More notes ... =========== J Environ Sci (China). 2004;16(1):86-9.
An estimate on the rainout of atmospheric CO2.Ecology Center, University of Kiel, Schauenburgerstr 112, DE-24118 Kiel, Germany. cliu@ecology.uni-kiel.de
The CO2 in the atmosphere is in contact with water vapor and rain droplets forming CO2 x H2O, HCO3- and CO3(2-) . Global precipitation is about 505 x 1015 kg/a. Based on theoretical calculation for unpolluted air and measurement observations, we estimated that 100-270 x 10(12) gC/a are scavenged from the air by global precipitation.
This roughly equals carbon emissions from volcanic sources or 2-6 per cent of current CO2 emissions. An inventory-based estimate on carbon removal in northwestern Europe supports the above calculation on global scale. With increasing CO2 concentration in the air, precipitation scavenging may increase.
Arh Hig Rada Toksikol. 2007 Dec;58(4):479-86.
[Effects of volcanic eruptions on environment and health][Article in Croatian]
Sveuciliste u Zagrebu, Medicinski fakultet, Skola narodnog zdravlja, Zagreb, Hrvatska. ezuskin@snz.hr
Volcanoes pose a threat to almost half a billion people; today there are approximately 500 active volcanoes on Earth, and every year there are 10 to 40 volcanic eruptions.Volcanic eruptions produce hazardous effects for the environment, climate, and the health of the exposed persons, and are associated with the deterioration of social and economic conditions.
Along with magma and steam (H2O), the following gases surface in the environment: carbon dioxide (CO2) and sulphur dioxide (SO2), carbon monoxide (CO), hydrogen sulphide (H2S), carbon sulphide (CS), carbon disulfide (CS2), hydrogen chloride (HCl), hydrogen (H2), methane (CH4), hydrogen fluoride (HF), hydrogen bromide (HBr) and various organic compounds, as well as heavy metals (mercury, lead, gold).
Nature. 2000 Aug 17;406(6797):695-9.
Atmospheric carbon dioxide concentrations over the past 60 million years.Department of Earth Sciences, University of Bristol, UK. Paul.Pearson@Bristol.ac.uk
Knowledge of the evolution of atmospheric carbon dioxide concentrations throughout the Earth's history is important for a reconstruction of the links between climate and radiative forcing of the Earth's surface temperatures. Although atmospheric carbon dioxide concentrations in the early Cenozoic era (about 60 Myr ago) are widely believed to have been higher than at present, there is disagreement regarding the exact carbon dioxide levels, the timing of the decline and the mechanisms that are most important for the control of CO2 concentrations over geological timescales.
Here we use the boron-isotope ratios of ancient planktonic foraminifer shells to estimate the pH of surface-layer sea water throughout the past 60 million years, which can be used to reconstruct atmospheric CO2 concentrations. We estimate CO2 concentrations of more than 2,000 p.p.m. for the late Palaeocene and earliest Eocene periods (from about 60 to 52 Myr ago), and find an erratic decline between 55 and 40 Myr ago that may have been caused by reduced CO2 outgassing from ocean ridges, volcanoes and metamorphic belts and increased carbon burial.
Since the early Miocene (about 24 Myr ago), atmospheric CO2 concentrations appear to have remained below 500 p.p.m. and were more stable than before, although transient intervals of CO2 reduction may have occurred during periods of rapid cooling approximately 15 and 3 Myr ago.
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