Adam G. Johnson Stephen B. Gingerich 20170401 Vector Digital Data Set (Polygon) Reston, Virginia U.S. Geological Survey https://doi.org/10.5066/F7GM85H0 Stephen B. Gingerich Clifford I. Voss Adam G. Johnson 2017 Publication (Journal) Journal of Hydrology vol Philadelphia, Pennsylvania Elsevier http://doi.org/10.5066/F7736P3Q The zipped folder (Monthly_water_budget_Roi-Namur_2000-12.zip) associated with this metadata file contains 156 polygon shapefiles. Collectively, the 156 shapefiles contain spatially distributed estimates of groundwater recharge and other water-budget components, in inches, for Roi-Namur, Kwajalein Atoll, Republic of the Marshall Islands, for each month and year during 2000–12. The name of each shapefile indicates the year and month of the water-budget components contained in the shapefile. The month-year estimates of recharge and other water-budget components summarized in each shapefile were summed from daily water-budget components that were computed using a water-budget model. The equations of the water-budget model that we used for Roi-Namur were the same as those (equations 1–16) described in Johnson and others (2014). Johnson and others (2014), available at (https://pubs.usgs.gov/sir/2014/5168/) and hereinafter U.S. Geological Survey Scientific Investigations Report (USGS SIR) 2014-5168, describes a water-budget model used for the island of Maui, Hawaii. In USGS SIR 2014-5168, the “Conceptual Model” section has a general description of the water-budget model, and the “Model Calculations” section has a detailed description of the equations and variables used in the model. Several water-budget components considered in the Hawaii water-budget model described in USGS SIR 2014-5168 were excluded from the water-budget model for Roi-Namur. Fog interception and irrigation were excluded because they were assumed to be negligible. Water leakage from water-storage tanks was excluded because leakage rates were not known (Chugach Management Services, Inc., written communication, 2014). Water leakage from the rain water-catchment basins and water-transmission systems also was excluded. According to a soil database published by the U.S. Department of Agriculture, Natural Resources Conservation Service (2014), soils on islands of nearby atolls (Maloelap, Aur, Majuro, Arno, and Mili) have “very low to negligible runoff.” Although this soil database does not have soil information for islands of Kwajalein Atoll, we assumed soil properties for Roi-Namur were similar to those on islands of nearby atolls. Therefore, runoff to the ocean from all surfaces was excluded because it was assumed to be negligible owing to the island’s porous soil. Runoff from impervious surfaces, however, was quantified in the model as “excess water” that was assumed to either be captured by catchment systems for storage or flow to pervious surfaces. This abstract and the attribute definitions in this metadata file have descriptions of the input data we used in the model for Roi-Namur. Prior to computing recharge, we subdivided the island of Roi-Namur into 68 polygons, which we refer to as subareas, and which are represented in each shapefile. An explanation of the methods used to create the subareas is included in this metadata file in the description for the Subarea_ID attribute. The water-budget model computed daily groundwater recharge and other water-budget components separately for each of the 68 subareas. The attributes associated with each polygon include monthly estimates of rainfall, forest-canopy evaporation, rain water captured from the airport runway, surplus rainfall-catchment water discharged to the ground near the airport runway, potential evapotranspiration, actual evapotranspiration, total evapotranspiration, natural recharge from rainfall, artificial recharge from surplus rainfall-catchment water, and total recharge. For each attribute, this metadata file includes a description of how it was estimated in the water-budget model. The water-budget components in each shapefile were determined as part of an analysis to estimate the spatial and temporal distribution of groundwater recharge on Roi-Namur, for historic conditions (2000–12). The recharge estimates may be used in numerical groundwater models that can evaluate the effects of groundwater withdrawals seawater intrusion, and seawater flooding on groundwater levels, coastal discharge, and salinities in wells on Roi-Namur. The name of each shapefile indicates the month and year of the water-budget components contained in the shapefile: "Monthly_WB_components_inches_Roi_Namur_2000_01.shp" contains the water-budget components for January 2000. "Monthly_WB_components_inches_Roi_Namur_2000_02.shp" contains the water-budget components for February 2000. "Monthly_WB_components_inches_Roi_Namur_2000_03.shp" contains the water-budget components for March 2000. "Monthly_WB_components_inches_Roi_Namur_2000_04.shp" contains the water-budget components for April 2000. "Monthly_WB_components_inches_Roi_Namur_2000_05.shp" contains the water-budget components for May 2000. "Monthly_WB_components_inches_Roi_Namur_2000_06.shp" contains the water-budget components for June 2000. "Monthly_WB_components_inches_Roi_Namur_2000_07.shp" contains the water-budget components for July 2000. "Monthly_WB_components_inches_Roi_Namur_2000_08.shp" contains the water-budget components for August 2000. "Monthly_WB_components_inches_Roi_Namur_2000_09.shp" contains the water-budget components for September 2000. "Monthly_WB_components_inches_Roi_Namur_2000_10.shp" contains the water-budget components for October 2000. "Monthly_WB_components_inches_Roi_Namur_2000_11.shp" contains the water-budget components for November 2000. "Monthly_WB_components_inches_Roi_Namur_2000_12.shp" contains the water-budget components for December 2000. "Monthly_WB_components_inches_Roi_Namur_2001_01.shp" contains the water-budget components for January 2001. "Monthly_WB_components_inches_Roi_Namur_2001_02.shp" contains the water-budget components for February 2001. "Monthly_WB_components_inches_Roi_Namur_2001_03.shp" contains the water-budget components for March 2001. "Monthly_WB_components_inches_Roi_Namur_2001_04.shp" contains the water-budget components for April 2001. "Monthly_WB_components_inches_Roi_Namur_2001_05.shp" contains the water-budget components for May 