History and instrumentation
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This data package contains long-term hydrologic event data collected in the Tromble experimental watershed in the Jornada Basin of southern New Mexico, USA. This is a shrub-domindated catchment and historic vegetation maps indicate that this catchment was dominated by upland grasses in 1858, but by 1919ā20, these upland grasses had been replaced by creosotebush, tarbush, mesquite and mariola which still dominate. Grazing has not been excluded from this catchment, but low animal densities during the period investigated are likely to have had negligible effects. The dataset contains data from 2 multi-year periods of streamflow observations at this location: 1977-1985 and 2003-2011.
In 1977 John M. Tromble instrumented a 4.7 ha shrub-dominated catchment on the eastern bajada of the Jornada Experimental Range, New Mexico, USA. The catchment outlet was instrumented with a 2.8 m3 sā1 Santa Rita supercritical flume and flow depth in the flume was recorded using a paper chart recorder. Runoff data were collected from January 1977 until December 1985 at the catchment outlet. For this time period, rainfall data used in the subsequent analysis were collected at the Watershed rain gauge which was located 260 m from the catchment outlet. In 2003 the site was reactivated, and data collection was converted to a digital format. The paper chart was replaced with a Druck pressure transducer in the stilling well. A new rain gauge was installed at the catchment outlet and rainfall data from this gauge are included in the dataset for the period commencing 2003.
Data
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Four data files are available here, including event precipitation totals and sub-hourly runoff details for hydrologic events during the first and second observation periods. Variables included in the files for the first period (1977-1985) include event precipitation, stage heights at the flume, and calculated discharge rates. Variables included for the second period (2003-2011) include event precipitation, stage heights, calculated discharge rates, depth transducer millivolts, and rainfall intensity calculations.
Full details on methods and associated analyses are available in the publication by Turnbull et al. (2013).
Related data packages
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Runoff measurements since 2011 have been collected by the Vivoni group and are being prepared for publication at EDI.
References
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Turnbull, L., A. J. Parsons, J. Wainwright, and J. P. Anderson. \"Runoff responses to long-term rainfall variability in a shrub-dominated catchment.\" Journal of arid environments 91 (2013): 88-94.