A former Manchester High School student is now traveling the world, studying stalagmites in caves for signs he says can predict future weather patterns. Charles Fishburne of 88.9 WCVE has more in this Science Matters report.
Every drop of rain leaves its signature on stalagmites buried deep in caves and Dr. James Baldini believes they can predict future weather patterns through the “chemistry of the drip.” Dr. Baldini, world renowned paleoclimatologist, went to Manchester High School then James Madison University to study chemistry, where he became enamored with caves. JMU is in the Shenandoah Valley which is riddled with caves and was the perfect environment for Baldini to combine his passion for chemistry with his love of the sport of caving. He changed his major to earth sciences and soon learned he could chart weather changes in the earth by studying the stalagmites he found in his caves.
I liked the idea of using chemistry to understand the earth and how things work on the planet. When you cut a stalagmite in half, essentially what you see is a pattern similar to tree rings.”
But whereas tree rings can date back only four hundred years, stalagmites can take us back up to half a million years, charting weather patterns all the way.
It’s more complex because you will get the chemistry of the stalagmite instead of just the width of the tree rings.”
The chemistry is important, because as it turns out, rain from hurricanes, for example has its own signature makeup. It means that a twenty thousand year old stalagmite can tell you not only when it rained, but also how much and what kind.
So what’s really, really neat about stalagmites is every single drip deposits just a little bit of calcium carbonate on the tip of the growing stalagmite,” states Baldini. “We can reconstruct the climate that has happened in the past and make predictions of climate change patterns.”
Baldini describes the process:
We saw the stalagmite in half lengthwise, and then sample some material (less than a gram) along the growth axis (where the drip would have hit - the center) at even intervals to date the sample. These powders are then run on a mass spectrometer to measure uranium and thorium isotope ratios which will then be used to determine the age of that particular powder sample. All of the dates are then combined to create a chronology. Then someone on the team will sample hundreds to thousands of spots to analyse for a variety of things. Generally we use isotopes of carbon and oxygen to create paleoclimate records, but the entire periodic table is possible. These are then placed in the appropriate place in time based on the chronology, and that is the climate record.”
Baldini explains that:
This will help us make predictions based on what we think will happen to temperature in the future.”
Among the things his stalagmites are telling him is that global warming is real.
Dr. Baldini is now Senior Lecturer in the Earth Science Department at Durham University in England and has been visiting his family in Powhatan this summer. He was recently featured in the Weather Channel’s program about the Collapse of the Mayan Civilization on their series “Weather That Changed the World.” You can learn more about Dr. Baldini and his wife, Dr. Lisa Baldini, also a paleoclimatologist in this PBS Newshour story “Stalagmites Provide Clues in Changing Rainfall Patterns.”
If you would like to know more about the study of caves and climate change check out this video.