Northern Morocco Holocene Speleothem d18O Data and Rainfall Index Ait Brahim, Y.; Wassenburg, J.A.; Sha, L.; Cruz, F.W.; Deininger, M.; Sifeddine, A.; Bouchaou, L.; Spötl, C.; Edwards, R.L.; Cheng, H. Ait Brahim, Y. Wassenburg, J.A. Sha, L. Cruz, F.W. Deininger, M. Sifeddine, A. Bouchaou, L. Spötl, C. Edwards, R.L. Cheng, H. Precipitation Reconstruction earth science/paleoclimate/reconstructions earth science/paleoclimate/speleothems (Grotte de Piste>LATITUDE 33.84>LONGITUDE -4.09) (Chaara Cave>LATITUDE 33.95>LONGITUDE -4.246) The North Atlantic Oscillation is the dominant atmospheric pressure mode in the North Atlantic region and affects winter temperature and precipitation in the Mediterranean, northwest Europe, Greenland, and Asia. The index that describes the sea-level pressure difference between Iceland and the Azores is correlated with a dipole precipitation pattern over northwest Europe and northwest Africa. How the North Atlantic Oscillation will develop as the Greenland ice sheet melts is unclear. A potential past analogue is the early Holocene, during which melting ice sheets around the North Atlantic freshened surface waters, affecting the strength of the meridional overturning circulation. Here we present a Holocene rainfall record from northwest Africa based on speleothem d18O and compare it against a speleothem-based rainfall record from Europe. The two records are positively correlated during the early Holocene, followed by a shift to an anti-correlation, similar to the modern record, during the mid-Holocene. On the basis of our simulations with an Earth system model, we suggest the shift to the anti-correlation reflects a large-scale atmospheric and oceanic reorganization in response to the demise of the Laurentide ice sheet and a strong reduction of meltwater flux to the North Atlantic, pointing to a potential sensitivity of the North Atlantic Oscillation to the melting of ice sheets. STUDY NOTES: Speleothem oxygen isotope (d18O) data and derived rainfall index for 3 speleothems from Northern Morrocco over the Holocene. NCDC-Paleoclimatology https://www.ncdc.noaa.gov/data-access/paleoclimatology-data - Bauer Bruce Investigator : Ait Brahim, Y. Investigator : Wassenburg, J.A. Investigator : Sha, L. Investigator : Cruz, F.W. Investigator : Deininger, M. Investigator : Sifeddine, A. Investigator : Bouchaou, L. Investigator : Spötl, C. Investigator : Edwards, R.L. Investigator : Cheng, H. 2019-07-04 ONLINE Files online, ASCII https://www.ncdc.noaa.gov/paleo/study/27150 https://www1.ncdc.noaa.gov/pub/data/paleo/speleothem/africa/grottedepiste2019d18o.txt https://www1.ncdc.noaa.gov/pub/data/paleo/speleothem/africa/chaara2019cha2d18o.txt https://www1.ncdc.noaa.gov/pub/data/paleo/speleothem/africa/chaara2019rain-index.txt https://www1.ncdc.noaa.gov/pub/data/paleo/speleothem/africa/chaara2019cha1d18o.txt https://www1.ncdc.noaa.gov/pub/data/paleo/speleothem/africa/grottedepiste2019d18o.txt https://www1.ncdc.noaa.gov/pub/data/paleo/speleothem/africa/chaara2019cha2d18o.txt https://www1.ncdc.noaa.gov/pub/data/paleo/speleothem/africa/chaara2019rain-index.txt https://www1.ncdc.noaa.gov/pub/data/paleo/speleothem/africa/chaara2019cha1d18o.txt English https://www.ncdc.noaa.gov/paleo/study/27150 https://www1.ncdc.noaa.gov/pub/data/paleo/speleothem/africa/grottedepiste2019d18o.txt https://www1.ncdc.noaa.gov/pub/data/paleo/speleothem/africa/chaara2019cha2d18o.txt https://www1.ncdc.noaa.gov/pub/data/paleo/speleothem/africa/chaara2019rain-index.txt https://www1.ncdc.noaa.gov/pub/data/paleo/speleothem/africa/chaara2019cha1d18o.txt Y. Ait Brahim, J.A. Wassenburg, L. Sha, F.W. Cruz, M. Deininger, A. Sifeddine, L. Bouchaou, Christoph Spotl, R.L. Edwards, H. Cheng2019North Atlantic Ice-Rafting, Ocean and Atmospheric Circulation During the Holocene: Insights From Western Mediterranean SpeleothemsGeophysical Research Letters10.1029/2019GL082405https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2019GL082405 Jasper A. Wassenburg, Stephan Dietrich, Jan Fietzke, Jens Fohlmeister, Klaus Peter Jochum, Denis Scholz, Detlev K. Richter, Abdellah Sabaoui, Christoph Spotl, Gerrit Lohmann, Meinrat O. Andreae, Adrian Immenhauser2016Reorganization of the North Atlantic Oscillation during Early Holocene deglaciationNature Geoscience10.1038/ngeo2767http://www.nature.com/ngeo/journal/vaop/ncurrent/full/ngeo2767.html START YEAR: 11787 cal yr BP * END YEAR: -58 cal yr BP -4.246 33.84 -4.09 33.95