• Cayan, D. R., S. A.Kammerdiener, M. D.Dettinger, J. M.Caprio, and D. H.Peterson (2001), Changes in the onset of spring in the western United States, Bull. Am. Meteorol. Soc., 82, 399415.
  • Cleveland, W. S. (1979), Robust locally weighted regression and smoothing scatterplots, J. Am. Stat. Assoc., 74(368), 829836.
  • Cook, B. I., R. L.Miller, and R.Seagera (2009), Amplification of the North American “Dust Bowl” drought through human-induced land degradation, Proc. Natl. Acad. Sci. U. S. A., 106(13), 49975001, doi:10.1073/pnas.0810200106.
  • Diamond, H. J., et al. (2012), U.S. Climate Reference Network: The gold standard for surface climate observations in the U.S.—A decade of accomplishments, Bull. Am. Meteorol. Soc., in press.
  • Easterling, D. R., T. W. R.Wallis, J. H.Lawrimore, and R. R.HeimJr. (2007), Effects of temperature and precipitation trends on U.S. drought, Geophys. Res. Lett., 34, L20709, doi:10.1029/2007GL031541.
  • Groisman, P. Y., R. W.Knight, and T. R.Karl (2012), Changes in intense precipitation over the central United States, J. Hydrometeorol., 13, 4766, doi:
  • Heddinghaus, T. R., and P.Sabol (1991), A review of the Palmer Drought Severity Index and where do we go from here?, paper presented at Seventh Conference on Applied Climatology, Am. Meteorol. Soc., Boston, Mass., 10–13 Sept.
  • Helsel, D. R., and R. M.Hirsch (2002), Hydrologic analysis and interpretation, in Techniques of Water Resources Investigations Reports, chapter A3, pp. 266274, U.S. Geol. Surv., Reston, Va.
  • Hoerling, M. A. K., R.Dole, J. W.Nielsen-Gammon, J.Eischeid, J.Perlwitz, X. W.Quan, T.Zhang, P.Pegion, and M.Chen (2012), Anatomy of an extreme event, J. Clim., in press.
  • Karl, T. R., P. D.Jones, R. W.Knight, G.Kukla, N.Mummer, V.Razuvayev, K. P.Gallo, J.Lindseay, R. J.Charlson, and T. C.Peterson (1993), A new perspective on recent global warming: Asymmetric trends of daily maximum and minimum temperature, Bull. Am. Meteorol. Soc., 74(6), 10071023.
  • Karl, T. R., J. M.Melilo, and T. C.Peterson (Eds.) (2009), Global Climate Change Impacts in the United States, Cambridge Univ. Press, New York.
  • Kunkel, K. E., R. A.PielkeJr., and S. A.Changnon (1999), Temporal fluctuations in weather and climate extremes that cause economic and human health impacts: A review, Bull. Am. Meteorol. Soc., 80, 10771098, doi:<1077:TFIWAC>2.0.CO;2.
  • Menne, M. J., C. N.Williams, and R. S.Vose (2009), The United States Historical Climatology Network monthly temperature data– version 2, Bull. Am. Meteorol. Soc., 90, 9931107, doi:10.1175/2008BAMS2613.1.
  • Menne, M. J., C. N.WilliamsJr., and M. A.Palecki (2010), On the reliability of the U.S. surface temperature record, J. Geophys. Res., 115, D11108, doi:10.1029/2009JD013094.
  • Namias, J. (1983), Some causes of United States drought, J. Clim. Appl. Meteorol., 22, 2039.
  • Palmer, W. C. (1965), Meteorological drought, Res. Pap. 45., U.S. Weather Bur., NOAA Libr. and Inf. Serv. Div., Washington, D. C.
  • Peterson, T. C., et al. (2012), Monitoring and understanding changes in heat waves, cold waves, floods and droughts in the United States: State of Knowledge, Bull. Am. Meteorol. Soc., in press.
  • Schwartz, M. D., and T. R.Karl (1990), Spring phenology: Nature's experiment to detect the effect of “green-up” on surface MxTs, Mon. Weather Rev., 118(4), 883890, doi:10.1175/1520-0493(1990)118<0883:SPNETD>2.0.CO;2.
  • Schwartz, M. D., and B. E.Reiter (2000), Changes in North American spring, Int. J. Climatol., 20(8), 929932, doi:10.1002/1097-0088(20000630)20:8<929::AID-JOC557>3.0.CO;2-5.
  • Vose, R. S., S.Applequist, M. J.Menne, C. N.Williams, and P. W.Thorne (2012), An intercomparison of temperature trends in the U.S. Historical Climatology Network and recent atmospheric reanalyses, Geophys. Res. Lett., 39, L10703, doi:10.1029/2012GL051387.