2001. "Monthly_WB_components_inches_Roi_Namur_2001_06.shp" contains the water-budget components for June 2001. "Monthly_WB_components_inches_Roi_Namur_2001_07.shp" contains the water-budget components for July 2001. "Monthly_WB_components_inches_Roi_Namur_2001_08.shp" contains the water-budget components for August 2001. "Monthly_WB_components_inches_Roi_Namur_2001_09.shp" contains the water-budget components for September 2001. "Monthly_WB_components_inches_Roi_Namur_2001_10.shp" contains the water-budget components for October 2001. "Monthly_WB_components_inches_Roi_Namur_2001_11.shp" contains the water-budget components for November 2001. "Monthly_WB_components_inches_Roi_Namur_2001_12.shp" contains the water-budget components for December 2001. "Monthly_WB_components_inches_Roi_Namur_2002_01.shp" contains the water-budget components for January 2002. "Monthly_WB_components_inches_Roi_Namur_2002_02.shp" contains the water-budget components for February 2002. "Monthly_WB_components_inches_Roi_Namur_2002_03.shp" contains the water-budget components for March 2002. "Monthly_WB_components_inches_Roi_Namur_2002_04.shp" contains the water-budget components for April 2002. "Monthly_WB_components_inches_Roi_Namur_2002_05.shp" contains the water-budget components for May 2002. "Monthly_WB_components_inches_Roi_Namur_2002_06.shp" contains the water-budget components for June 2002. "Monthly_WB_components_inches_Roi_Namur_2002_07.shp" contains the water-budget components for July 2002. "Monthly_WB_components_inches_Roi_Namur_2002_08.shp" contains the water-budget components for August 2002. "Monthly_WB_components_inches_Roi_Namur_2002_09.shp" contains the water-budget components for September 2002. "Monthly_WB_components_inches_Roi_Namur_2002_10.shp" contains the water-budget components for October 2002. "Monthly_WB_components_inches_Roi_Namur_2002_11.shp" contains the water-budget components for November 2002. "Monthly_WB_components_inches_Roi_Namur_2002_12.shp" contains the water-budget components for December 2002. "Monthly_WB_components_inches_Roi_Namur_2003_01.shp" contains the water-budget components for January 2003. "Monthly_WB_components_inches_Roi_Namur_2003_02.shp" contains the water-budget components for February 2003. "Monthly_WB_components_inches_Roi_Namur_2003_03.shp" contains the water-budget components for March 2003. "Monthly_WB_components_inches_Roi_Namur_2003_04.shp" contains the water-budget components for April 2003. "Monthly_WB_components_inches_Roi_Namur_2003_05.shp" contains the water-budget components for May 2003. "Monthly_WB_components_inches_Roi_Namur_2003_06.shp" contains the water-budget components for June 2003. "Monthly_WB_components_inches_Roi_Namur_2003_07.shp" contains the water-budget components for July 2003. "Monthly_WB_components_inches_Roi_Namur_2003_08.shp" contains the water-budget components for August 2003. "Monthly_WB_components_inches_Roi_Namur_2003_09.shp" contains the water-budget components for September 2003. "Monthly_WB_components_inches_Roi_Namur_2003_10.shp" contains the water-budget components for October 2003. "Monthly_WB_components_inches_Roi_Namur_2003_11.shp" contains the water-budget components for November 2003. "Monthly_WB_components_inches_Roi_Namur_2003_12.shp" contains the water-budget components for December 2003. "Monthly_WB_components_inches_Roi_Namur_2004_01.shp" contains the water-budget components for January 2004. "Monthly_WB_components_inches_Roi_Namur_2004_02.shp" contains the water-budget components for February 2004. "Monthly_WB_components_inches_Roi_Namur_2004_03.shp" contains the water-budget components for March 2004. "Monthly_WB_components_inches_Roi_Namur_2004_04.shp" contains the water-budget components for April 2004. "Monthly_WB_components_inches_Roi_Namur_2004_05.shp" contains the water-budget components for May 2004. "Monthly_WB_components_inches_Roi_Namur_2004_06.shp" contains the water-budget components for June 2004. "Monthly_WB_components_inches_Roi_Namur_2004_07.shp" contains the water-budget components for July 2004. "Monthly_WB_components_inches_Roi_Namur_2004_08.shp" contains the water-budget components for August 2004. "Monthly_WB_components_inches_Roi_Namur_2004_09.shp" contains the water-budget components for September 2004. "Monthly_WB_components_inches_Roi_Namur_2004_10.shp" contains the water-budget components for October 2004. "Monthly_WB_components_inches_Roi_Namur_2004_11.shp" contains the water-budget components for November 2004. "Monthly_WB_components_inches_Roi_Namur_2004_12.shp" contains the water-budget components for December 2004. "Monthly_WB_components_inches_Roi_Namur_2005_01.shp" contains the water-budget components for January 2005. "Monthly_WB_components_inches_Roi_Namur_2005_02.shp" contains the water-budget components for February 2005. "Monthly_WB_components_inches_Roi_Namur_2005_03.shp" contains the water-budget components for March 2005. "Monthly_WB_components_inches_Roi_Namur_2005_04.shp" contains the water-budget components for April 2005. "Monthly_WB_components_inches_Roi_Namur_2005_05.shp" contains the water-budget components for May 2005. "Monthly_WB_components_inches_Roi_Namur_2005_06.shp" contains the water-budget components for June 2005. "Monthly_WB_components_inches_Roi_Namur_2005_07.shp" contains the water-budget components for July 2005. "Monthly_WB_components_inches_Roi_Namur_2005_08.shp" contains the water-budget components for August 2005. "Monthly_WB_components_inches_Roi_Namur_2005_09.shp" contains the water-budget components for September 2005. "Monthly_WB_components_inches_Roi_Namur_2005_10.shp" contains the water-budget components for October 2005. "Monthly_WB_components_inches_Roi_Namur_2005_11.shp" contains the water-budget components for November 2005. "Monthly_WB_components_inches_Roi_Namur_2005_12.shp" contains the water-budget components for December 2005. "Monthly_WB_components_inches_Roi_Namur_2006_01.shp" contains the water-budget components for January 2006. "Monthly_WB_components_inches_Roi_Namur_2006_02.shp" contains the water-budget components for February 2006. "Monthly_WB_components_inches_Roi_Namur_2006_03.shp" contains the water-budget components for March 2006. "Monthly_WB_components_inches_Roi_Namur_2006_04.shp" contains the water-budget components for April 2006. "Monthly_WB_components_inches_Roi_Namur_2006_05.shp" contains the water-budget