Author(s):
Fuyuan Liang* - Western Illinois University
George A. Brook - University of Georgia
Abstract:
Variations in petrography, stable isotopes, gray color, and luminescence along the central growth axis of a 14.5 cm stalagmite from Panigarh Cave that was active when collected, provide a high resolution record of paleoenvironmental change for the Himalayan foothills of Northern India for the past 750 years. Deposition of calcite from AD 1480 to 1900 suggests a wetter and cooler Little Ice Age (LIA), while precipitation of aragonite during the periods from AD 1250 to 1480 and after AD 1900 indicates drier and warmer conditions at these times. Stalagmite d18O values from AD 1250 to 1780 show that the strength of the Indian summer monsoon varied only slightly in this period. However, large-amplitude variations in stalagmite d18O point to a variable monsoon climate after AD 1780, with two distinct periods of weak monsoon activity centered on AD 1800 and 1920. These periods are defined by significantly higher d18O values. Variations in stalagmite color and luminescence correlate well with estimates of changes in northern hemisphere temperature over the past 1000 years, with lighter colors and stronger luminescence corresponding with higher temperatures, and darker colors and reduced luminescence with lower temperatures.
