SPELEOTHEM RECORDS OF GREAT BASIN HYDROCLIMATE DURING THE LAST TWO GLACIAL TERMINATIONS AND INTERGLACIALS

The availability of stalagmite records in the western US is steadily increasing, providing new opportunities to extend hydroclimate reconstructions beyond the most recent glacial-interglacial cycle. This expansion of records increases the importance of establishing firm connections between stalagmite proxy data and hydroclimate outside the cave. Here we examine trace element behavior in soils, drip waters and stalagmites from Lehman Cave in Nevada to better understand the ways in which climate changes might be recorded in stalagmites from the region. We then present trace element and stable isotope records from stalagmites covering the last two terminations and interglacials, comparing them whenever possible with complementary data from other regional paleoclimate archives. Our results help document similarities and differences in the local hydrological response to the last two glacial terminations and interglacials. These results offer insight into the relative importance of a variety of potential influences – including orbital changes, ice sheet size, and abrupt changes in ocean circulation – in shaping the region’s hydroclimate, as well as the variable sensitivities of different paleoclimate proxies to past climate changes.