Hi Greg, Yes, it is the balance between emissions and removal which has to be changed. Hansen says the CO2 level has to be at or below 350ppm, which is what it was thirty years ago - with 400ppm for the CO2eq level. The Earth System is extremely unlikely to return of its own accord to conditions of the Holocene norm, even with CO2 level reduced, because of what is happening in the Arctic. We can see from the history of the planet over the past few million years, how the Holocene was anomalously calm, and we can expect the Earth System to lurch towards violent change if it is not wrestled back towards the Holocene norm, with Arctic albedo as well as greenhouse gases restored to the levels they were, thirty years ago. Only then can we be confident of safe and sustainable conditions for future generations.
Cheers, John On Tue, Nov 10, 2015 at 7:09 PM, Greg Rau <gh...@sbcglobal.net> wrote: > More "permanence": > > http://www.commondreams.org/news/2015/11/09/overheated-planet-entering-uncharted-territory-frightening-speed > > "WMO Secretary-General Michel Jarraud said > <https://www.wmo.int/media/content/greenhouse-gas-concentrations-hit-yet-another-record> > this > means that we will "soon" be living with globally averaged CO2 levels above > the dangerous <http://climate.nasa.gov/400ppmquotes/>milestone of 400 ppm > <http://400.350.org/> "as a permanent reality." > > GR - is it just me, or aren't such statements forgetting that there is no > permanence to any given ppm, e.g, the CO2 ice core record; the intra annual > variation in ppm? The ppm is dictated by emissions versus removal, with > annual emissions currently beating removal by about 50%. Whether or not > humans can/will intervene to sufficiently change/manage this ratio dictates > a given CO2 trajectory or "permanence". Otherwise, barring a runaway > greenhouse, CO2 will eventually return to pre anthropogenic levels on > geologic time scales. Might we be able to hasten this decline in CO2? Might > air CO2 be actively managed by human intervention?- the answers will > determine the planet's "permanent reality". > > Sent from the Rau's iPad > > > > On Nov 9, 2015, at 3:55 PM, Greg Rau <gh...@sbcglobal.net> wrote: > > > https://scripps.ucsd.edu/programs/keelingcurve/2015/11/09/measurement-note-an-adjustment-to-the-record/ > "On Nov. 5, 2015, we made an adjustment to the Scripps Mauna Loa CO2 record > that has the effect of increasing concentrations we have reported since > April 2015 by 0.4 parts per million (ppm). We made the adjustment after > comparing our short-term calibration gases with the long-term calibration > gases, concentrations of which have been determined manometrically. > Comparing short- and long-term calibration gases is a normal part of the > strategy for maintaining reliable long-term measurements. The adjustment > increases the likelihood that concentrations will remain above 400 ppm > permanently after 2015." > *– Ralph Keeling* > GR - Unless air CO2 removal is increased and/or CO2 emissions are reduced. > -- > 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 geoengineering+unsubscr...@googlegroups.com. > To post to this group, send email to geoengineering@googlegroups.com. > Visit this group at http://groups.google.com/group/geoengineering. > For more options, visit https://groups.google.com/d/optout. > > -- > 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 geoengineering+unsubscr...@googlegroups.com. > To post to this group, send email to geoengineering@googlegroups.com. > Visit this group at http://groups.google.com/group/geoengineering. > For more options, visit https://groups.google.com/d/optout. > -- 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 geoengineering+unsubscr...@googlegroups.com. To post to this group, send email to geoengineering@googlegroups.com. Visit this group at http://groups.google.com/group/geoengineering. For more options, visit https://groups.google.com/d/optout.