components for May 2006. "Monthly_WB_components_inches_Roi_Namur_2006_06.shp" contains the water-budget components for June 2006. "Monthly_WB_components_inches_Roi_Namur_2006_07.shp" contains the water-budget components for July 2006. "Monthly_WB_components_inches_Roi_Namur_2006_08.shp" contains the water-budget components for August 2006. "Monthly_WB_components_inches_Roi_Namur_2006_09.shp" contains the water-budget components for September 2006. "Monthly_WB_components_inches_Roi_Namur_2006_10.shp" contains the water-budget components for October 2006. "Monthly_WB_components_inches_Roi_Namur_2006_11.shp" contains the water-budget components for November 2006. "Monthly_WB_components_inches_Roi_Namur_2006_12.shp" contains the water-budget components for December 2006. "Monthly_WB_components_inches_Roi_Namur_2007_01.shp" contains the water-budget components for January 2007. "Monthly_WB_components_inches_Roi_Namur_2007_02.shp" contains the water-budget components for February 2007. "Monthly_WB_components_inches_Roi_Namur_2007_03.shp" contains the water-budget components for March 2007. "Monthly_WB_components_inches_Roi_Namur_2007_04.shp" contains the water-budget components for April 2007. "Monthly_WB_components_inches_Roi_Namur_2007_05.shp" contains the water-budget components for May 2007. "Monthly_WB_components_inches_Roi_Namur_2007_06.shp" contains the water-budget components for June 2007. "Monthly_WB_components_inches_Roi_Namur_2007_07.shp" contains the water-budget components for July 2007. "Monthly_WB_components_inches_Roi_Namur_2007_08.shp" contains the water-budget components for August 2007. "Monthly_WB_components_inches_Roi_Namur_2007_09.shp" contains the water-budget components for September 2007. "Monthly_WB_components_inches_Roi_Namur_2007_10.shp" contains the water-budget components for October 2007. "Monthly_WB_components_inches_Roi_Namur_2007_11.shp" contains the water-budget components for November 2007. "Monthly_WB_components_inches_Roi_Namur_2007_12.shp" contains the water-budget components for December 2007. "Monthly_WB_components_inches_Roi_Namur_2008_01.shp" contains the water-budget components for January 2008. "Monthly_WB_components_inches_Roi_Namur_2008_02.shp" contains the water-budget components for February 2008. "Monthly_WB_components_inches_Roi_Namur_2008_03.shp" contains the water-budget components for March 2008. "Monthly_WB_components_inches_Roi_Namur_2008_04.shp" contains the water-budget components for April 2008. "Monthly_WB_components_inches_Roi_Namur_2008_05.shp" contains the water-budget components for May 2008. "Monthly_WB_components_inches_Roi_Namur_2008_06.shp" contains the water-budget components for June 2008. "Monthly_WB_components_inches_Roi_Namur_2008_07.shp" contains the water-budget components for July 2008. "Monthly_WB_components_inches_Roi_Namur_2008_08.shp" contains the water-budget components for August 2008. "Monthly_WB_components_inches_Roi_Namur_2008_09.shp" contains the water-budget components for September 2008. "Monthly_WB_components_inches_Roi_Namur_2008_10.shp" contains the water-budget components for October 2008. "Monthly_WB_components_inches_Roi_Namur_2008_11.shp" contains the water-budget components for November 2008. "Monthly_WB_components_inches_Roi_Namur_2008_12.shp" contains the water-budget components for December 2008. "Monthly_WB_components_inches_Roi_Namur_2009_01.shp" contains the water-budget components for January 2009. "Monthly_WB_components_inches_Roi_Namur_2009_02.shp" contains the water-budget components for February 2009. "Monthly_WB_components_inches_Roi_Namur_2009_03.shp" contains the water-budget components for March 2009. "Monthly_WB_components_inches_Roi_Namur_2009_04.shp" contains the water-budget components for April 2009. "Monthly_WB_components_inches_Roi_Namur_2009_05.shp" contains the water-budget components for May 2009. "Monthly_WB_components_inches_Roi_Namur_2009_06.shp" contains the water-budget components for June 2009. "Monthly_WB_components_inches_Roi_Namur_2009_07.shp" contains the water-budget components for July 2009. "Monthly_WB_components_inches_Roi_Namur_2009_08.shp" contains the water-budget components for August 2009. "Monthly_WB_components_inches_Roi_Namur_2009_09.shp" contains the water-budget components for September 2009. "Monthly_WB_components_inches_Roi_Namur_2009_10.shp" contains the water-budget components for October 2009. "Monthly_WB_components_inches_Roi_Namur_2009_11.shp" contains the water-budget components for November 2009. "Monthly_WB_components_inches_Roi_Namur_2009_12.shp" contains the water-budget components for December 2009. "Monthly_WB_components_inches_Roi_Namur_2010_01.shp" contains the water-budget components for January 2010. "Monthly_WB_components_inches_Roi_Namur_2010_02.shp" contains the water-budget components for February 2010. "Monthly_WB_components_inches_Roi_Namur_2010_03.shp" contains the water-budget components for March 2010. "Monthly_WB_components_inches_Roi_Namur_2010_04.shp" contains the water-budget components for April 2010. "Monthly_WB_components_inches_Roi_Namur_2010_05.shp" contains the water-budget components for May 2010. "Monthly_WB_components_inches_Roi_Namur_2010_06.shp" contains the water-budget components for June 2010. "Monthly_WB_components_inches_Roi_Namur_2010_07.shp" contains the water-budget components for July 2010. "Monthly_WB_components_inches_Roi_Namur_2010_08.shp" contains the water-budget components for August 2010. "Monthly_WB_components_inches_Roi_Namur_2010_09.shp" contains the water-budget components for September 2010. "Monthly_WB_components_inches_Roi_Namur_2010_10.shp" contains the water-budget components for October 2010. "Monthly_WB_components_inches_Roi_Namur_2010_11.shp" contains the water-budget components for November 2010. "Monthly_WB_components_inches_Roi_Namur_2010_12.shp" contains the water-budget components for December 2010. "Monthly_WB_components_inches_Roi_Namur_2011_01.shp" contains the water-budget components for January 2011. "Monthly_WB_components_inches_Roi_Namur_2011_02.shp" contains the water-budget components for February 2011. "Monthly_WB_components_inches_Roi_Namur_2011_03.shp" contains the water-budget components for March 2011. "Monthly_WB_components_inches_Roi_Namur_2011_04.shp" contains the water-budget components for April 2011. "Monthly_WB_components_inches_Roi_Namur_2011_05.shp" contains