Reply to comment on `Characterization of surface and ground water [delta]18O seasonal variation and its

HYDROLOGICAL PROCESSESHydrol. Process. 20, 3573–3578 (2006)Published online 4 September 2006 in Wiley InterScience(www.interscience.wiley.com) DOI: 10.1002/hyp.6516ReplytocommentReply to comment on ‘Characterization of surface and18ground water d O seasonal variation and its use forestimating groundwater residence times’ by R. E. CrissandW.E.Winston1 2 3 1Michael M. Reddy, * Paul Schuster, Carol Kendall and Micaela B. Reddy1 US Geological Survey, Water Resources Division, Denver Federal Center, MS 418, Lakewood, CO 80225, USA2 US Geological Survey, Water Resources Division, Boulder, CO 80303, USA3 US Water Resources Menlo Park, CA 94025, USAReceived 14 July 2006; Accepted 18 July 2006It is the nature of the scientific method to use a variety of models, procedures, techniques and data toquantify and analyse natural phenomena. Recently, in Reddy et al. (2006), we published a study in which18υ O values for precipitation, surface- and ground-water samples from the Shingobee River Headwaters Area(SRHA) were analysed using an amplitude-attenuation (convolution integral) approach for estimating meanresidence times (MRTs). This approach has been used in many small watershed studies (e.g. Stewart andMcDonnell, 1991; DeWalle et al., 1997; Burns and McDonnell, 1998; McGuire et al., 2002; Rodgers et al.,2005; McGuire and McDonnell, 2006). In a comment, Criss and Winston (2006) disagree with our method18and present an alternative approach for interpreting υ O ...