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Monthly Climate Data for Selected USGS HCDN Sites, 1951-1990, R1
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Summary:

Time series of monthly minimum and maximum temperature, precipitation, and potential evapotranspiration were derived for 1,469 watersheds in the conterminous United States for which stream flow measurements were also available from the national streamflow database, termed the Hydro-Climatic Data Network (HCDN), developed by Slack et al. (1993a,b). Monthly climate estimates were derived for the years 1951-1990.

The climate characteristic estimates of temperature and precipitation were estimated using the PRISM (Daly et al. 1994, 1997) climate analysis system as described in Vogel, et al. 1999.

Estimates of monthly potential evaporation were obtained using a method introduced by Hargreaves and Samani (1982) which is based on monthly time series of average minimum and maximum temperature data along with extraterrestrial solar radiation. Extraterrestrial solar radiation was estimated for each basin by computing the solar radiation over 0.1 degree grids using the method introduced by Duffie and Beckman (1980) and then summing those estimates for each river basin. This process is described in Sankarasubramanian, et al. (2001).

The data files are organized in directories by parameter, Tmax, Tmin, Pre, or PET, with each of the four directories containing 18 subdirectories representing the 18 Water Resources Council regions for the conterminous United States. Each region subdirectory contains data files for the monthly time series of respective hydroclimate attributes (Tmax, Tmin, Precipitation, and PET) for the individual basins in that region for the years 1951-1990. All files are in space delimited ASCII format.

Revision Notes: This data set has been revised to update the number of watersheds included in the data set and to updated the units for the potential evapotranspiration variable.  Please see the Data Set Revisions section of this document for detailed information.

Data Citation:

Cite this data set as follows:

Vogel, R.M., and A. Sankarasubramanian. 2015. Monthly Climate Data for Selected USGS HCDN Sites, 1951-1990, R1. ORNL DAAC Oak Ridge, Tennessee, USA. http://dx.doi.org/10.3334/ORNLDAAC/810.

This data set was originally published as:

Vogel, R. M., and A.Sankarasubramanian. 2005. Monthly Climate Data for Selected USGS HCDN Sites, 1951-1990. Data set. Available on-line [http://www.daac.ornl.gov] from Oak Ridge National Laboratory Distributed Active Archive Center, Oak Ridge, Tennessee, U.S.A. http://dx.doi.org/10.3334/ORNLDAAC/810.

Table of Contents:

1. Data Set Overview:

Project: Hydroclimatology

Time series of monthly minimum and maximum temperature, precipitation, and potential evapotranspiration were derived for 1,469 watersheds in the conterminous United States for which stream flow measurements were also available from the national streamflow database, termed the Hydro-Climatic Data Network (HCDN), developed by Slack et al. (1993a,b). Monthly climate estimates were derived for the years 1951-1990.

The climate characteristic estimates of temperature and precipitation were estimated using the PRISM (Daly et al. 1994, 1997) climate analysis system as described in Vogel, et al. 1999.

Estimates of monthly potential evaporation were obtained using a method introduced by Hargreaves and Samani (1982) which is based on monthly time series of average minimum and maximum temperature data along with extraterrestrial solar radiation. Extraterrestrial solar radiation was estimated for each basin by computing the solar radiation over 0.1 degree grids using the method introduced by Duffie and Beckman (1980) and then summing those estimates for each river basin. This process is described in Sankarasubramanian, et al. (2001).

The data files are organized in directories by parameter, Tmax, Tmin, Pre, or PET, and with each of hte four directories containing18 subdirectories representing the 18 Water Resources Council regions for the conterminous United States. Each region subdirectory contains data files for the monthly time series of respective hydroclimate attributes (Tmax, Tmin, Precipitation, or PET) for the individual basins in that region for the years 1951-1990.

2. Data Characteristics:

Data Format:

The data files are organized in directories by parameter, Tmax, Tmin, Pre, or PET, and contain 18 subdirectories representing the 18 Water Resources Council regions (Region--, -- represents the region number). See description below.

Each region subdirectory contains data files for the monthly time series of respective hydroclimate attributes (Tmax, Tmin, Precipitation, and PET) for the individual sites in that region for the years 1951-1990. File names are identified by the unique number id of the HCDN station located within each watershed. All files are in space delimited ASCII format.

Parameter Description and Units
Pre Precipitation in mm/month
PET Potential evapotranspiration in mm/month
Tmax Average maximum monthly temperature in tenths of degree Celsius (e.g., -40.6250 *0.1 = -4.06250 degree Celsius)
Tmin Average minimum monthly temperature in tenths of degree Celsius (e.g., see Tmax)

Example data records: Maximum Temperature for Region 10, HCDN Station 6019500. File name: 6019500.tmax

Columns: Station Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

 

   6019500 1951 -40.6250 13.8750 16.0625 100.7500 157.4375 159.8750 255.8125 218.8125 184.7500 84.8125 20.7500 -44.1875

   6019500 1952 -34.0625 -10.5625 7.1875 116.8125 155.1250 203.9375 241.0000 247.1875 226.5000 165.3750 5.0000 -11.3750

...

