Journal cover Journal topic
Climate of the Past An interactive open-access journal of the European Geosciences Union
© Author(s) 2017. This work is distributed under
the Creative Commons Attribution 3.0 License.
Review article
07 Apr 2017
Review status
This discussion paper is under review for the journal Climate of the Past (CP).
Comparing proxy and model estimates of hydroclimate variability and change over the Common Era
Jason E. Smerdon1, Jürg Luterbacher2,3, Steven J. Phipps4, Kevin J. Anchukaitis5, Toby Ault6, Sloan Coats7,8, Kim M. Cobb9, Benjamin I. Cook1,10, Chris Colose10, Thomas Felis11, Ailie Gallant12, Johann H. Jungclaus13, Bronwen Konecky8, Allegra LeGrande10, Sophie Lewis14, Alex S. Lopatka15, Wenmin Man16, Justin S. Mankin1,10, Justin T. Maxwell17, Bette L. Otto-Bliesner7, Judson W. Partin18, Deepti Singh1, Nathan J. Steiger1, Samantha Stevenson7, Jessica E. Tierney19, Davide Zanchettin20, Huan Zhang2, Alyssa R. Atwood9,21, Laia Andreu-Hayles1, Seung H. Baek1, Brendan Buckley1, Edward R. Cook1, Rosanne D'Arrigo1, Sylvia G. Dee22, Michael Griffiths23, Charuta Kulkarni24, Yochanan Kushnir1, Flavio Lehner7, Caroline Leland1, Hans W. Linderholm25, Atsushi Okazaki26, Jonathan Palmer27, Eduardo Piovano28, Christoph C. Raible29, Mukund P. Rao1, Jacob Scheff1, Gavin A. Schmidt10, Richard Seager1, Martin Widmann30, A. Park Williams1, and Elena Xoplaki2 1Lamont-Doherty Earth Observatory of Columbia University, Palisades, NY, USA
2Department of Geography, Climatology, Climate Dynamics and Climate Change, Justus Liebig University of Giessen, Giessen, Germany
3Centre for International Development and Environmental Research, Justus Liebig University Giessen, Giessen, Germany
4Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, Tasmania, Australia
5School of Geography and Development and Laboratory of Tree Ring Research, University of Arizona, Tucson, AZ, USA
6Department of Earth and Atmospheric Sciences, Cornell University, Ithaca, NY, USA
7National Center for Atmospheric Research, Boulder, CO, USA
8Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA
9Department of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, GA, USA
10NASA Goddard Institute for Space Studies, New York, NY, USA
11MARUM – Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany
12School of Earth, Atmosphere and Environment, Monash University, Melbourne, Australia
13Max-Planck-Institute for Meteorology, Hamburg, Germany
14Fenner School of Environment and Society, The Australian National University, Canberra, ACT, Australia
15Department of Geology, University of Maryland, College Park, MA, USA
16LASG, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, China
17Department of Geography, Indiana University, Bloomington, IN, USA
18Institute for Geophysics, Jackson School of Geosciences, University of Texas at Austin, Austin, TX, USA
19Department of Geosciences, University of Arizona, Tucson, AZ, USA
20Department of Environmental Sciences, Informatics and Statistics, Ca' Foscari University of Venice, Venice, Italy
21Department of Geography, University of California, Berkeley, Berkeley, CA, USA
22Department of Earth, Environmental, and Planetary Sciences, Brown University, Providence, RI, USA
23Department of Environmental Science, William Paterson University, Wayne, NJ, USA
24Department of Earth and Environmental Sciences, The Graduate Center, City University of New York, New York, NY, USA
25Regional Climate Group, Department of Earth Sciences, University of Gothenburg, Gothenburg, Sweden
26Atmosphere and Ocean Research Institute, University of Tokyo, Tokyo, Japan
27Palaeontology, Geobiology and Earth Archives Research Centre, School of Biological, Earth and Environmental Sciences, University of New South Wales, Australia
28Centro de Investigaciones en Ciencias de la Tierra (CICTERRA / CONICET – Universidad Nacional de Córdoba), Córdoba, Argentina
29Climate and Environmental Physics, Physics Institute and Oeschger Centre for Climate Change Research, University of Bern, Bern, Switzerland
30School of Geography, Earth and Environmental Sciences, University of Birmingham, Birmingham, UK
Abstract. Water availability is fundamental to societies and ecosystems, but our understanding of variations in hydroclimate (including extreme events, flooding, and decadal periods of drought) is limited because of a paucity of modern instrumental observations that are distributed unevenly across the globe and only span parts of the 20th and 21st centuries. Such data coverage is insufficient for characterizing hydroclimate and its associated dynamics because of its multidecadal-to-centennial variability and highly regionalized spatial signature. High-resolution (seasonal to decadal) hydroclimatic proxies that span all or parts of the Common Era (CE) and paleoclimate model simulations are therefore important tools for augmenting our understanding of hydroclimate variability. In particular, the comparison of the two sources of information is critical for addressing the uncertainties and limitations of both, while enriching each of their interpretations. We review the principal proxy data available for hydroclimatic reconstructions over the CE and highlight contemporary understanding of how these proxies are interpreted as hydroclimate indicators. We also review the available last-millennium simulations from fully-coupled climate models and discuss several outstanding challenges associated with simulating hydroclimate variability and change over the CE. A specific review of simulated hydroclimatic changes forced by volcanic events is provided, as well as a discussion of expected improvements in estimated forcings, models and their implementation in the future. Our review of hydroclimatic proxies and last-millennium model simulations is used as the basis for articulating a variety of considerations and best practices for how to perform proxy-model comparisons of CE hydroclimate. This discussion provides a framework for how best to evaluate hydroclimate variability and its associated dynamics using these comparisons, as well as how they can better inform interpretations of both proxy data and model simulations. We subsequently explore means of using proxy-model comparisons to better constrain and characterize future hydroclimate risks. This is explored specifically in the context of several examples that demonstrate how proxy-model comparisons can be used to quantitatively constrain future hydroclimatic risks as estimated from climate model projections.

