Molecular fossils from phytoplankton reveal secular Pco2 trend over the Phanerozoic

by C.R. Witkowski et al., November28,  2018 in SciAdvances


Here, we reconstructed Phanerozoic PCO2 from a single proxy: the stable carbon isotopic fractionation associated with photosynthesis (Ɛp) that increases as PCO2 increases. This concept has been widely applied to alkenones, but here, we expand this concept both spatially and temporally by applying it to all marine phytoplankton via a diagenetic product of chlorophyll, phytane. We obtained data from 306 marine sediments and oils, which showed that Ɛp ranges from 11 to 24‰, agreeing with the observed range of maximum fractionation of Rubisco (i.e., 25 to 28‰). The observed secular PCO2 trend derived from phytane-based Ɛp mirrors the available compilations of PCO2over the past 420 Ma, except for two periods in which our higher estimates agree with the warm climate during those time periods. Our record currently provides the longest secular trend in PCO2 based on a single marine proxy, covering the past 500 Ma of Earth history

Fig. 2Ɛp calculated from phytane in Witkowski et al., 2018

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Man-Made Global Warming? Where’s The Evidence

by H. Schreuder, November 28, 2018 in ClimateChangeDipsatch


After decades of alarm calls over the impact of human emissions of carbon dioxide (CO2) on global temperatures and climate change, a glaring lack of factually demonstrated and scientifically proven evidence remains.

The evidence presented has been based on computer modeling of temperatures from global weather stations, a larger percentage of which are sited in towns and cities and no data, numerous studies show.

For the 70% of oceans, seas, and lakes, satellite measurements are routinely adjusted to take account of anomalies and sea level rise alarm, expressed in measurements of millimeters per century, does not quantify in that tidal gauges are subjected to landmass upheavals and/or subsidence, none of which can be taken to represent empirical evidence. See Also: New study shows coastlines gaining land despite sea level alarmism