyptostroboides
to develop a CO
2
reconstruction based on fossil
Ginkgo
and
Metasequoia
cuticles for the middle Paleocene to early Eocene and middle Miocene. Our reconstruction indicates that CO
2
remained between 300 and 450 parts per million by volume for these intervals with the exception of a single high estimate near the Paleocene/Eocene boundary. These results suggest that factors in addition to CO
2
are required to explain these past intervals of global warmth.
Most research investigating the paleoclimate is based on contemporary understanding of the relationship between carbon dioxide, a potent greenhouse gas, and the temperature of the planet. These ...issues are also critical for the development of accurate estimates of expected future warming. Researchers used the inverse relationship between leaf stomatal indices and the partial pressure of CO sub(2) in modern Ginkgo biloba and Metasequoia glyptostroboides to establish a reconstruction of historical CO sub(2) levels based on fossilized samples of Ginkgo and Metasequoia cuticles for the middle Paleocene to early Eocene and middle Miocene. Findings indicated that other factors beside CO sub(2) caused historical periods of global warming.
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