No tree rings after volcanic eruptions

Trees rings may not provide a full record of climate cooling as large enough temperature drops can lead to very short or absent growing seasons.

Each year, trees create unique growth rings reflecting weather conditions. But the short-term cooling following a large volcanic eruption isn’t always reflected in tree rings.

While the tree ring record is generally accurate, scientists uncovered discrepancies that correspond to large, tropical eruptions. Temperature drops were recorded three years after the eruptions. The absence of rings within three years of volcanic eruptions degrades tree ring temperature reconstructions.

Read more at Pennsylvania State University