the water-budget components for May 2011. "Monthly_WB_components_inches_Roi_Namur_2011_06.shp" contains the water-budget components for June 2011. "Monthly_WB_components_inches_Roi_Namur_2011_07.shp" contains the water-budget components for July 2011. "Monthly_WB_components_inches_Roi_Namur_2011_08.shp" contains the water-budget components for August 2011. "Monthly_WB_components_inches_Roi_Namur_2011_09.shp" contains the water-budget components for September 2011. "Monthly_WB_components_inches_Roi_Namur_2011_10.shp" contains the water-budget components for October 2011. "Monthly_WB_components_inches_Roi_Namur_2011_11.shp" contains the water-budget components for November 2011. "Monthly_WB_components_inches_Roi_Namur_2011_12.shp" contains the water-budget components for December 2011. "Monthly_WB_components_inches_Roi_Namur_2012_01.shp" contains the water-budget components for January 2012. "Monthly_WB_components_inches_Roi_Namur_2012_02.shp" contains the water-budget components for February 2012. "Monthly_WB_components_inches_Roi_Namur_2012_03.shp" contains the water-budget components for March 2012. "Monthly_WB_components_inches_Roi_Namur_2012_04.shp" contains the water-budget components for April 2012. "Monthly_WB_components_inches_Roi_Namur_2012_05.shp" contains the water-budget components for May 2012. "Monthly_WB_components_inches_Roi_Namur_2012_06.shp" contains the water-budget components for June 2012. "Monthly_WB_components_inches_Roi_Namur_2012_07.shp" contains the water-budget components for July 2012. "Monthly_WB_components_inches_Roi_Namur_2012_08.shp" contains the water-budget components for August 2012. "Monthly_WB_components_inches_Roi_Namur_2012_09.shp" contains the water-budget components for September 2012. "Monthly_WB_components_inches_Roi_Namur_2012_10.shp" contains the water-budget components for October 2012. "Monthly_WB_components_inches_Roi_Namur_2012_11.shp" contains the water-budget components for November 2012. "Monthly_WB_components_inches_Roi_Namur_2012_12.shp" contains the water-budget components for December 2012. 20000101 20121231 2017 Complete None planned 167.464568677 167.486070937 9.402748725 9.389293494 USGS Thesaurus precipitation (atmospheric) evaporation transpiration water budget recharge inlandWaters ISO 19115 Topic Category geoscientificInformation inlandWaters environment USGS Metadata Identifier USGS:d86b6ac9-c28e-43ea-a854-9d573b1b781d Geographic Names Information System Marshall Islands Kwajalein Roi-Namur None. Please see 'Distribution Info' for details. None. Users are advised to read the data set's metadata thoroughly to understand appropriate use and data limitations. U.S. Geological Survey, Pacific Islands Water Science Center Adam G Johnson Hydrologist mailing address

Pacific Islands Water Science Center, 1845 Wasp Boulevard, Bld 176

Honolulu HI 96818 US 808-690-9583 808-690-9599 ajohnson@usgs.gov https://water.usgs.gov/GIS/browse/RN_recharge_graphic.png Image of the png Environment as of Metadata Creation: Microsoft Windows 7 Version 6.1 (Build 7601) Service Pack 1; Esri ArcGIS 10.4.1 (Build 5686) Service Pack N/A (Build N/A) No formal attribute accuracy tests were conducted. Numerical values for the water-budget components were computed using the water-budget model described in U.S. Geological Survey Scientific Investigations Report 2014-5168. No spatial overlaps were found in the shapefile associated with this metadata file. Numerical values are within expected ranges. Data set is considered complete for the information presented, as described in the abstract. Users are advised to read the rest of the metadata record carefully for additional details. A formal accuracy assessment of the horizontal positional information in the data set has not been conducted. The horizontal accuracy of the polygons of this data set is a function of the horizontal accuracies of all other data sets used to create this data set. The horizontal accuracy of each of the other data sets, however, typically was not quantified. Therefore, the horizontal accuracy of this dataset cannot be quantified. A formal accuracy assessment of the vertical positional information in the data set is not applicable. Liu, Z. and Fischer, L. 20100101 Vector Digital Data Set McClellan, California, U.S. U.S. Department of Agriculture, Forest Service, Pacific Southwest Region, State and Private Forestry, Remote Sensing Laboratory https://www.fs.usda.gov/detailfull/r5/forest-grasslandhealth/?cid=fsbdev3_046690&width=full Digital and/or Hardcopy Resources 20080101 20100101 publication date Land cover Source information used in support of the development of the data set. U.S. Geological Survey 20100101 Vector Digital Data Set Sioux Falls, SD Wildland Fire Science, Earth Resources Observation and Science Center, U.S. Geological Survey http://landfire.cr.usgs.gov/viewer/ Digital and/or Hardcopy Resources 20080101 20081231 publication date Forest-canopy cover Source information used in support of the development of the data set. Allen, R.G., Pereira, L.S., Raes, Dirk, and Smith, Martin 19980101 Other Rome Food and Agriculture Organization of the United Nations http://www.fao.org/docrep/X0490E/X0490E00.htm Digital and/or Hardcopy Resources 19980101 publication date Evapotranspiration Source information used in support of estimating evapotranspiration Johnson, A.G., Engott, J.A., and Bassiouni, Maoya 20141126 Scientific Investigations Report (SIR) 2014–5168 Reston, Virginia U.S. Geological Survey Scientific Investigations Report 2014–5168 http://doi.org/10.3133/sir20145168 Digital and/or Hardcopy Resources 19780101 20071231 publication date Water-budget model Source information contained equations for the water-budget model calculations. U.S. Department of Agriculture, Natural Resources Conservation Service 20140101 Vector Digital Data Set Fort Worth, Texas U.S. Department of Agriculture, Natural Resources Conservation Service http://datagateway.nrcs.usda.gov/GDGOrder.aspx?order=QuickState. Digital and/or Hardcopy Resources 20140101 publication date Soils Source information used in support of estimating soil properties. Wolff, D. B., Marks, D. A., Amitai, E., Silberstein, D. S., Fisher, B. L., Tokay, A., Wang, J., and Pippitt, J. L. 20050401 Publication (Journal Article) American Meteorological Society Journal of Atmospheric and Oceanic Technology http://doi.org/10.1175/JTECH1700.1 Digital and/or Hardcopy Resources 20000101 20121231 publication date Rainfall Source information provided daily rainfall values used in water-budget model. U.S. Department of Agriculture, Natural Resources Conservation Service 20070817 Raster Digital Data (Aerial Imagery) Forth Worth, Texas U.S. Department of Agriculture, Natural Resources Conservation Service https://gdg.sc.egov.usda.gov/GDGOrder.aspx Digital and/or Hardcopy Resources 20040125 20060528 publication date Land cover Source information used in support to delineate impervious areas. The spatial extents of the subareas in this shapefile were created in ArcMap by intersecting spatial datasets of land cover, forest-canopy cover, and impervious areas. Refer to the definition of "Subarea_ID" attribute in this metadata file for further information. 