Hurricane history from tree rings

From the Earth System Processes 2 meeting comes an interesting method of tracking past hurricanes using tree growth rings.

Centuries of hurricane records have been discovered in the rings of southeastern US pine trees. This arboreal archive may contain critical information about how the Atlantic hurricane factory responds over the long term to natural and human-induced climate changes, say researchers at the University of Tennessee, Knoxville.

Apparently a record of past tropical storms and hurricanse can be gleaned by looking at the O-18 concentration in tree growth rings.

What makes drops in oxygen-18 so telling is that it matches up with a little known talent of all hurricanes: they are very good at depleting the air of oxygen-18, Mora says. Consequently, there are unusually low concentrations of oxygen-18 in the water that rains out of hurricanes. So when shallow roots of Southeastern trees like the longleaf pine and slash pine suck up that low-O-18 hurricane rain water, the same unusual isotopic signal is preserved in the woody tree cells that start growing as soon as the sun breaks through the storm clouds.

Neat stuff. Who knew trees could store all this interesting information.

Found via ScienceDaily.