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African Water Stress Study

Federal Geographic Data Committee (FGDC) Metadata:


Identification_Information:
Citation:
Citation_Information:
Originator: Water Systems Analysis Group
Publication_Date: Unknown
Title: African Water Stress Study
Edition:
Geospatial_Data_Presentation_Form:
Series_Information:
Series_Name: World Water Development Report II
Issue_Identification:
Publication_Information:
Publication_Place: Durham, NH
Publisher: University of New Hampshire
Other_Citation_Details:
Online_Linkage: http://wwdrii.sr.unh.edu/download.html
Description:
Abstract:
Outputs from a Water Balance and Transport Model (WBM/WTM) were used to determine the spatial distribution of renewable water supply, expressed as the sum of local runoff and river corridor discharge. Monthly atmospheric forcings from 1960-95 were from (New et al., 1998). Estimates of domestic and industrial water demands (Vorosmarty et al., 2000a; 2004) were apportioned by urban/rural population densities. Agricultural withdrawals were based on African water statistics (Jippe Hoogeveen, FAO/AGL, Rome Italy) at the sub-basin level, and a mapping of irrigation-equipped lands (Siebert et al., 2002). All supply and demand estimates were resampled as required and georegistered to a 6 min grid and river network (STN-06), updated from a previous flow topology (Vorosmarty et al., 2000b) using a network rescaling algorithm that processed 1-km digital streamlines (Fekete et al., 2001). STN-06 basin boundaries were compared to a hand-corrected database provided by FAO. Water scarcity was evaluated, in part, by computing the Climatic Moisture Index (CMI, Willmott and Feddema, 1992), the ratio of annual precipitation (P) to annual potential evapotranspiration, (PET). Specifically CMI = (P / PET) -1 when P < PET and CMI = 1 - (PET/P) when P = PET. The CMI ranges from -1 to +1 , with wet climates showing positive values, dry climates negative. PET was estimated using a physically based function (Shuttleworth and Wallace, 1985). We grouped CMI into major climate categories following Koppen. The coefficient of variation (CV) computed for all variables is the ratio of the standard deviation to the mean over the time series analyzed. Water supply in each grid cell (n) has two sources: locally-generated discharge (QLn) and river corridor discharge (QCn), which enters from upstream cells. QLn is the product of runoff (Rn) and cell area (An). QCn accumulates QLn in a downstream direction along the STN-06 digital nertwork. Cells with mean upstream runoff < 3 mm yr-1 were considered inactive or non-perennially discharging (Vorosmarty et al., 2000b). Water use is represented by local demand (DIAn), the sum of domestic, industrial and agricultural water withdrawals. Dividing DIAn by QCn yields an index of local relative water use. A high degree of stress is indicated when the relative water use index is > 0.4 or 40% (34). DIAn summed in a downstream direction (in a similar manner as QCn) and divided by QCn is called the water reuse index and represents the extent to which runoff is recycled or reused as it accumulates and flows toward the basin mouth. The water reuse index typically increases in a downstream direction, indicating reuse and recycling of river corridor water. This index can, however, decrease when mainstream flow is diluted by more pristine (less-recycled) tributary waters. Downloadable files include: - Agricultural area in km2: Spatial distribution of agricultural area per grid cell (in km2 per grid cell): FAO/AGL, Rome Italy. - Annual CMI, mean: Mean annual climate moisture index computed from 1960-1995 annual time series: Willmott and Feddema, 1992. - Annual CMI, coefficient of variabiltiy (CV): Interannual variability of the CMI, as represented by the CV, which is computed as the standard deviation divided by the mean: Willmott and Feddema, 1992. - Domestic + industrial + agricultural water use, 1995 (DIA, in km3/yr): Sum of human water use in 1995 in km3/yr per grid cell: Vorosmarty et al., 2005. - Annual discharge (Q), mean in km3/yr. Long-term average annual river flow (discharge, Q) computed from the 1960-1995 time series: Vorosmarty et al., 2005. - Annual discharge (Q), 30-yr low in km3/yr.Minimum annual river flow (discharge, Q) selected from the 1960-1995 time series: Vorosmarty et al., 2005. - Annual discharge (Q), annual coefficient of variability (CV). Interannual variability of discharge, as represented by the CV, which is computed as the standard deviation divided by the mean: Vorosmarty et al., 2005. - Seasonal variability, ratio of monthly maximum to monthly minimum (Q maxmin): Ratio of monthly maximum discharge to monthly minimum discharge, representing the range of intra-annual discharge variability: Vorosmarty et al., 2005. - Irrigated area: Spatial distribution of irrigation-equipped area (in km2 per grid cell), aggregated to 6-min (latitude by longitude) resolution. Primary source: Siebert et al., 2002. - Annual runoff, mean: Mean annual runoff (in mm/yr per grid cell) computed from 1960-1995 annual time series: Vorosmarty et al., 2005. - Annual runoff, coefficient of variability: Interannual variability of runoff, as represented by the CV, which is computed as the standard deviation divided by the mean: Vorosmarty et al., 2005. - Relative water stress index (RWSI), mean annual Q: Ratio of domestic + industrial + agricultural water use in 1995 (DIA) to long-term mean annual discharge (Q). Water stress is indicated when RWSI is greater than or equal to 0.4: Vorosmarty et al., 2005. - Relative water stress index (RWSI), 30-yr low Q: Ratio of domestic + industrial + agricultural water use in 1995 (DIA) to 30 year low discharge (Q): Vorosmarty et al., 2005. - Months with RWSI exceeding 0.4. Number of months within an average years during which the RWSI equals or exceeds 0.4: Vorosmarty et al., 2005. - Number of people exposed to water stress: Number of people (per grid cell) within grid cells that experience RWSI equal to or greater than 0.4, on an average annual basis: Vorosmarty et al., 2005. - Number of people exposed to water stress: Number of people (per grid cell) within grid cells that experience RWSI equal to or greater than 0.4, for the 30 year minimum discharge: Vorosmarty et al., 2005. - Water reuse index (WRI), mean annual. Water reuse index is computed as the ratio of cumulative DIA to mean annual discharge, representing the degree to which river water is reused by humans as it flows along a river network: Vorosmarty et al., 2005.
Purpose:
Not Available
Supplemental_Information:
REFERENCE: Fekete, B.M., Vorosmarty, C.J. and Lammers, R.B. 2001. Scaling gridded river networks for macroscale hydrology: Development, analysis, and control of error. Water Resources Research 37:7 1955-1967.
Supplemental_Information:
REFERENCE: New, M., Hulme, M. and Jones, P. 1998. Representing twentieth century space-time climate variability. Part II: Development of 1901-1996 monthly grids. J. Climate 13: 2217-2238.
Supplemental_Information:
REFERENCE: Shuttleworth, W.J. and Wallace, J.S. 1985. Evaporation from sparse crops: an energy combination theory, Quarterly J. R. Meteorol. Soc. 111: 839-855.
Supplemental_Information:
REFERENCE: Siebert S., DC6ll, P. and Hoogeveen, J. 2002. Global map of irrigated areas version 2.1 Center for Environmental Systems Research, University of Kassel, Germany / Food and Agriculture Organization of the United Nations, Rome, Italy.
Supplemental_Information:
REFERENCE: Willmott, C.J., and Feddema, J.J. 1992. A more rational climatic moisture index. Prof. Geographer 44: 84-87.
Supplemental_Information:
REFERENCE: Vorosmarty, C. J., E.M. Douglas, P. A. Green and C. Revenga, Geospatial indicators of emerging water stress: an application in Africa, Ambio, in press, 2005.