20141230 Vector G-polygon 68 Universal Transverse Mercator 58 0.9996 165.0 0.0 500000.0 0.0 coordinate pair 0.6096 0.6096 Meter D_WGS_1984 WGS_1984 6378137.0 298.257223563 Monthly_WB_components_inches_Roi_Namur_2000_01 thru 2012_12 Table containing attribute information associated with the data set. Producer defined Subarea_ID Identification number of the model subarea. The model domain was subdivided into 68 polygons, termed subareas, mainly using spatial variations in land cover and forest-canopy cover. The spatial extents of the subareas were considered temporally constant during the historical simulation period from 2000 to 2012. Land cover was classified as either barren, forest, or urban using the land-cover map of Liu and Fischer (2010). Areas classified as water by Liu and Fischer (2010) were excluded from the water-budget model domain. All parts of the island with barren land cover were grouped into one subarea and assigned a Subarea_ID value of 1. Parts of the island with forest land cover were subdivided into nine subareas (Subarea_ID values: 57, 58, 59, 60, 61, 62, 63, 64, and 65) on the basis of nine canopy-cover values (15, 25, 35, 45, 55, 65, 75, 85, and 95 percent, respectively) defined in a map of forest-canopy cover (U.S. Geological Survey, 2010). The remaining parts of the island were subdivided into 58 subareas with urban land cover. Rain water catchment basins and the part of the airport runway from which rain water was captured and retained, hereinafter referred to as “catchment water”, was assigned a Subarea_ID value of 2 (see description for R_Capture attribute). An oval-shaped area assumed to have artificial recharge from surplus catchment water discharged to the ground was considered one subarea (Subarea_ID 68) in the model; this subarea represents a swale above a horizontal skimming well near the airport runway. The spatial extent Subarea_ID 68 was defined in a manner that would allow us to approximate the spatial dispersion of artificial recharge from surplus catchment water from the base of the root zone to the groundwater table. The part of the island consisting of impervious surfaces and pervious land within 20 feet of the impervious surfaces was subdivided into 55 subareas. We defined subareas in this manner for the model to account for “excess water”, the portion of rainfall that fell onto impervious surfaces and ultimately flowed onto adjacent pervious surfaces. Specifically, the spatial extents of these 55 subareas were delineated using the ArcGIS Buffer tool, and with the following Buffer-tool options: (1) “Input Features” were shapefiles of impervious surfaces only, (2) “Linear unit” was 20 feet, (3) “Side Type” was FULL, (4) “End Type” was ROUND, (5) “Method” was PLANAR, and (6) “Dissolve Type” was ALL. The output of the ArcGIS buffer tool process was a shapefile consisting of one multipart polygon, whose spatial extent consisted of impervious surfaces and pervious surfaces within 20 feet of impervious surfaces. Next, the multipart polygon was separated into 55 polygons (subareas for the model) in ArcMap using manual edits and the “Explode Multipart Feature” tool in the Advanced Editing options of ArcMap. Impervious surfaces, mainly consisting of buildings and pavement, were identified in orthoimagery (U.S. Department of Agriculture, Natural Resources Conservation Service, 2007) or were delineated on the basis of visits to the island by one of the authors in 2014. All remaining parts of the island had urban land cover and were grouped into one subarea and assigned a Subarea_ID value of 56. Producer defined 1 68 Area_sq_m Area of subarea, in square meters Producer defined 359.064 733783.791 Land_Cover Land-cover name. Liu and Fischer (2010) Barren Land cover is barren. Producer defined Forest Land cover is forest. Producer defined Urban Land cover is urban. Producer defined ImpervFrac The fraction of the subarea estimated to be covered by impervious surfaces, such as paved roads and buildings. The impervious fraction of each subarea was estimated using the extents of impervious surfaces that were (1) identified in orthoimagery (U.S. Department of Agriculture, Natural Resources Conservation Service, 2007) or (2) mapped during field work in 2014 and later delineated in a GIS. In the model calculations, the impervious fraction was used to separate, from the total rain that fell on a subarea, a depth of water that was treated computationally as though it fell on an impervious surface. The attribute definition for R_Capture includes a description of how ImpervFrac is used to compute the amount of rain water that flows to pervious surface or is captured by the rainfall-catchment system. Producer defined 0 0.99 Fraction of 1 Year Year Producer defined 2000 2012 Month Month Producer defined 1 12 Rain Monthly rainfall, in inches. Monthly rainfall was summed from daily rainfall. Daily rainfall measurements from 17 rain gages that had available data were used to reconstruct the record of observed daily rainfall on Roi-Namur during 2000–12 for the water-budget model. The rainfall record for one of the rain gages was provided by Stan Jazwinski (Chugach Management Services, Inc., written communication, 2014). Rainfall records for the remaining rain gages, which were used to validate satellite-based rainfall estimates of the Tropical Rainfall Measuring Mission (Wolff and others, 2005), were obtained from http://trmm-fc.gsfc.nasa.gov/trmm_gv/gauge/index.html. Sixteen of the 17 rain gages were located on Roi-Namur. One rain gage, located