IIRC NOx is also a strong greenhouse gas, stronger than CO2 by a good factor. Shorter halflife, but if it helps bump AGW to tipping points then halflives don't matter anymore.
On 27 September 2015 18:44:00 IST, jim bell <[email protected]> wrote: > From: Georgi Guninski <[email protected]> >http://www.theregister.co.uk/2015/09/25/vw_pollution_just_the_tip_of_the_iceberg_whos_to_blame_you_guessed_it_hippies/ > >><quote> >>Volkswagen is being rightly condemned from all directions, as its >>methods were particularly cynical: its engine software would sense >when >>the car was in a test environment and cut back NO_x output >temporarily. > >>As soon as the car was no longer under test, the car would change mode >>and emit huge amounts of NO_x. This wasn't done for no reason – if a >>machine is allowed to generate NO_x freely, it can be very >>fuel-efficient – and thus, of course, its carbon emissions can be very >>low too. > >I noticed that (at least!) one media report portrayed this as making >VW's less "green". But from another report, I saw that they had 10% >greater gas mileage if they were allowed to cheat. (In other words, >less CO2 emissions per mile.) Now, the above quote refers to "huge >amounts" of NOx. (nitrogen oxides, probably NO and NO2). The question >is, for those people who complain about CO2 being a greenhouse gas, >what is the relative undesireability of extra CO2 versus extra NOx. > Relative harm, and all that. Which is a concept that people who call >themselves "environmentalists" seem to have a great deal of difficulty >with. >This also raises an idea: I've never heard of this, but what would be >wrong with allowing differences in emissions based on location? > Putting a GPS in a car is trivial today. Producing less NOx inside a >city would make sense; producing less NOx while on a cross-country >road-trip less so. Jim Bell -- Sent from my Android device with K-9 Mail. Please excuse my brevity.