Supplemental_Information:
REFERENCE: Vorosmarty, C.J., Brunner, J., Revenga, C., Fekete, B., Green, P., Kura, Y. and Thompson, K. 2004. Case studies: Population and climate. In: Kabat, P., Claussen, M., Dirmeyer, P.A., Gash, J.H.C., Bravo de Guenni, L., Meybeck, M., Pielke Sr., R.A., Vorosmarty, C.J., Hutjes, R.W.A. and Lutkemeier, S. (eds), Vegetation, Water, Humans and the Climate. Springer, Heidelberg, Germany.
Supplemental_Information:
REFERENCE: Vorosmarty, C.J., Green, P., Salisbury, J. and Lammers, R. 2000a. Global water resources: Vulnerability from climate change and population growth. Science 289, 284-288.
Supplemental_Information:
REFERENCE: Vorosmarty, C.J., Fekete, B.M., Meybeck, M., Lammers, R. 2000b. A simulated topological network representing the global system of rivers at 30-minute spatial resolution (STN-30). Global Biogeochemical Cycles 14, 599-621.
Time_Period_of_Content:
Time_Period_Information:
Range_of_Dates/Times:
Beginning_Date: 19600101
Ending_Date: 19951231
Currentness_Reference:Unknown
Status:
Progress: Complete
Maintenance_and_Update_Frequency: As needed
Spatial_Domain:
Description_of_Geographic_Extent:
Bounding_Coordinates:
West_Bounding_Coordinate: -10.0
East_Bounding_Coordinate: 60.0
North_Bounding_Coordinate: 40.0
South_Bounding_Coordinate: -35.0
Keywords:
Theme:
Theme_Keyword_Thesaurus: GCMD SCIENCE PARAMETERS
Theme_Keyword_Thesaurus: PROJECT
Theme_Keyword_Thesaurus: ANCILLARY KEYWORDS
Theme_Keyword_Thesaurus: ISO TOPIC CATEGORY
Theme_Keyword_Thesaurus: DATA SET LANGUAGE
Theme_Keyword: EARTH SCIENCE > ATMOSPHERE > ATMOSPHERIC WATER VAPOR > EVAPOTRANSPIRATION > POTENTIAL EVAPOTRANSPIRATION
Theme_Keyword: EARTH SCIENCE > BIOSPHERE > TERRESTRIAL ECOSYSTEMS > AGRICULTURAL LANDS
Theme_Keyword: EARTH SCIENCE > HUMAN DIMENSIONS > HABITAT CONVERSION/FRAGMENTATION > IRRIGATION
Theme_Keyword: EARTH SCIENCE > HUMAN DIMENSIONS > ENVIRONMENTAL GOVERNANCE/MANAGEMENT > WATER MANAGEMENT
Theme_Keyword: EARTH SCIENCE > TERRESTRIAL HYDROSPHERE > SURFACE WATER > DISCHARGE/FLOW
Theme_Keyword: EARTH SCIENCE > TERRESTRIAL HYDROSPHERE > SURFACE WATER > RIVERS/STREAMS
Theme_Keyword: EARTH SCIENCE > TERRESTRIAL HYDROSPHERE > SURFACE WATER > RUNOFF
Theme_Keyword: EARTH SCIENCE > LAND SURFACE > LAND USE/LAND COVER > LAND COVER
Theme_Keyword: EARTH SCIENCE > HUMAN DIMENSIONS > SOCIAL BEHAVIOR > VULNERABILITY LEVELS/INDEX
Theme_Keyword: WWAP > WORLD WATER ASSESSMENT PROGRAMME
Theme_Keyword: Water Use
Theme_Keyword: Water Re-use
Theme_Keyword: Water Stress
Theme_Keyword: Relative Water Stress Index (rwsi)
Theme_Keyword: Climate Moisture Index (cmi)
Theme_Keyword: Agricultural Water Use
Theme_Keyword: Industrial Water Use
Theme_Keyword: Domestic Water Use
Theme_Keyword: Potential Evapotranspiration
Theme_Keyword: Pet
Theme_Keyword: World Water Asessment Programme
Theme_Keyword: World Water Development Report Ii
Theme_Keyword: FARMING
Theme_Keyword: ENVIRONMENT
Theme_Keyword: IMAGERY/BASE MAPS/EARTH COVER
Theme_Keyword: INLAND WATERS
Theme_Keyword: ENGLISH
Place:
Place_Keyword_Thesaurus: GCMD
Place_Keyword: CONTINENT > AFRICA
Access_Constraints: Not Available
Use_Constraints:
Not Available
Point_of_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: CHARLES J. VOROSMARTY
Contact_Position: INVESTIGATOR
Contact_Address:
Address_Type: Mailing and Physical Address