on Gagan island about eight miles south-southeast of Roi-Namur, was used only to estimate daily rainfall in the model during January 1–April 19, 2000 when rainfall data were not available for any rain gages on Roi-Namur. The median of daily rainfall measurements for the rain gages on Roi-Namur was rounded to the nearest 0.01 inches and then was used in the model for days when more than one rain gage had rainfall data. Although none of the 17 rain gages had complete records for 2000–12, existing records combined provided rainfall data for 99.8 percent of the days during 2000-12, with data available from at least one rain gage on each of those days. Daily rainfall was assumed to be negligible on 10 (or 0.2 percent) of the days during 2000–12 when daily rainfall measurements were unavailable. December 2002 had six days with no rainfall measurements; January 2000 and 2002 each had two days with no rainfall measurements. Producer defined 0.24 20.36 Inches Cnpy_Evap Monthly forest-canopy evaporation, in inches. Monthly forest-canopy evaporation was summed from daily forest-canopy evaporation estimates. Subareas with barren and urban land cover were assigned Cnpy_Evap values of zero because the water-budget model computed canopy evaporation only for subareas with forest land cover. For subareas with forest land cover, daily forest-canopy evaporation was computed in the model on the basis of the following six parameters: daily rainfall, canopy cover, canopy capacity, stemflow (as a percentage of rainfall), trunk-storage capacity, and the ratio of mean evaporation rate to rainfall rate during saturated conditions (hereinafter “V”). All of these parameters except daily rainfall were assumed to be temporally constant. All of these parameters except canopy cover were assumed to be spatially uniform. A map of forest-canopy cover (U.S. Geological Survey, 2010) was used to estimate canopy-cover values of subareas with forest land cover. Canopy-cover values varied spatially between 0.15 and 0.95, which imply between 15 and 95 percent forest-canopy cover among forested subareas of Roi-Namur. Values assigned to canopy capacity (0.05 inch), stemflow (4 percent of rainfall), and trunk-storage capacity (0.01 inch) were the same as those used to estimate canopy evaporation in the water-budget model for Maui, Hawaii, as described in USGS SIR 2014-5168. The parameter V was estimated using hourly rainfall data and hourly reference grass evapotranspiration (ET) estimates for Kwajalein Island because such data and estimates were not available for Roi-Namur. Hourly rainfall data were obtained from http://trmm-fc.gsfc.nasa.gov/trmm_gv/gauge/index.html for two rain gages (named KWA0221 and KWA2201 in the source dataset) on Kwajalein Island. An estimated value of V was developed for use in our water-budget model for Roi-Namur. First, we computed daily reference grass ET (hereinafter reference ET) using the method outlined in Allen and others (1998) and available meteorological data. Weather-station data and downwelling total solar-irradiance measurements (herein solar radiation) were obtained from www.ncdc.nooa.gov and http://www.esrl.noaa.gov/gmd/dv/data/index.php?site=kwj, respectively. Next, we estimated hourly reference ET by assuming it varied diurnally in proportion to solar radiation. Hourly reference ET was computed as the product of daily reference ET and an hourly solar factor where each hourly solar factor was equal to the ratio of hourly-to-daily solar radiation. Next, we computed values of V as the quotient of hourly reference ET and hourly rainfall for each hour when rainfall exceeded the canopy capacity (0.05 inches). Finally, we used the average (0.03) of all 5,421 computed hourly V values for 2000–12 in our water-budget calculations for Roi-Namur. Producer defined 0 1.995 Inches R_Capture Monthly rain water, in inches, that was captured from part of the runway for storage. This “rain-capture” component represents model estimates of rain water that fell on impervious surfaces on part of the airport runway and adjacent catchment basins and then was subsequently captured and stored. In the water-budget model, this component was limited to one subarea (Subarea_ID 2) that represents the part of the runway and catchment basins from which rain water was assumed to be captured. In the water-budget model, the rainfall retention-capacity of all impervious surfaces in the model area was assumed to be 0.25 inches, meaning that up to 0.25 inches of rain could be stored on an impervious surface, where it could evaporate or be stored until the following day. The remaining rain water, that in excess of 0.25 inches, was considered “excess water.” For one subarea (Subarea_ID 2), the excess water was assumed to be captured by a rainfall-catchment system. Daily amounts of excess water captured from this particular subarea were summed into monthly amounts that were reported in each shapefile as R_Capture. For each of the remaining subareas with an impervious-fraction value greater than 0, the model added excess water from the impervious surface to the plant-root zone of the pervious “buffer” area adjacent to and within 20 ft of the impervious surface. Producer defined 0 15.683 Inches SC_water Monthly surplus catchment water discharged to the ground, in inches. Beginning in 2009, personnel on Roi-Namur began to periodically discharge surplus catchment water to the ground as a means to recharge the island’s freshwater lens. On Roi-Namur, surplus catchment water was discharged to the ground from equipment at a few vertical wells distributed in an oval-shaped swale, represented by the subarea with Subarea_ID 68, above a horizontal skimming well adjacent to the airport runway. The surplus catchment water was a portion of the rain that fell on and was captured from part the airport runway and catchment basins adjacent to the runway (see description for R_Capture). A record of the volumes of catchment water that were discharged to the ground each day between 2009 and 2012 was provided by Stan Jazwinski, (Chugach Management Services, Inc., written communication, 2014). Daily volumes of surplus-catchment water were summed into monthly volumes, which were reported in this file as a uniform depth of water for the total area of one subarea (Subarea_ID 68). Refer to descriptions of the Actual_ET and Artfl_Rech attributes