,The Southern Great Plains 1997 (SGP97) Hydrology Experiment originated from an interdisciplinary investigation, "Soil Moisture Mapping at Satellite Temporal and Spatial Scales" (PI: Thomas J. Jackson, USDA Agricultural Research Service, Beltsville, MD) selected under the NASA Research Announcement 95-MTPE-03. The NESOB 1997 Daily Precipitation Composite is one of several precipitation datasets provided in the Global Energy and Water Cycle Experiment (GEWEX) Continental-Scale International Project (GCIP) Near-Surface Observation Data Set (NESOB) 1997. This precipitation composite is composed of data from several sources (i.e., National Weather Service (NWS) Cooperative Observers, National Centers for Environmental Prediction (NCEP), and the daily precipitation data extracted from the NESOB 1997 Hourly Precipitation Composite). Data from these sources were quality controlled and merged to form this precipitation composite. After the datasets were merged to form the NESOB 1997 Daily Precipitation Composite, a statistics program was executed to ensure that the quality of the individual datasets had been retained. This composite contains data for the NESOB 1997 domain (approximately 94.5 W to 100.5 W longitude and 34 N to 39 N latitude) and time period (01 April 1997 through 31 March 1998). The NCEP Daily Precipitation dataset was formed by extracting incremental precipitation values. The value reported for any daily observation represents data collected during the previous 24 hours. The Daily Precipitation Composite contains six metadata parameters and four data parameters. The metadata parameters describe the station location and time at which the data were collected. The four data parameters repeat once for each day in the monthly record. Every record has 31 days reported, regardless of the actual number of days in the month. For months with less than 31 days, the extra days are reported as missing (i.e., '-999.99 7 M'). Each 24 hour precipitation value has an associated observation hour. The observation hour is the ending UTC hour for the 24 hour period for which the precipitation value is valid.,

,The Southern Great Plains 1997 (SGP97) Hydrology Experiment originated from an interdisciplinary investigation, "Soil Moisture Mapping at Satellite Temporal and Spatial Scales" (PI: Thomas J. Jackson, USDA Agricultural Research Service, Beltsville, MD) selected under the NASA Research Announcement 95-MTPE-03. The Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) Global Energy and Water Cycle Experiment (GEWEX) Continental-Scale International Project (GCIP) Near-Surface Observation Data Set (NESOB) 1997 Hourly Surface Composite is composed of data from several sources (i.e., Automated Surface Observing System (ASOS), Department Of Energy (DOE) Atmospheric Radiation Measurement Surface (ARMSFC), National Oceanic and Atmospheric Administration (NOAA) Wind Profiler Network (NPN), High Plains Climate Network (HPCN), National Climatic Data Center (NCDC) DATSAV3, and the NOAA Atmospheric Turbulence and Diffusion Division (ATDD) Little Washita Meteorological site for the ARM/GCIP NESOB 1997 domain. Data from these sources (approximately 100 stations) were merged and quality controlled to form this Surface Composite. This Surface Composite contains data for the ARM/GCIP NESOB 1997 time period (01 April 1997 through 31 March 1998) and for the ARM/GCIP NESOB 1997 domain only. The ARM/GCIP NESOB 1997 domain is approximately 34N to 39N latitude and 94.5W to 100.5W longitude. The ARM/GCIP NESOB 1997 Hourly Surface Composite contains ten metadata parameters and 38 data parameters and flags. The metadata parameters describe the station location and time at which the data were collected. The time of observation is reported both in Universal Time Coordinated (UTC) Nominal and UTC actual time. Days begin at UTC hour 0100 and end at UTC hour 0000 the following day. The data parameters are valid for the reported times. Missing values are reported as 9's in the data field. Several data parameters have an associated Quality Control (QC) Flag Code which is assigned during the Joint Office for Science Support (JOSS) quality control processing; data were never changed, only flagged. When not present in the raw data, the dewpoint is computed using the formula from Bolton (1980). Calculated Sea Level pressure is computed from station pressure, temperature, dewpoint, and station elevation using the formula of Wallace and Hobbs (1977). Specific Humidity values were computed from dew point and station pressure using formulas from Wexler and Wildhack (1963). The squall/gust wind speed data were not quality controlled.,