Citation: Smerdon, J. E., Luterbacher, J., Phipps, S. J., Anchukaitis, K. J., Ault, T., Coats, S., Cobb, K. M., Cook, B. I., Colose, C., Felis, T., Gallant, A., Jungclaus, J. H., Konecky, B., LeGrande, A., Lewis, S., Lopatka, A. S., Man, W., Mankin, J. S., Maxwell, J. T., Otto-Bliesner, B. L., Partin, J. W., Singh, D., Steiger, N. J., Stevenson, S., Tierney, J. E., Zanchettin, D., Zhang, H., Atwood, A. R., Andreu-Hayles, L., Baek, S. H., Buckley, B., Cook, E. R., D'Arrigo, R., Dee, S. G., Griffiths, M., Kulkarni, C., Kushnir, Y., Lehner, F., Leland, C., Linderholm, H. W., Okazaki, A., Palmer, J., Piovano, E., Raible, C. C., Rao, M. P., Scheff, J., Schmidt, G. A., Seager, R., Widmann, M., Williams, A. P., and Xoplaki, E.: Comparing proxy and model estimates of hydroclimate variability and change over the Common Era, Clim. Past Discuss.,, in review, 2017.
Jason E. Smerdon et al.
Jason E. Smerdon et al.
Jason E. Smerdon et al.


Total article views: 1,170 (including HTML, PDF, and XML)

HTML PDF XML Total BibTeX EndNote
811 316 43 1,170 4 41

Views and downloads (calculated since 07 Apr 2017)

Cumulative views and downloads (calculated since 07 Apr 2017)

Viewed (geographical distribution)

Total article views: 1,170 (including HTML, PDF, and XML)

Thereof 1,162 with geography defined and 8 with unknown origin.

Country # Views %
  • 1



Latest update: 22 Jun 2017
Publications Copernicus
Short summary
Water availability is fundamental to societies and ecosystems, but our understanding of variations in hydroclimate (including extreme events, flooding, and decadal periods of drought) is limited due to a paucity of modern instrumental observations. We review how proxy records of past climate and climate model simulations can be used in tandem to understand hydroclimate variability over the last 2000 years and how these tools can also inform risk assessments of future hydroclimatic extremes.
Water availability is fundamental to societies and ecosystems, but our understanding of...