The ECONorthwest team also tapped the American Community Survey data to look at current concentrations of low - income, non-white, and Hispanic populations within the valley. (bluum.org)
(I am not sure if he was referencing doubling from pre-industrial levels or doubling from current concentrations. (climate-skeptic.com)
Because most fluorinated gases have a very long atmospheric lifetime, it will take many years to see a noticeable decline in current concentrations. (epa.gov)