{"NOAAStudyId":"11928","contactInfo":{"address":"325 Broadway, E/NE31","city":"Boulder","constraints":"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.","country":"USA","dataCenterUrl":"https://www.ncdc.noaa.gov/data-access/paleoclimatology-data","email":"paleo@noaa.gov","fax":"303-497-6513","longName":"National Centers for Environmental Information, NESDIS, NOAA, U.S. Department of Commerce ","phone":"303-497-6280","postalCode":"80305-3328","shortName":"DOC/NOAA/NESDIS/NCEI","state":"CO","type":"CONTACT INFORMATION"},"contributionDate":"2011-08-23","dataPublisher":"NOAA","dataType":"CLIMATE RECONSTRUCTIONS","dataTypeInformation":"https://www.ncdc.noaa.gov/data-access/paleoclimatology-data/datasets/climate-reconstruction","difMetadataLink":"http://www1.ncdc.noaa.gov/pub/data/metadata/published/paleo/dif/xml/noaa-recon-11928.xml","doi":null,"earliestYearBP":10200,"earliestYearCE":-8250,"entryId":"noaa-recon-11928","funding":[{"fundingAgency":"ANR France","fundingGrant":"SAHELP"}],"investigators":"Lézine, A.-M.; Hély, C.; Grenier, C.; Braconnot, P.; Krinner, G.","mostRecentYearBP":1500,"mostRecentYearCE":450,"onlineResourceLink":"https://www.ncdc.noaa.gov/paleo/study/11928","originalSource":null,"publication":[{"abstract":"The examination of more than 1500 paleohydrological dated records \r\ncollected between 10 and 28°N during the last 50 years have been \r\nused to improve our knowledge and understanding of the Sahara \r\nand Sahel vulnerability to the Atlantic monsoon changes in the \r\nlong-term. We have analyzed the distribution of water bodies \r\n(mainly lakes and wetlands) over time and space: the central \r\nSaharan massifs played a major role in favoring water supply \r\nto the lowlands throughout the whole African Humid Period. \r\nIn addition, distinct East-West dynamics is recorded with \r\nhumidity starting - and stopping - several millennia earlier \r\nto the east than to the west of the Sahara. \r\n\r\nA series of time lags are discussed: (1) between the maximum \r\nof deep (fresh water) lake formation during the early Holocene \r\nand the maximum of water body extensions during the mid-Holocene \r\nwhich highlight the primary role of aquifer water level in lake \r\nresponse to climate change (2) between the hydrological history \r\nof the Sahara and the Sahel and the forcings - mainly insolation \r\nchanges - during the early and mid-Holocene which involves complex \r\ninteractions between remnant ice sheet in the Northern Hemisphere, \r\nopen water bodies in the Sahara and Sahel and the Atlantic monsoon \r\nsystem. \r\n\r\n\r\n","author":null,"citation":"Lézine, A.-M., C. Hély, C. Grenier, P. Braconnot, \r\nand G. Krinner. 2011. \r\nSahara and Sahel vulnerability to climate changes, \r\nlessons from Holocene hydrological data. \r\nQuaternary Science Reviews. doi:10.1016/j.quascirev.2011.07.006 \r\n","edition":null,"identifier":{"id":"10.1016/j.quascirev.2011.07.006 ","type":"doi","url":"http://dx.doi.org/10.1016/j.quascirev.2011.07.006 "},"issue":null,"journal":"Quaternary Science Reviews","pages":null,"pubRank":"1","pubYear":2011,"reportNumber":null,"title":"Sahara and Sahel vulnerability to climate changes,  lessons from Holocene hydrological data","type":"publication","volume":null}],"reconstruction":"Y","scienceKeywords":["Other Hydroclimate Reconstruction","hydrology"],"site":[{"NOAASiteId":"9375","geo":{"geoType":"Feature","geometry":{"coordinates":["20.3","9.03"],"type":"POINT"},"properties":{"easternmostLongitude":"9.03","maxElevationMeters":null,"minElevationMeters":null,"northernmostLatitude":"20.3","southernmostLatitude":"20.3","westernmostLongitude":"9.03"}},"locationName":"Continent>Africa>Western Africa>Niger","mappable":"Y","paleoData":[{"NOAADataTableId":"20248","coreLengthMeters":null,"dataFile":[{"NOAAKeywords":["earth science>paleoclimate>reconstructions>lake level"],"fileUrl":"https://www1.ncdc.noaa.gov/pub/data/paleo/paleolimnology/africa/sahara-sahel2011hydro.txt","linkText":"sahara-sahel2011hydro.txt","urlDescription":"Data","variables":[{"cvAdditionalInfo":"SiteName","cvDataType":"CLIMATE RECONSTRUCTIONS|LAKE LEVELS|OTHER COLLECTIONS|PALEOLIMNOLOGY","cvDetail":null,"cvError":null,"cvFormat":"Character","cvMaterial":null,"cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":null,"cvWhat":"sampling metadata>sample identification"},{"cvAdditionalInfo":"Country","cvDataType":"CLIMATE RECONSTRUCTIONS|LAKE LEVELS|OTHER