Anjohibe Cave, Madagascar 1700 Year Speleothem Stable Isotope Data Scroxton, N.; Burns, S.J.; McGee, D.; Hardt, B.F.; Godfrey, L.R.; Ranivoharimanana, L.; Faina, P. Scroxton, N. Burns, S.J. McGee, D. Hardt, B.F. Godfrey, L.R. Ranivoharimanana, L. Faina, P. Intertropical Convergence Zone (ITCZ) Monsoon earth science/paleoclimate/speleothems (delta 18O,calcium carbonate,null,per mil PDB,null,speleothems,averaged|interpolated,isotope ratio mass spectrometry,N,2 yr equally spaced interpolated record created in Matlab using a cubic hermite interpolating spline: mineralogy converted data interpolated to 2 month resolution then averaged to two year bins) earth science/paleoclimate/speleothems (depth,null,null,millimeter,null,speleothems,null,null,N,null) earth science/paleoclimate/speleothems (delta 18O,calcium carbonate,null,per mil VPDB,null,speleothems,raw,gas chromatography|isotope ratio mass spectrometry,N,null) earth science/paleoclimate/speleothems (calcite,calcium carbonate,null,percent,null,speleothems,raw,null,N,null) earth science/paleoclimate/speleothems (age,null,null,year Common Era,null,speleothems,null,null,N,U-Th series; Oxcal Age Model Software) earth science/paleoclimate/speleothems (age,null,null,year Common Era,null,speleothems,null,null,N,mid-point of two year bin) earth science/paleoclimate/speleothems (delta 13C,calcium carbonate,null,per mil VPDB,null,speleothems,raw,gas chromatography|isotope ratio mass spectrometry,N,null) earth science/paleoclimate/speleothems (delta 18O,calcium carbonate,null,per mil VPDB,null,speleothems,corrected,null,N,converted to 100% equivalent aragonite: raw value + (%calcite x 0.7permill)) earth science/paleoclimate/speleothems (delta 13C,calcium carbonate,null,per mil PDB,null,speleothems,averaged|interpolated,isotope ratio mass spectrometry,N,2 yr equally spaced interpolated record created in Matlab using a cubic hermite interpolating spline: mineralogy converted data interpolated to 2 month resolution then averaged to two year bins) earth science/paleoclimate/speleothems (delta 13C,calcium carbonate,null,per mil VPDB,null,speleothems,corrected,null,N,converted to 100% equivalent aragonite: raw value + (%calcite x 2.5permill)) earth science/paleoclimate/speleothems (age,null,two standard deviations,year,null,speleothems,null,null,N,Oxcal Age Model Software) earth science/paleoclimate/speleothems earth science/paleoclimate/speleothems (Anjohibe Cave>LATITUDE -15.53>LONGITUDE 46.88) Paleoclimate studies of tropical rainfall have led to a recognition of a predominant pattern of anti-phase behavior between the Northern and Southern hemispheres at both orbital and millennial timescales. Less certain is how regional tropical rainfall patterns have changed in the late Holocene, under boundary conditions and on timescales which are most relevant to the tropics' response to a warming world. Several high-resolution southern hemisphere rainfall records are at odds with meridional movement of the mean Inter-Tropical Convergence Zone location as the major driver of Holocene tropical rainfall variability, with regional precipitation patterns resembling modern day El-Niño Southern Oscillation end members. To test emerging ideas on sub-millennial tropical rainfall variability, additional records from the southern hemisphere are required. We present a new speleothem d18O record from Anjohibe Cave, northwestern Madagascar, which provides a quasi-annual record of monsoonal strength and precipitation amount for the last 1700 years. The majority of d18O variability in the record is at the decadal scale, and shows little to no correlation with major climate indices or cyclical climate drivers. At lower frequencies, changes in mean speleothem d18O show good correlation with other regional precipitation records both north and south of the equator. The regional coherency of tropical rainfall across the west Indian Ocean resembles expansion and contraction of the tropical rain belt and positive-Indian Ocean Dipole-like conditions at different timescales. The cause of this coherency could be related to symmetrical changes in continental sensible heating, or to a low frequency sea surface temperature climate mode. STUDY NOTES: Speleothem stable isotope (d18O and d13C) data from Anjohibe Cave, Madagascar for the past 1700 years as a record of the Madagascan monsoon. NCDC-Paleoclimatology https://www.ncdc.noaa.gov/data-access/paleoclimatology-data - Bauer Bruce Investigator : Scroxton, N. Investigator : Burns, S.J. Investigator : McGee, D. Investigator : Hardt, B.F. Investigator : Godfrey, L.R. Investigator : Ranivoharimanana, L. Investigator : Faina, P. 2017-04-10 ONLINE Files online, ASCII https://www.ncdc.noaa.gov/paleo/study/21850 https://www1.ncdc.noaa.gov/pub/data/paleo/speleothem/africa/anjohibe2017iso.txt https://www1.ncdc.noaa.gov/pub/data/paleo/speleothem/africa/anjohibe2017iso2yr.txt https://www1.ncdc.noaa.gov/pub/data/paleo/speleothem/africa/anjohibe2017iso.txt https://www1.ncdc.noaa.gov/pub/data/paleo/speleothem/africa/anjohibe2017iso2yr.txt English https://www.ncdc.noaa.gov/paleo/study/21850 https://www1.ncdc.noaa.gov/pub/data/paleo/speleothem/africa/anjohibe2017iso.txt https://www1.ncdc.noaa.gov/pub/data/paleo/speleothem/africa/anjohibe2017iso2yr.txt Nick Scroxton, Stephen J. Burns, David McGee, Ben Hardt, Laurie R. Godfrey, Lovasoa Ranivoharimanana, Peterson Faina2017Hemispherically in-phase precipitation variability over the last 1700 years in a Madagascar speleothem recordQuaternary Science Reviews16425-3610.1016/j.quascirev.2017.03.017http://www.sciencedirect.com/science/article/pii/S0277379116306734 START YEAR: 1567 cal yr BP * END YEAR: -63 cal yr BP 46.88 -15.53 46.88 -15.53