,The Southern Great Plains 1997 (SGP97) Hydrology Experiment originated from an interdisciplinary investigation, "Soil Moisture Mapping at Satellite Temporal and Spatial Scales" (PI: Thomas J. Jackson, USDA Agricultural Research Service, Beltsville, MD) selected under the NASA Research Announcement 95-MTPE-03. The NESOB 1997 Daily Precipitation Composite is one of several precipitation datasets provided in the Global Energy and Water Cycle Experiment (GEWEX) Continental-Scale International Project (GCIP) Near-Surface Observation Data Set (NESOB) 1997. This precipitation composite is composed of data from several sources (i.e., National Weather Service (NWS) Cooperative Observers, National Centers for Environmental Prediction (NCEP), and the daily precipitation data extracted from the NESOB 1997 Hourly Precipitation Composite). Data from these sources were quality controlled and merged to form this precipitation composite. After the datasets were merged to form the NESOB 1997 Daily Precipitation Composite, a statistics program was executed to ensure that the quality of the individual datasets had been retained. This composite contains data for the NESOB 1997 domain (approximately 94.5 W to 100.5 W longitude and 34 N to 39 N latitude) and time period (01 April 1997 through 31 March 1998). The NCEP Daily Precipitation dataset was formed by extracting incremental precipitation values. The value reported for any daily observation represents data collected during the previous 24 hours. The Daily Precipitation Composite contains six metadata parameters and four data parameters. The metadata parameters describe the station location and time at which the data were collected. The four data parameters repeat once for each day in the monthly record. Every record has 31 days reported, regardless of the actual number of days in the month. For months with less than 31 days, the extra days are reported as missing (i.e., '-999.99 7 M'). Each 24 hour precipitation value has an associated observation hour. The observation hour is the ending UTC hour for the 24 hour period for which the precipitation value is valid.,

,The Southern Great Plains 1997 (SGP97) Hydrology Experiment originated from an interdisciplinary investigation, "Soil Moisture Mapping at Satellite Temporal and Spatial Scales" (PI: Thomas J. Jackson, USDA Agricultural Research Service, Beltsville, MD) selected under the NASA Research Announcement 95-MTPE-03. The Fifteen Minute Precipitation Composite is one of several precipitation datasets provided in the Global Energy and Water Cycle Experiment (GEWEX) Continental-Scale International Project (GCIP) Near-Surface Observation Data Set (NESOB) 1997. This precipitation composite was formed from two data sources (National Climatic Data Center (NCDC) Fifteen Minute Precipitation data (TD 3260), and fifteen minute precipitation extracted from the Department Of Energy (DOE) Atmospheric Radiation Measurement Surface (ARMSFC) five minute surface data). Data from these sources were quality controlled and merged to form this precipitation composite. This composite contains data for the NESOB 1997 domain and time period (01 April 1997 through 31 March 1998). The NESOB 1997 domain is approximately 94.5W to 100.5 W longitude and 34N to 39 N latitude. Each 15-minute precipitation incremental value in this dataset was formed by summing the 5-minute precipitation values extracted from the Department Of Energy (DOE) Atmospheric Radiation Measurement Surface (ARMSFC) five minute surface data. The NESOB 1997 Fifteen Minute Precipitation Composite contains seven metadata parameters and three data parameters. The metadata parameters describe the date/time, network, station and location at which the data were collected. The three data parameters repeat once for each fifteen minutes from UTC 0000 through UTC hour 2345. Data reported for a designated 15-minute observation represents data collected during the previous 15-minutes. All times are reported in UTC, and precipitation data values are reported in millimeters.,

,The Southern Great Plains 1997 (SGP97) Hydrology Experiment originated from an interdisciplinary investigation, "Soil Moisture Mapping at Satellite Temporal and Spatial Scales" (PI: Thomas J. Jackson, USDA Agricultural Research Service, Beltsville, MD) selected under the NASA Research Announcement 95-MTPE-03. The temporal coverage for this dataset is as follows: Begin datetime: 1997-06-01 00:00:00, End datetime: 1997-07-31 23:59:59. The Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) program operates a Baseline Surface Radiation Network (BSRN) station at the Central Facility (located near Lamont, in north-central Oklahoma) of its Southern Great Plains site. BSRN provides 1-min observations of direct-beam normal solar irradiance, downwelling hemispheric diffuse solar irradiance, downwelling hemispheric solar irradiance and downwelling hemispheric infrared irradiance.,

