noaa-lake-19160 Lago Umayo Isotope and Summary Diatom Data and Precipitation Reconstruction over the last 7000 years Baker, P.A.; Fritz, S.C. Lago Umayo Isotope and Summary Diatom Data and Precipitation Reconstruction over the last 7000 years 2015-08-26 NCDC-Paleoclimatology ONLINE Files Pending https://www.ncdc.noaa.gov/paleo/study/19160 Investigator P.A. Baker Investigator S.C. Fritz earth science paleoclimate paleolimnology total benthic diatoms,null,null,percent,null,paleolimnology,null,null,N,null earth science paleoclimate paleolimnology depth,null,null,centimeter,null,paleolimnology,null,null,N,null earth science paleoclimate paleolimnology notes,null,null,null,null,paleolimnology,null,null,C,null earth science paleoclimate paleolimnology total saline diatoms,null,null,percent,null,paleolimnology,null,null,N,null earth science paleoclimate paleolimnology total planktic diatoms,null,null,percent,null,paleolimnology,null,null,N,null earth science paleoclimate climate reconstructions|paleolimnology precipitation,delta 18O,null,meter per year,null,climate reconstructions|paleolimnology,null,null,N,null earth science paleoclimate paleolimnology age,null,null,calendar year before present,null,paleolimnology,null,null,N,null earth science paleoclimate paleolimnology delta 18O,calcium carbonate,null,per mil PDB,null,paleolimnology,null,null,N,null earth science paleoclimate paleolimnology reconstruction earth science paleoclimate paleolimnology oxygen isotopes earth science paleoclimate paleolimnology population abundance geoscientificInformation Precipitation Reconstruction 6656 cal yr BP 127 cal yr BP Complete -15.44 -15.44 -70.1 -70.1 3880 3880 Continent South America Peru Lago Umayo>LATITUDE -15.44>LONGITUDE -70.1 None Please cite original publication, online resource, dataset and publication DOIs (where available), and date accessed when using downloaded data. If there is no publication information, please cite investigator, title, online resource, and date accessed. The appearance of external links associated with a dataset does not constitute endorsement by the Department of Commerce/National Oceanic and Atmospheric Administration of external Web sites or the information, products or services contained therein. For other than authorized activities, the Department of Commerce/NOAA does not exercise any editorial control over the information you may find at these locations. These links are provided consistent with the stated purpose of this Department of Commerce/NOAA Web site. English DOC/NOAA/NESDIS/NCEI National Centers for Environmental Information, NESDIS, NOAA, U.S. Department of Commerce https://www.ncdc.noaa.gov/data-access/paleoclimatology-data DATA Center Contact Bruce Bauer bruce.a.bauer@noaa.gov paleo@noaa.gov 303-497-6280 303-497-6513

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Boulder CO 80305-3328 USA online ASCII Baker, P.A., S.C Fritz, S.J Burns, E. Ekdahl, C.A. Rigsby 2009 Developments in Paleoenvironmental Research 301-322 10.1007/978-90-481-2672-9_13 Ekdahl, E., S.C. Fritz, P.A. Baker, C.A. Rigsby, K. Coley 2008 The Holocene 18 867-876 10.1177/0959683608093524

This paper serves two purposes: to review current ideas about the nature and forcing of decadal to millennial scale precipitation variation in the southern tropics of South America during the late Quaternary and to present a new methodology for the reconstruction of precipitation as applied to a Holocene stable isotopic record of carbonate sediments in a tropical Andean lake, Lago Umayo, Peru. The basic thesis of the first part of the paper is that, although modern instrumental records suffice for deducing climate variability at decadal and shorter time scales, these records cannot adequately characterize the nature and forcing of lower-frequency climate variation. Understanding the nature of multi-decadal to millennial-scale climate variation and the mechanisms of large abrupt climate change is best derived from paleoclimatic time series. Tropical Atlantic sea-surface temperature variation is a significant control on tropical South American paleoclimate at these longer time scales. In the second part of the paper, an original method is presented for quantitatively reconstructing precipitation. This method utilizes the well-known relationship between the stable isotopic composition of precipitation and the amount of precipitation, a relationship that is highly significant in many tropical locales. Due to many simplifying assumptions, the reconstruction should be considered to be tentative. A ~12% increase in precipitation (~570 to 650 mm a –1) at 4750 cal year BP is consistent with the 6% increase in summer insolation at this latitude over the same period. However, the increase in precipitation was neither unidirectional nor gradual. Instead, every 240 years on average, precipitation increased or decreased by at least ~8% for periods lasting on average 100 years. The largest of these events had ~15% positive or negative departures from the long-term mean precipitation. These southern tropical wet events apparently coincided with periods of low sea-surface temperatures in the high-latitude North Atlantic, supporting a hypothesis of a tropical North Atlantic sea-surface temperature control on tropical South American precipitation at decadal to millennial scales. STUDY NOTES: diatom species data have been submitted to Neotoma. Precipitation is calculated from an isotope model; see paper for details. 14C dates were calibrated using Calib 5.0.2 (Stuiver and Reimer 1993) using the Southern Hemisphere calibration (McCormac et al. 2004). Provided Keywords: South America, tropics, Andes, SA monsoon, oxygen isotopes, carbonates, diatoms

GET DATA https://www1.ncdc.noaa.gov/pub/data/paleo/paleolimnology/southamerica/peru/baker2009/baker2009-lagoumayo.txt Formatted Text File; Lago Umayo Data USA/NOAA DIF Version 9.8.4 2018-12-11 2018-12-11