in this metadata file for explanations of the methods used to estimate evapotranspiration and artificial recharge from surplus catchment water discharged to the ground. Producer defined 0 34.794 Inches P_ET Monthly potential evapotranspiration, in inches. The rate of potential evapotranspiration (potential ET), which represents the maximum ET rate from the plant-root zone, is needed to compute the actual ET rate in the water-budget model. Potential ET for each subarea was estimated as the product of a crop coefficient and reference ET. Crop coefficients were assigned to each subarea according to land cover and were assumed to be temporally constant. The crop coefficient assigned to barren land cover, 1.18, was the average of the range of values suggested by Allen and others (1998) for bare soil. The crop coefficient assigned to urban land cover, 1.18, was the same as that used for developed land covers in a water-budget model for the island of Maui, Hawaii (see USGS SIR 2014-5168). The crop coefficient assigned to forest land cover, 0.69, also was used to compute actual ET for scrub forest and limestone forest land covers in a water-budget model for Guam [see Johnson (2012), a USGS SIR (2012-5028)]. The crop coefficients assigned to the barren and urban land-cover classes integrated the effects of transpiration and ground evaporation. The crop coefficients assigned to the forest land-cover class integrated the effects of transpiration and ground evaporation only, because canopy evaporation was accounted for separately (see fig.5 in USGS SIR 2014-5168). Reference ET, as defined for our analysis, is the ET rate of a hypothetical grass surface completely shading the ground, of uniform height, and optimum soil-water conditions for given climatic conditions. For input to the water-budget model, we created a record of monthly reference-ET values for 2000–12, and we assumed that reference ET was spatially uniform across Roi-Namur. Because climate data needed to compute reference ET for Roi-Namur during 2000–12 were not available, we developed a linear regression using rainfall and other climate data from Kwajalein Island only. We developed the linear regression for the purpose of estimating monthly reference ET for Roi-Namur on the basis of daily rainfall records, the only multi-year ground-based climate dataset that was available for Roi-Namur (see definition for “Rain” attribute). To develop the linear regression, we first computed daily reference ET for Kwajalein Island according to the method described in Allen and others (1998) and by using values of (1) solar radiation obtained from NOAA Earth System Research Laboratory, Global Monitoring Division (http://www.esrl.noaa.gov/gmd/dv/data/index.php?site=kwj), and (2) average daily dew-point temperature, wind speed, and minimum and maximum daily air temperature obtained from National Climatic Data Center’s (http://www.ncdc.noaa.gov/) “global surface summary of the day” dataset for station number 913660. Next, we summed the daily reference-ET estimates for Kwajalein Island into monthly values. Next, we used the monthly reference-ET values and daily rainfall values (also obtained from http://www.ncdc.noaa.gov/) for Kwajalein Island during 1992–2009 to develop the following linear regression, hereinafter equation 1: RefET = 0.215 – 0.139 * RD, where RefET is monthly reference ET, expressed as a percentage difference from mean monthly reference ET during 1992–2009, and RD is the number of rain days per month, expressed as a percentage difference from mean monthly number of rainy days per month during 1992–2009. For example, according to equation 1, if the number of rain days for a given month was 20 percent less than the mean number of rain days for that month (RD = -20), then monthly RefET would be 3 percent greater than mean monthly reference ET for the month. The period 1992–2009 was selected on the basis of data availability. For our analysis, only days with rainfall amounts of at least 0.01 inches were considered rain days, and all remaining days were considered dry days. The regression’s coefficient of determination, 0.187, was low, but its slope was significant (p-value was less than 0.0001). The intercept of equation 1 was not significant (p-value was 0.583). Given the dearth of available climate data for Roi-Namur, however, equation 1 was considered adequate for our analysis and was used to estimate monthly reference-ET values for Roi-Namur during 2000–12 as follows. First, an RD value was computed, for each month during 2000–12, as 100 percent times the quotient of (1) the number of rain days on Roi-Namur for the month minus the mean number of rain days on Kwajalein Island for the corresponding month during 1992–2009, and (2) the mean number of rain days on Kwajalein Island for the corresponding month during 1992–2009. Next, the RD values were applied in equation 1 to compute RefET values for each month during 2000–12. Last, each monthly reference ET value for Roi-Namur during 2000–12 was computed as the sum of (1) mean monthly reference ET for Kwajalein Island during 1992–2009 and (2) RefET divided by 100 percent times mean monthly reference ET for Kwajalein during 1992–2009. The resulting estimates of monthly reference ET for Roi-Namur during 2000–12, ranged from 0.17 to 0.25 inches per day and were used in the water-budget calculations. The monthly reference ET values we estimated for Roi-Namur using equation 1 were within 8 percent of the values that we estimated for Kwajalein Island using climate data. In the water-budget model for Roi-Namur, rates of daily reference ET were assumed to be uniform over each day in a given month, such that the rates for each day of a given month added up to the monthly rate. Producer defined 3.642 8.956 Inches Actual_ET Monthly actual evapotranspiration, in inches. Monthly actual evapotranspiration (ET) was summed from daily actual ET values. For subareas with barren and urban land covers, actual ET computed by the water-budget model implicitly represents the sum of transpiration and ground evaporation. For subareas with forest land cover, actual ET computed by the water-budget model implicitly represents the sum of transpiration and ground evaporation only because canopy evaporation was computed separately (refer to USGS 2014-5168 for further explanation). Actual ET for each subarea was