,The Southern Great Plains 1997 (SGP97) Hydrology Experiment originated from an interdisciplinary investigation, "Soil Moisture Mapping at Satellite Temporal and Spatial Scales" (PI: Thomas J. Jackson, USDA Agricultural Research Service, Beltsville, MD) selected under the NASA Research Announcement 95-MTPE-03. The core of the 1997 experiment involves the deployment of the L-band Electronically Scanned Thinned Array Radiometer (ESTAR) for daily mapping of surface soil moisture. The region selected for investigation is the best instrumented site for surface soil moisture, hydrology and meteorology in the world. This includes the USDA/ARS Little Washita Watershed, the USDA/ARS facility at El Reno, Oklahoma, the ARM/CART central facility, as well as the Oklahoma Mesonet. The temporal coverage for this dataset is as follows: Begin datetime: 1995-10-01 00:00:00, End datetime: 2001-03-31 23:59:59. The Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) Southern Great Plains (SGP) Soil Bulk Density Data Set is one of the various sub-surface data sets developed for the ARM/GCIP (Global Energy and Water Cycle Experiment (GEWEX) Continental-scale International Project) 1996 Near-Surface Observation (NESOB-96) Data Set. This data set contains a summary table of the bulk densities representing the average of the values obtained from the soil water retention samples at each of the ARM SWATS (Soil Water and Temperature System) sites at the SGP site. The soil characterizations were perfomed by Oklahoma State University.,

,The Southern Great Plains 1997 (SGP97) Hydrology Experiment originated from an interdisciplinary investigation, "Soil Moisture Mapping at Satellite Temporal and Spatial Scales" (PI: Thomas J. Jackson, USDA Agricultural Research Service, Beltsville, MD) selected under the NASA Research Announcement 95-MTPE-03. The region selected for investigation is the best instrumented site for surface soil moisture, hydrology and meteorology in the world. This includes the USDA/ARS Little Washita Watershed, the USDA/ARS facility at El Reno, Oklahoma, the ARM/CART central facility, as well as the Oklahoma Mesonet. The National Climatic Data Center (NCDC) Summary of the Day Co-operative Dataset is one of several surface datasets provided for the Southern Great Plains (SGP) 1997 project. This NCDC Co-operative Observer (COOP) dataset contains data from sixty-two stations for the SGP 1997 time period (18 June 1997 through 18 July 1997) and in the SGP 1997 domain (approximately 97W to 99W longitude and 34.5N to 37N latitude). The primary thrust of the cooperative observing program is the recording of 24-hour precipitation amounts, but approximately 55% of the stations also record maximum and minimum temperatures. The observations are for the 24-hour period ending at the time of observation. Observer convenience or special program needs mean that observing times vary from station to station. However, the vast majority of observations are taken near either 7:00 AM or 7:00 PM local time. The NCDC Summary of the Day Co-operative Dataset (TD-3200) contains eight metadata parameters and fifteen data parameters and flags. The metadata parameters describe the date/time, network, station and location at which the data were collected. All times are UTC. Data values are valid for the 24 hours preceding the time of observation.,

,The Southern Great Plains 1997 (SGP97) Hydrology Experiment originated from an interdisciplinary investigation, "Soil Moisture Mapping at Satellite Temporal and Spatial Scales" (PI: Thomas J. Jackson, USDA Agricultural Research Service, Beltsville, MD) selected under the NASA Research Announcement 95-MTPE-03. The Continental-scale International Project (GCIP) Enhanced Observing Period (EOP) takes place in the Mississippi River basin, which provides a number of watershed areas that are potentially useful for hydrologic focused studies. The National Climatic Data Center (NCDC) Soil Temperature Dataset is one of several surface datasets provided for the Global Energy and Water-Balance Experiment (GEWEX) Continental-Scale International Project (GCIP) Near Surface Observation Data Set (NESOB) 1997 project. This dataset was formed by extracting soil temperature data from the GCIP/Enhanced Seasonal Observing Period 1997 (GCIP/ESOP-97) NCDC Summary of the Day Co-operative Dataset (TD-3200) for the NESOB 1997 area and time of interest. This NCDC Soil Temperature Dataset contains data from approximately 12 stations reporting soil temperature data for the NESOB 1997 time period (01 April 1997 through 31 March 1998) and in a domain slightly beyond that of NESOB 1997 (approximately 94.5W to 102W longitude and 34N to 39.5N latitude). The NCDC Soil Temperature Dataset contains seven metadata parameters and eighteen data parameters and flags. The metadata parameters describe the date, network, station and location at which the data were collected. Data values are valid for the 24 hours preceding the time of observation, and all times are UTC. Some stations may report soil temperatures at observation time twice a day. Separate records will occur for both observation times.,