COLLECTIONS|PALEOLIMNOLOGY","cvDetail":null,"cvError":null,"cvFormat":"Character","cvMaterial":null,"cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":null,"cvWhat":"sampling metadata>notes"},{"cvAdditionalInfo":"CountryCode","cvDataType":"CLIMATE RECONSTRUCTIONS|LAKE LEVELS|OTHER COLLECTIONS|PALEOLIMNOLOGY","cvDetail":null,"cvError":null,"cvFormat":"Character","cvMaterial":null,"cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":null,"cvWhat":"sampling metadata>notes"},{"cvAdditionalInfo":"County","cvDataType":"CLIMATE RECONSTRUCTIONS|LAKE LEVELS|OTHER 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COLLECTIONS|PALEOLIMNOLOGY","cvDetail":null,"cvError":null,"cvFormat":"Character","cvMaterial":null,"cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":null,"cvWhat":"sampling metadata>sample identification"},{"cvAdditionalInfo":null,"cvDataType":"LAKE LEVELS|PALEOLIMNOLOGY","cvDetail":"raw","cvError":null,"cvFormat":"Character","cvMaterial":null,"cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"dimensionless","cvWhat":"earth system variable>hydrographic variable>lake level"},{"cvAdditionalInfo":null,"cvDataType":"CLIMATE RECONSTRUCTIONS|LAKE LEVELS|OTHER COLLECTIONS|PALEOLIMNOLOGY","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":null,"cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"degree north","cvWhat":"sampling metadata>latitude"},{"cvAdditionalInfo":null,"cvDataType":"CLIMATE RECONSTRUCTIONS|LAKE LEVELS|OTHER COLLECTIONS|PALEOLIMNOLOGY","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":null,"cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"degree east","cvWhat":"sampling metadata>longitude"},{"cvAdditionalInfo":null,"cvDataType":"CLIMATE RECONSTRUCTIONS|LAKE LEVELS|OTHER COLLECTIONS|PALEOLIMNOLOGY","cvDetail":null,"cvError":null,"cvFormat":"Numeric","cvMaterial":null,"cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"radiocarbon year before present","cvWhat":"age variable>age"},{"cvAdditionalInfo":null,"cvDataType":"CLIMATE RECONSTRUCTIONS|LAKE LEVELS|OTHER COLLECTIONS|PALEOLIMNOLOGY","cvDetail":null,"cvError":"one standard deviation","cvFormat":"Numeric","cvMaterial":null,"cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"radiocarbon year before present","cvWhat":"age variable>age"},{"cvAdditionalInfo":null,"cvDataType":"CLIMATE RECONSTRUCTIONS|LAKE LEVELS|OTHER COLLECTIONS|PALEOLIMNOLOGY","cvDetail":null,"cvError":"unspecified error lower bound","cvFormat":"Numeric","cvMaterial":null,"cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"calendar kiloyear before present","cvWhat":"age variable>age"},{"cvAdditionalInfo":null,"cvDataType":"CLIMATE RECONSTRUCTIONS|LAKE LEVELS|OTHER COLLECTIONS|PALEOLIMNOLOGY","cvDetail":null,"cvError":"unspecified error upper bound","cvFormat":"Numeric","cvMaterial":null,"cvMethod":null,"cvSeasonality":null,"cvShortName":null,"cvUnit":"calendar kiloyear before present","cvWhat":"age variable>age"}]},{"NOAAKeywords":["earth science>paleoclimate>reconstructions>lake level"],"fileUrl":"https://www1.ncdc.noaa.gov/pub/data/paleo/paleolimnology/africa/sahara-sahel2011hydro.xls","linkText":"sahara-sahel2011hydro.xls","urlDescription":"Data","variables":[]}],"dataTableName":"SSHPD","dataTableNotes":null,"earliestYear":10200,"earliestYearBP":10200,"earliestYearCE":-8250,"mostRecentYear":1500,"mostRecentYearBP":1500,"mostRecentYearCE":450,"species":[],"timeUnit":"cal yr BP"}],"siteName":"Adrar Bous"}],"studyCode":null,"studyName":"Sahara-Sahel Holocene Paleohydrological Database","studyNotes":"Database of Holocene paleohydrological reconstructions derived \nfrom published sources for the Sahara and Sahel, 10°N to 28°N. \nThe former extent of lakes, wetlands and rivers can be \nreconstructed by a variety of paleolimnological evidence \nincluding abandoned shorelines, sediment outcrops, aquatic \npollen types from sediment cores, remains of aquatic faunas \nsuch as hippos, fishes and shells, and former fluvial terraces. \nPaleohydrological variations can also be inferred from \npaleosalinity reconstructions from micro-faunal assemblages \n(diatoms, chironomids, ostracods) and stable isotope ratios \nin carbonates.  This data set is composed of 1688 dated samples \nfrom about 415 localities in the present day Sahara and Sahel, \nextracted from original published studies. \n\nThe file has been slightly modified from the original version \nused for the paper: new references have been included, \nand unpublished data have been removed. \n","version":"1.0","xmlId":"10031"}