computed using equations 10 through 14 in USGS SIR 2014-5168. Collectively, these equations require potential ET, which is computed by the water-budget model (see P_ET), and three model-input parameters for the plant-root zone: depletion fraction, root depth, and available water capacity. Potential ET, depletion fraction, and root depth varied spatially according to land cover, whereas depletion fraction was assumed to be spatially uniform. Potential ET varied temporally, whereas depletion fraction, root depth, and available water capacity were assumed to be temporally constant. Subareas with barren and urban land covers were assigned a depletion fraction of 0.5, the same as that used in USGS SIR 2014-5168. Subareas with forest land cover were assigned a depletion fraction of 1.0 because tree roots were assumed to extend into saturated groundwater. Subareas with forest land cover were assigned a root depth of 60 inches. The root depths assigned to subareas with urban land cover, 12 inches, and with barren land cover, 5 inches, were the same as those used in water-budget models for Guam (see USGS SIR 2012-5028) and Maui (see USGS SIR 2014-5168). Estimates of available water capacity of soils for Kwajalein Island and for islands of nearby atolls were used in the water budget because such estimates for soils on Roi-Namur were not found. An available water capacity value of 5 percent, or 0.05 inches of plant-available water per inch of soil depth, was considered by Hunt and Peterson (1980) to be representative of soils on Kwajalein Island. The Natural Resources Conservation Service (2014) soil database did not include the islands of Kwajalein Atoll, but did include the islands of nearby atolls (Maloelap, Aur, Majuro, Arno, and Mili). Based on this soil database, the available water capacity of soils on the islands of these nearby atolls averaged 6 percent for depths of 0–20 inches, 5 percent for depths of 20–60 inches, and 0 percent below 60 inches. The soil database also indicated that no root-restricting zones were identified in the top 60 inches of the soil units for these five atolls. Accordingly, for our water-budget model for Roi-Namur, available water capacity of the soil was set to 5 percent for the top 60 inches of soil for all subareas of the Roi-Namur water-budget model. Actual ET for one subarea (Subarea_ID 68) includes evapotranspiration of surplus catchment water that was discharged to the ground during 2009–2012 (see description for SC_Water). On Roi-Namur, surplus catchment water was discharged to the ground from equipment at a few vertical wells distributed in an oval-shaped swale, represented by the subarea with Subarea_ID 68, above a horizontal skimming well. For our estimates of evapotranspiration of surplus catchment water, we assumed that surplus catchment water was discharged uniformly onto the ground within five circles, each with a 50-ft radius, centered at points assumed to represent five vertical wells distributed in the swale above the horizontal skimming well. Actual ET estimated in this manner was 5 percent of the total catchment water discharged onto the ground during 2009–12. Producer defined 0.129 7.105 Inches Total_ET Monthly total evapotranspiration, in inches. Monthly total evapotranspiration (ET) was summed from daily total ET values. Daily total ET equaled the sum of canopy evaporation and actual ET. Producer defined 0.24 7.096 Inches Ntrl_Rech Monthly natural recharge, in inches, from rainfall. Excludes recharge from surplus catchment water (SC_Water) that was discharged to the ground. Monthly natural recharge was summed from daily natural recharge. Daily natural recharge for all subareas was computed using equations 1–15 in USGS SIR 2014-5168 and using input data described in this metadata file. Producer defined 0 15.263 Inches Artfl_Rech Monthly artificial recharge, in inches, from surplus catchment water discharged to the ground (SC_Water). Excludes natural recharge from rainfall, and considered for one subarea (Subarea_ID 68) only. Artificial recharge from surplus catchment water was assumed to equal the difference between the amount of surplus catchment water discharged to the ground (SC_water) and the amount of actual ET of SC_water (see description for Actual_ET). Producer defined 0 34.258 Inches Total_Rech Monthly total recharge, in inches. Equals the sum of natural recharge (Ntrl_Rech) from rainfall and artificial recharge (Artfl_Rech) from surplus catchment water discharged to the ground (see descriptions of Ntrl_Rech and Artfl_Rech). Only one subarea (Subarea_ID 68) has artificial recharge values that are greater than 0. The remaining subareas have natural recharge only. Producer defined 0 40.840 Inches The entity and attribute information provided here describes the tabular data associated with the data set. Please review the detailed descriptions that are provided (the individual attribute descriptions) for information on the values that appear as fields/table entries of the data set. The minimum and maximum values reported here indicate the range of values for all 156 shapefiles in the zipped folder "Monthly_water_budget_Roi-Namur_2000-12.zip". The entity and attribute information was generated by the individual and/or agency identified as the originator of the data set. Please review the rest of the metadata record for additional details and information. U.S. Geological Survey Michael Ierardi IT Specialist mailing

445 National Center

Reston VA 20192 1-888-275-8747 (1-888-ASK-USGS) mierardi@usgs.gov Although this data set has been used by the U.S. Geological Survey, U.S. Department of the Interior, no warranty expressed or implied is made by the U.S. Geological Survey as to the accuracy of the data and related materials. The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the U.S. Geological Survey in the use of this data, software, or related materials. Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Shape Online accessible data WinZip compressed file 0.11 https://water.usgs.gov/GIS/dsdl/Monthly_water_budget_Roi-Namur_2000-12.zip None. This dataset is provided by USGS as a public service. 20201117 U.S. Geological Survey Ask USGS -- Water Webserver Team mailing

445 National Center

Reston VA 20192 1-888-275-8747 (1-888-ASK-USGS) mierardi@usgs.gov FGDC Content Standards for Digital Geospatial Metadata FGDC-STD-001-1998