As a scientist (chemist) I find it most misleading for Mr. Brian Black to cite atmospheric gas levels obtained by new (only capable of low level measurements within the past 50 years) technologies over a 30 year period as evidence of change attributable to human activity.
The terms "climate change" or "global warming" indicate a measurable change between two data points fixed in time. These changes are deemed by some as everything from "troubling" to "apocalyptic." The terms imply a subjective value judgment, not unbiased objectivity. Scientifically, it begs the question "into what range of temperatures should the world fall"? And of course, the following question, "who determined this, based on what scientific evidence." Simply, when did the world's climate change, and what were the conditions at that point. I have yet to see these dates or scientifically verified data points proposed in any climate debate.
Using modern instrumentation capable of part-per-million, or part-per-billion sensitivity to prove a concept which may have been progressing over time is akin to comparing today's GPS accuracy to the compass and sextant of the sixteenth century in an attempt to make a valid point.
Unsubstantiated opinion should never be confused with scientifically obtained, challenged and validated fact.
Michael A. Glass, MS