[blam]

"There hasn't been a large volcanic eruption since Pinatubo in 1991, which I suspect has contributed to some of the record warmth in recent years."

There is tree-ring data show pertubations after volcanos, I've seen these defined as cooling events. In fact, I thought all volcanoes caused some cooling. Am I wrong?

[Strategerist]

I meant the ABSENCE of large eruptions has contributed to global warmth recently; Pinatubo cooled the Northern hemisphere by about half a degree celsius; but 1991 is a long time ago.

There haven't even been any medium-sized, much less Pinatubo-sized, eruptions anywhere in the world in the last 15 years or so; thus you haven't been getting much sunlight blocked at all.