I believe You are correct, about the CFcs greanbean, it takes their molecules a long time, like 20-30 years? to difuse and migrate to the upper atmosphere and ozone layer. But not all countries in the world enforced the ban. It is still made for some foreign nations and in use today. But the largest portion of it's use has been suspended.
one thing to always consider it the power of large numbers. small things we do today, for better or worse, are multiplied by 6.6 billion. where as 2000 years ago the global population was closer to 100 million?
any small improvements in efficiency or per capita emissions reduction is easily overtaken by the growing human population. Equal to the rate of about the population of the USA every 4 1/2 years.
I have no idea how much CO2 the average person exhales per day, but just assuming our average methane belches are a meer one liter per day. that's 6.6 billion liters or 233 MCF of methane per day. or enough to run a 1400 megawatt state of the art combined cycle generating station round the clock. Methane is 21 times more effective as a green house gas as CO2. or equivalent to 5 BCF per day of CO2, plus what we exhale must be much more. Anybody know how much?
just one example of how our simple presence is a strong effect. collectively we can and are overwhelming the finite natural systems. So i'm not sure we can be carbon neutral anymore. We have converted too large a portion of the eco system to our carbon consumption use. for food, fuel and habitat. what's left can't keep up without deteriorating. Like the ocean. Getting more acidic.
but if we could go neutral, im sure the 383 ppm of co2 we currently have might eventually drop to a lower level. i doubt it would drop to pre industrial levels.
http://www.timesonline.co.uk/tol/new...cle2051364.ece
Not even mentioning COWS!!