Wow, that slide presentation is a masterpiece in how to deceive engineers. He's not looking at it "as an engineer," he's looking at everything with preconceived notions and trying to cherry pick his way to his conclusion.
Basically all the "data" and arguments that he's presenting are cherry picked to be on the edge of plausibility, but as soon as you poke at them at all they fall part. It's really just a standard piece of denialist schlock.
For example on slide 4 look at his plot and compare to the wikipedia page:
https://en.wikipedia.org/wiki/Description_of_the_Medieval_Wa...
It's a bunch of canned and repeated arguments that are easily shot down, but doing each one takes so much time. It's like "debating" a creationist, shooting down an argument means that many more easily shot down arguments come right back up, with the denialist side somehow never loosing credibility while trying to assail the credibility of others.
If somebody finds that slide deck interesting, please read other data too, it's a completely biased picture, meant to trick people. Something balanced like the IPCC will be far more solid information, with proper citations, that can be backed up.
How could an organization dedicated to a topic filled with people who dedicated their life to said topic be trusted to have a balanced view of whether or not that topic has an impact? Just purely from a conflict of interest perspective, it seems similar to asking for a balanced view of religion from the 'international panel of priests and pastors'.
Climate scientists are not dedicated to advancing the idea of anthropogenic climate change, they are dedicated to studying the climate, where ever that leads them. If this were not true, then some of the contrarian scientists in the field would have much stronger criticisms of the work. As it is, their criticisms are relegated to rather minor details, without any good rebuttals of the primary thrust.
If you want to make the claim that the IPCC is not balanced on this, then there should be much stronger criticisms of the science in the IPCC, rather than the easily knocked down trivialities that appear in denialist memes.
The scaling of the "to inform, not to scare" graph to show "normal CO2 limits in a confined space" is particularly silly since afaik absolutely no climate scientist has ever speculated we're all about to suffocate from the additional carbon dioxide released.
I'm not entirely unsympathetic to his argument that climate forecasts are an inexact science, humanity is perfectly capable of living at higher average global temperatures and engineers might be better focusing attention on structural adjustment problems (like flooding and regional disruption to crops). But this is a polemic rather than a more compelling approach to reading the figures. And the idea mooted at the end that airline certification levels of certainty should be applied to all public policy decisions is just... amusing.