Yesterday I have written a question and answer play. Any comments? Olaf Schuiling, R.D. (Olaf)
Layman questions to be answered by geologists R.D.Schuiling Q: Volcanoes emit every year a sizable volume of CO2. Does that all remain in the atmosphere and the oceans? A: Fortunately not. If all that CO2 had stayed in the atmosphere and oceans, the Earth would now have an atmosphere with a CO2 pressure around 100 bar, and a surface temperature of 500 degrees centigrade, making life impossible. Q: Where did that CO2 go? A.: Have you ever walked in the Dolomites or sailed along the Cliffs of Dover? Those enormous masses of dolomite or calcite carry million times more CO2 than contained in the atmosphere, the oceans and the biosphere together. Q: But how did it get there? A: By two processes. First water and CO2 react with basic silicates, by which bicarbonate solutions are formed. That process is called weathering. Then these solutions are carried by rivers to the sea, where corals, shellfish and plankton turn it into limestones and dolomites. Those are the safe and sustainable CO2 storage rooms of nature. Q: So we don't have to do anything, these processes will take care of the problem? A: On the contrary, we have a lot to do. Presently we emit fifty to hundred times more CO2 than is normally emitted by volcanoes. That causes a rapid rise of the CO2 level of the atmosphere (400.3 ppm beginning of February 2015). It also causes a lowering of the pH of the oceans. This emission is caused by the fact that we burn in a few hundred years all the fossil fuels that have taken hundreds of millions of years to form. Weathering is too slow to cope with this increased emission. Q: Can't we increase the rate of weathering, to restore the balance between input and output? A: That is possible. We must look for common rocks (like olivine rocks) that weather easily. We must mine those rocks, mill them and spread the grains over fields, beaches and shallow seas (and even in sandboxes in nursery schools). Q: Why don't we start doing it? A: Because it costs money, and every country tries to shift the burden. Maybe we need a climate catastrophe before anything is done to avert climate change. Q: But what must we do when the olivine is finished? A: The olivine will never be finished, there is much more olivine in huge massifs in many countries on every continent than we will ever need for solving the climate change problem. Q: There is no life on our sister planet Venus. Its atmosphere has a CO2 pressure of 75 bars, and its surface temperature is 465 degrees centigrade. Why does it not work there? A: Because there is no liquid water on Venus, and that is a necessary condition for weathering Q: So we owe our existence to water and weathering? A: Yes -- You received this message because you are subscribed to the Google Groups "geoengineering" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/geoengineering. For more options, visit https://groups.google.com/d/optout.
