@article { ISI:000319344100038, title = {Annually Resolved Ice Core Records of Tropical Climate Variability over the Past similar to 1800 Years}, journal = {SCIENCE}, volume = {340}, number = {{6135}}, year = {2013}, month = {MAY 24}, pages = {945-950}, type = {Article}, abstract = {Ice cores from low Latitudes can provide a wealth of unique information about past climate in the tropics, but they are difficult to recover and few exist. Here, we report annually resolved ice core records from the Quelccaya ice cap (5670 meters above sea level) in Peru that extend back similar to 1800 years and provide a high-resolution record of climate variability there. Oxygen isotopic ratios (delta O-18) are linked to sea surface temperatures in the tropical eastern Pacific, whereas concentrations of ammonium and nitrate document the dominant role played by the migration of the Intertropical Convergence Zone in the region of the tropical Andes. Quetccaya continues to retreat and thin. Radiocarbon dates on wetland plants exposed along its retreating margins indicate that it has not been smaller for at least six millennia.}, issn = {0036-8075}, doi = {10.1126/science.1234210}, author = {Thompson, L. G. and Mosley-Thompson, E. and Davis, M. E. and Zagorodnov, V. S. and Howat, I. M. and Mikhatenko, V. N. and Lin, P. -N.} }