noaa-model-16337 Paleoclimate Data-Model Comparison and the Role of Climate Forcings over the Past 1500 Years Phipps, S.J.; McGregor, H.V.; Gergis, J.; Gallant, A.J.E.; Neukom, R.; Stevenson, S.; Ackerley, D.; Brown, J.R.; Fischer, M.J.; van Ommen, T.D. Paleoclimate Data-Model Comparison and the Role of Climate Forcings over the Past 1500 Years 2014-03-18 NCDC-Paleoclimatology ONLINE Files Pending https://www.ncdc.noaa.gov/paleo/study/16337 Investigator S.J. Phipps Investigator H.V. McGregor Investigator J. Gergis Investigator A.J.E. Gallant Investigator R. Neukom Investigator S. Stevenson Investigator D. Ackerley Investigator J.R. Brown Investigator M.J. Fischer Investigator T.D. van Ommen earth science paleoclimate climate forcing carbon dioxide,null,null,parts per million,null,climate forcing,null,null,N,Equivalent CO2 concentration earth science paleoclimate climate forcing volcanic forcing,null,null,watt per square meter,null,climate forcing,null,null,N,null earth science paleoclimate paleoclimatic modeling latitude,null,null,degree north,null,paleoclimatic modeling,null,null,N,null earth science paleoclimate paleoclimatic modeling age,null,null,year Common Era,null,paleoclimatic modeling,null,null,N,null earth science paleoclimate climate forcing greenhouse gas forcing,null,null,watt per square meter,null,climate forcing,null,null,N,null earth science paleoclimate paleoclimatic modeling surface air temperature,null,null,kelvin,null,paleoclimatic modeling,null,null,N,null earth science paleoclimate paleoclimatic modeling evaporation,null,null,millimeter per day,null,paleoclimatic modeling,null,null,N,null earth science paleoclimate climate forcing solar irradiance,null,null,watt per square meter,null,climate forcing,null,null,N,null earth science paleoclimate paleoclimatic modeling precipitation,null,null,millimeter per day,null,paleoclimatic modeling,null,null,N,null earth science paleoclimate paleoclimatic modeling longitude,null,null,degree east,null,paleoclimatic modeling,null,null,N,null earth science paleoclimate paleoclimatic modeling sea level pressure,null,null,hectopascal,null,paleoclimatic modeling,null,null,N,null earth science paleoclimate paleoclimatic modeling salinity,sea surface,null,practical salinity unit,null,paleoclimatic modeling,null,null,N,null earth science paleoclimate paleoclimatic modeling sea surface temperature,null,null,degree Celsius,null,paleoclimatic modeling,null,null,N,null earth science paleoclimate model atmosphere model earth science paleoclimate model ocean model geoscientificInformation 1 AD 2000 AD 1949 cal yr BP -50 cal yr BP Complete -90 90 -180 180 Geographic Region Global Global>LATITUDE >LONGITUDE 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 Steven J. Phipps, Helen V. McGregor, Joëlle Gergis, Ailie J.E. Gallant, Raphael Neukom, Samantha Stevenson, Duncan Ackerley, Josephine R. Brown, Matt J. Fischer, and Tas D. van Ommen 2013 Journal of Climate 26 18 6915-6936 10.1175/JCLI-D-12-00108.1 http://journals.ametsoc.org/doi/abs/10.1175/JCLI-D-12-00108.1

The past 1500 years provide a valuable opportunity to study the response of the climate system to external forcings. However, the integration of paleoclimate proxies with climate modeling is critical to improving the understanding of climate dynamics. In this paper, a climate system model and proxy records are therefore used to study the role of natural and anthropogenic forcings in driving the global climate. The inverse and forward approaches to paleoclimate data-model comparison are applied, and sources of uncertainty are identified and discussed. In the first of two case studies, the climate model simulations are compared with multiproxy temperature reconstructions. Robust solar and volcanic signals are detected in Southern Hemisphere temperatures, with a possible volcanic signal detected in the Northern Hemisphere. The anthropogenic signal dominates during the industrial period. It is also found that seasonal and geographical biases may cause multiproxy reconstructions to overestimate the magnitude of the long-term preindustrial cooling trend. In the second case study, the model simulations are compared with a coral δ18O record from the central Pacific Ocean. It is found that greenhouse gases, solar irradiance, and volcanic eruptions all influence the mean state of the central Pacific, but there is no evidence that natural or anthropogenic forcings have any systematic impact on El Niño-Southern Oscillation. The proxy climate relationship is found to change over time, challenging the assumption of stationarity that underlies the interpretation of paleoclimate proxies. These case studies demonstrate the value of paleoclimate data-model comparison but also highlight the limitations of current techniques and demonstrate the need to develop alternative approaches. STUDY NOTES: Simulations of the climate of the past 2000 years, conducted using the CSIRO Mk3L climate system model version 1.2.

GET DATA https://www1.ncdc.noaa.gov/pub/data/paleo/gcmoutput/phipps2014/phipps2014-readme.txt Formatted Text File; Readme File GET DATA https://www1.ncdc.noaa.gov/pub/data/paleo/gcmoutput/phipps2014/phipps2014-forcing.txt Formatted Text File; Forcing Data Used GET DATA https://www1.ncdc.noaa.gov/pub/data/paleo/gcmoutput/phipps2014/ Data Folder; netCDF Output Files USA/NOAA DIF Version 9.8.4 2018-12-11 2018-12-11