We humans cannot release gaseous carbon skyward at the current rate without increasingly weakening the capacity of the land and the sea to sequester a portion of that airborne carbon. Eventually our pollution will “saturate” the ability of the land biosphere to drawdown heat-trapping carbon emissions from the atmosphere, which means that human caused fossil fuel emissions will coat our atmosphere at an even faster rate. Subsequent to the saturation of the terrestrial carbon sink, if our rate of emissions to the atmosphere is not slowed, we humans will trigger a worldwide carbon “sink-to-source switch” -- at which point the land biosphere will begin to vent carbon dioxide molecules into the atmosphere. This looming sink-to-source switch, a threshold response to unmitigated human pollution, will turn the land biosphere into a powerful engine of climate change and constitute “dangerous anthropogenic interference” with Earth’s climate system. Scientists know that we humans are pushing our planet's CO2 absorption capacities too far. The most vital task on Earth these days is to slow the pace at which heat-trapping chemical waste is coating our thin atmosphere.