Address: Water Systems Analysis Group
Address: Complex Systems Research Center
Address: Institute for the Study of Earth, Oceans, and Space
Address: University of New Hampshire
Address: Morse Hall, 39 College Road
City: DURHAM
State_or_Province: NH
Postal_Code: 03824
Country: USA
Contact_Voice_Telephone: (603) 862-1792
Contact_Facsimile_Telephone: (603) 862-0188
Contact_Electronic_Mail_Address: charles.vorosmarty@unh.edu
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Data_Quality_Information:
Attribute_Accuracy:
Attribute_Accuracy_Report:
Not Available
Logical_Consistency_Report:
Not Available
Completeness_Report:
Not Available
Lineage:
Process_Step:
Process_Description:
Not Available
Process_Date: Unknown
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Spatial_Reference_Information:
Horizontal_Coordinate_System_Definition:
Geographic:
Latitude_Resolution: 6 min
Longitude_Resolution: 6 min
Geographic_Coordinate_Units: Decimal degrees
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Distribution_Information:
Distributor:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: UNH/EOS/CSRC/WATSYS > Water Systems Analysis Group, Complex Systems Research Center, Institute for the Study of Earth, Oceans, and Space, University of New Hampshire
Contact_Person: CHARLES J. VOROSMARTY
Contact_Position: DATA CENTER CONTACT
Contact_Address:
Address_Type: Mailing and Physical Address
Address: Water Systems Analysis Group
Address: Complex Systems Research Center
Address: Institute for the Study of Earth, Oceans, and Space
Address: University of New Hampshire
Address: Morse Hall, 39 College Road
City: DURHAM
State_or_Province: NH
Postal_Code: 03824
Country: USA
Contact_Voice_Telephone: (603) 862-1792
Contact_Facsimile_Telephone: (603) 862-0188
Contact_Electronic_Mail_Address: charles.vorosmarty@unh.edu
Resource_Description: UNH_WWRDII_AFRICA
Distribution_Liability:
Not Available
Standard_Order_Process:
Digital_Form:
Digital_Transfer_Information:
Format_Name: JPEG, ascii, ARC
Digital_Transfer_Option:
Online_Option:
Computer_Contact_Information:
Network_Address:
Network_Resource_Name:
http://www.wsag.unh.edu/
Access_Instructions:
DATA CENTER URL
Digital_Transfer_Option:
Online_Option:
Computer_Contact_Information:
Network_Address:
Network_Resource_Name:
http://wwdrii.sr.unh.edu/download.html
Access_Instructions:
Access to African water stress study data
Digital_Transfer_Option:
Online_Option:
Computer_Contact_Information:
Network_Address:
Network_Resource_Name:
http://wwdrii.sr.unh.edu/sourcematerial/Africa_met...
Access_Instructions:
Access to documentation
Fees: None
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Metadata_Reference_Information:
Metadata_Date: 20051212
Metadata_Review_Date: 20121102
Metadata_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: GCMD User Support Office
Contact_Organization: NASA Global Change Master Directory
Contact_Address:
Address_Type: Mailing and Physical Address
Address: Not Available
City: Lanham
State_or_Province: MD
Postal_Code: 20706
Country: USA
Contact_Voice_Telephone: Not Available
Contact_Electronic_Mail_Address: gcmduso@gcmd.gsfc.nasa.gov
Metadata_Standard_Name: FGDC Content Standards for Digital Geospatial Metadata
Metadata_Standard_Version: FGDC-STD-001-1998
Metadata_Time_Convention: local time
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