> water resources investigations
> report 94-4076
US Department of the Interior
Spatial and Temporal Statistical Analysis of a Ground-Water Level Network, Broward County, Florida
Water-Resources Investigations Report 94-4076
The U.S. Geological Survey has developed a method to evaluate the spatial and temporal statistics of a continuous ground-water level recorder network in Broward County, Florida. Because the Broward County network is sparse for most spatial statistics, a technique has been developed to define polygons for each well that represent the area monitored by the well within specified criteria. The boundaries of these "confidence polygons" are defined by the endpoints of radial lines oriented toward the other wells. The lengths of these lines are determined as the statistically estimated distances to the points at which groundwater levels can be predicted within specified criteria. The confidence polygons indicate: (1) the areal coverage of the network, (2) locations where data are unavailable, and (3) areas of redundant data collection. Comparison with data from a non-continuous recorder well indicates that the confidence polygons are a good representation of areal coverages.
The temporal analysis utilizes statistical techniques similar to those used in the spatial method, defining variations in time rather than in space. Consequently, instead of defining radial distances to points, time intervals are defined over which water-level values can be predicted within a specified confidence. These "temporal confidence intervals" correspond to maximum allowable periods between field measurements.
To combine all results
from the analyses, a single coefficient reflecting the spatial and temporal
results has been developed. The coefficient referred to as the Spatial and
Temporal Adequacy and Redundancy Evaluation (STARE) and is determined by
three factors: the size of the confidence polygon, the number of times the
well is part of a redundant pair, and the temporal confidence interval.
This coefficient and the individual results of each analysis are used in
evaluating the present network and determining future management decisions.
(The entire report is available below.)
These reports and documents have been scanned from the original hard-copy materials and are made available on the internet in both HTML and PDF formats. Because these are scanned documents, we are unable to provide fully-accessible versions of these reports. If you cannot fully access the information in these documents, please contact Heather S. Henkel at firstname.lastname@example.org.
The HTML versions of these documents have been created to provide the information in a format that is quickly and easily readable over the Internet Selective pages and images can be printed from this HTML version by placing the cursor inside the right-hand frame and selecting the print option from the browser. The PDF version of the reports are also provided, and are the recommended format to use for the best printer format and resolution.
Please note - some PDF files are very large (over 2 MB) and may take some time to download, depending on your system.
View the HTML version of the report (downloads faster for on-line reading)
View the PDF version of this report (6.72MB) (best for printing)
U.S. Department of the Interior, U.S. Geological Survey
This page is: http://sofia.usgs.gov/publications/wri/94-4076/index.html
Comments and suggestions? Contact: Heather Henkel - Webmaster
Last updated: 04 September, 2013 @ 02:04 PM (KP)