   6019500 1989 -21.8750 -58.4375 46.6875 109.6250 145.1250 203.6250 272.8125 223.6250 198.4375 103.5000 46.5000 -0.8750

   6019500 1990 -2.3125 2.1250 55.3125 122.8125 135.7500 196.4375 254.8125 247.0000 239.4375 111.3750 47.1250 -64.6875

 

Companion Files

Watershed Characteristics

In the file, HCDN_watershed_characteristics.zip, a companion file of detailed HCDN watershed characteristics (HCDN_watershed_characteristics.csv) and a documentation file (hcdn_watershed_char_desc.pdf) are provided.

A companion file of detailed HCDN watershed characteristics (HCDN_watershed_characteristics.csv) and a documentation file (hcdn_watershed_char_desc.pdf) are provided.

Selected HCDN Sites

In the file selected_HCDN_stations.zip, the companion file Selected_HCDN_stations.zip_20050601.csv provides station information for 1,376 HCDN sites corresponding to this data set. This information is subset from the master HCDN station data file available online from USGS. Format and content descriptions are contained in the documentation file hcdn_stations_fmt_desc.pdf.

3. Data Application and Derivation:

These data could be used in climate models.

4. Quality Assessment:

Not available.

5. Data Acquisition Materials and Methods:

A subset of the HCDN streamflow sites from watersheds with at least 10 years of record length were used in this study. Overall, the HCDN data set consists of records of average daily streamflow at 1,553 sites located throughout the United States. The data meet certain measurement accuracy criterion outlined by Slack et al. (1993). The HCDN contains river flows from 1874 to 1988, with an average record length of 44 years. The streamflow data included in the HCDN are relatively free from anthropogenic influences and the accuracy ratings of these records are at least rated good per USGS standards.

Water Resources Council Regions

The monthly climate data are organized by United States Water Resources Council Regions. The United States Geologic Survey (USGS) has divided and sub-divided the US into successively smaller hydrologic units. The first and broadest level of classification divides the U.S. into 21 Water-Resources Council Regions. For a more comprehensive explanation of ththese divisions, refer to "Hydrologic units, hydrologic unit codes, and hydrologic unit names" ( http://pubs.usgs.gov/of/1992/ofr92-129/files/hucs.html ).

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Region 16

The gray lines are state lines, the blue lines are major rivers, and the white lines are water-resources region boundary lines. This data set only has data for the 18 regions of the conterminous United States.

Region 01: New England
Region 02: Mid-Atlantic
Region 03: South Atlantic-Gulf
Region 04: Great Lakes
Region 05: Ohio
Region 06: Tennessee
Region 07: Upper Mississippi
Region 08: Lower Mississippi
Region 09: Souris-Red-Rainy
Region 10: Missouri
Region 11: Arkansas-White-Red
Region 12: Texas-Gulf
Region 13: Rio Grande
Region 14: Upper Colorado
Region 15: Lower Colorado
Region 16: Great Basin
Region 17: Pacific Northwest
Region 18: California
Region 19: Alaska
Region 20: Hawaii
Region 21: Caribbean

6. Data Access:

This data is available through the Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC).

Data Archive Center:

Contact for Data Center Access Information:
E-mail: uso@daac.ornl.gov
Telephone: +1 (865) 241-3952

7. References:

Daly, C., Neilson, R. P., and Phillips, D. L. (1994). A statistical-topographic model for mapping climatological precipitation over mountainous terrain. J. Appl. Meteorology, 33(2), 140-158.

Daly, C., Taylor, G., and Gibson, W. (1997). The PRISM approach to mapping precipitation and temperature. Proc., 10th AMS Conf. on Appl. Climatology, American Meteorological Society, Boston, Mass.

Duffie, J. A., and W. A. Beckman. 1980. Solar Engineering of Thermal Processes. John Wiley, New York, pp. 1-109.

Hargreaves, G. H., and Z. A. Samani. 1982. Estimating potential evapotranspiration, J. Irrig. Drain. Eng., 108(3), 225-230.

Sankarasubramanian, A., and R. M. Vogel. 2002. Annual hydroclimatology of the United States. Water Resources Res., 38(6), 1083, doi:10.1029/ 2001WR000619.

Sankarasubramanian, A., R. M. Vogel, and J. F. Limbrunner. 2001. Climate elasticity of streamflow in the United States. Water Resources Res., 37(6), doi:10.1029/2000WR900330.

Slack, J. R., A. M. Lumb, and J. M. Landwehr. 1993a. Hydroclimatic data network (HCDN): A U.S. Geological Survey streamflow data set for the United States for the study of climate variation, 1874-1988. Water Resour. Invest. Rep., 93-4076.

Slack, J. R., A. Lumb, and J. M. Landwehr. 1993b. Hydro-Climatic Data Network (HCDN) Streamflow Data Set, 1874-1998. CD-ROM. U.S. Geological Survey, Reston, Virginia, U.S.A. Available from Oak Ridge National Laboratory Distributed Active Archive Center, Oak Ridge, Tennessee, U.S.A. [http://www.daac.ornl.gov].

Vogel, R. M., I. Wilson, and C. Daly. 1999. Regional regression models of annual streamflow for the United States, J. Irrig. Drainage Eng., 125(3), 148-157.

8. Data Set Revisions:

Revision Summary:

The number of watersheds included in this data set has been updated to 1,469. In the original documentation, the number of watersheds was listed as 1,337.

The units for the variable PET, Potential evapotranspiration, have been updated to mm/month. In the original data set, the units for PET were in mm/day.