Growth bands are visible in a polished cross-section of a stalagmite from
Based on chemical signatures in a piece of calcite from a cave near
The researchers, led by UW-Madison geology graduate student Ian Orland and professor
…Using oxygen isotope signatures and impurities — such as organic matter flushed into the cave by surface rain — trapped in the layered mineral deposits, Orland determined annual rainfall levels for the years the stalagmite was growing, from approximately 200 B.C. to 1100 A.D. Their detailed climate record shows that the
Growth bands are visible in a polished cross-section of a stalagmite from Soreq Cave near Jerusalem, Israel. Geochemical analysis of a similar stalagmite from the same cave has revealed that large climate changes in the Eastern Mediterranean 1,400 years ago, including increasingly dry weather from 100 A.D. to 700 A.D., may have contributed to the downfall of the Roman and Byzantine Empires in the region.