,The Southern Great Plains 1997 (SGP97) Hydrology Experiment originated from an interdisciplinary investigation, "Soil Moisture Mapping at Satellite Temporal and Spatial Scales" (PI: Thomas J. Jackson, USDA Agricultural Research Service, Beltsville, MD) selected under the NASA Research Announcement 95-MTPE-03. The ARM Cloud and Radiation Testbed (CART) cloud height dataset is one of several datasets provided for the GEWEX Continental-Scale International Project (GCIP) Near-Surface Observing Period (NESOB) 1997 project. This dataset contains cloud height data collected using the ARMCART SGP Belfort Laser Ceilometer (BLC) Model 7013C and the ARMCART SGP MicroPulse Lidar (MPL) located at station E13: Lamont Central Facility 1 (CF1). This dataset contains data from these two instruments located within the NESOB 1997 domain (94.5 W to 100.5 W longitude and 34 N to 39 N latitude) for the NESOB 1997 time period (01 April 1997 through 31 March 1998). The data in this dataset were formed by extracting 30 minute cloud height data from 60 second BLC data in netCDF format. A zero for the first cloud layer signifies no clouds detected within the limit of the instrument field of view and range. A cloud ht of zero for the second and third cloud layers indicates an unknown cloud height (i.e. the ceiliometer can't see through lower clouds). These zeros are reported as "0.00000 U" in the data. The ARMCART Belfort Laser Ceilometer data contains eight metadata parameters and eight data parameters and flags. The metadata parameters describe the date, network, station and location at which the data were collected. Data values are collected at the time of observation. All times are UTC.,

,The Southern Great Plains 1997 (SGP97) Hydrology Experiment originated from an interdisciplinary investigation, "Soil Moisture Mapping at Satellite Temporal and Spatial Scales" (PI: Thomas J. Jackson, USDA Agricultural Research Service, Beltsville, MD) selected under the NASA Research Announcement 95-MTPE-03. The Global Energy and Water Cycle Experiment (GEWEX) Continental-scale International Project (GCIP) Enhanced Observing Period (EOP) takes place in the Mississippi River basin, which provides a number of watershed areas that are potentially useful for hydrologic focused studies. The temporal coverage for this dataset is as follows: Begin datetime: 1997-04-23 00:00:00, End datetime: 2001-12-31 23:59:59. This dataset contains the National Centers for Environmental Prediction (NCEP) Environmental Modeling Center (EMC) 4 KM GRIB radar estimate after bias removal ("UBR") data. A prototype, real-time, hourly, multi-sensor National Preciptation Analysis (NPA) has been developed at NCEP in cooperation with the Office of Hydrology (OH). This analysis merges two data sources that are currently being collected in real-time by OH and NCEP. Hourly digital precipitation (HDP) radar estimates are created by the WSR-88D Radar Product Generator on a 131 X 131 4-km grid centered over each radar site. Data analysis routines, including a bias correction of the radar estimates using rain gage data, have been adapted by NCEP on a national 4-km grid from algorithms developed by OH and executed regionally at NWS River Forecast Centers (RFC). This dataset only contains the NCEP 4 KM GRIB Data hourly, 6-hourly, and daily radar estimate after bias removal. 6-hourly data are generally available at 00Z, 06Z, 12Z, and 18Z. Daily data are generally available at 12Z. Depending on the time period selected, all three datasets may or may not be available. Other NCEP 4 KM GRIB Data including gage-only analysis, multi-sensor analysis (gage and unbiased radar), radar estimate (no bias removal), and gage-only analysis using 24h accumulated ("RFC") data are available as independent datasets. Depending on the time period selected, all five types may or may not be available. Please see GCIP/EOP: Surface NCEP Ancillary Catalogue of Available GCIP Precipitation Data (NCEP/EMC). The format of the files is GRIB. The files are compressed using the UNIX "compress" command and "uncompress" must be used before decoding.,