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Evaporation at LZ40 Platform, Lake Okeechobee, Palm Beach County, Florida, 2015

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What does this data set describe?

Title:
Evaporation at LZ40 Platform, Lake Okeechobee, Palm Beach County, Florida, 2015
Abstract:
Daily measurements of evaporation using the Bowen ratio method were made at USGS station name LZ40, a platform-based station constructed by the South Florida Water Management District (SFWMD) (26° 54" 06.254' N, 80° 47" 21.301' W). The associated USGS site number is 265405080472100. Data collection began on November 15, 2012. Meteorological and environmental variables were measured at 30-minute resolution until February 7, 2013 and 15-minute resolution thereafter to December 31, 2015, including: precipitation, air temperature, relative humidity, wind speed, net radiation, incoming solar radiation, and water temperature at various depths. The SFWMD also maintains meteorological and stage measurement equipment on the platform, and lake stage and precipitation were downloaded from the SFWMD web site DBHYDRO for use in the attached spreadsheet.
  1. How might this data set be cited?
    Michael A. Wacker and W. Barclay Shoemaker, 2016, Evaporation at LZ40 Platform, Lake Okeechobee, Palm Beach County, Florida, 2015: U.S. Geological Survey, Reston, VA.

    Online Links:

  2. What geographic area does the data set cover?
    West_Bounding_Coordinate: -80.78925
    East_Bounding_Coordinate: -80.78925
    North_Bounding_Coordinate: 26.901737
    South_Bounding_Coordinate: 26.901737
    Description_of_Geographic_Extent:
    Palm Beach County, Florida, platform located at the approximate center of Lake Okeechobee, South Florida Water Management District LZ40 Platform, 26° 54" 06.254' N, 80° 47" 21.301' W (NAD83), USGS station name LZ40.
  3. What does it look like?
  4. Does the data set describe conditions during a particular time period?
    Beginning_Date: 15-Nov-2012
    Ending_Date: 31-Dec-2015
    Currentness_Reference: ground condition
  5. What is the general form of this data set?
    Geospatial_Data_Presentation_Form: Excel spreadsheet
  6. How does the data set represent geographic features?
    1. How are geographic features stored in the data set?
    2. What coordinate system is used to represent geographic features?
  7. How does the data set describe geographic features?
    CR1000 Lake O Data
    Worksheet 1 (Source: https://sofia.usgs.gov/exchange/evapotrans/method.html)
    Floor
    Used for pivot table computation of daily values in worksheet 2 (Source: https://sofia.usgs.gov/exchange/evapotrans/method.html)
    Range of values
    Minimum:41228
    Maximum:42369
    Units:Unitless
    Timestamp
    Timestamp, date and local time EST (Eastern Standard Time) without daylight savings time applied (Source: https://sofia.usgs.gov/exchange/evapotrans/method.html) MM/DD/YYYY HH:MM
    RECORD
    Record, data record number, RN (Source: https://sofia.usgs.gov/exchange/evapotrans/method.html)
    Range of values
    Minimum:0
    Maximum:67768
    Units:Numeric code
    Shortwave Incoming
    Incoming shortwave radiation, averaged over timestep interval (30-minute resolution until February 7, 2013 and 15-minute resolution thereafter to December 31, 2015) (Source: https://sofia.usgs.gov/exchange/evapotrans/method.html)
    Range of values
    Minimum:0
    Maximum:1144
    Units:Watts per meter2
    Shortwave Outgoing
    Outgoing shortwave radiation, averaged over timestep interval (30-minute resolution until February 7, 2013 and 15-minute resolution thereafter to December 31, 2015) (Source: https://sofia.usgs.gov/exchange/evapotrans/method.html)
    Range of values
    Minimum:-7.806
    Maximum:111.6
    Units:Watts per meter2
    CNR1 Temperature
    Campbell Scientific Net Radiometer (CNR1) instrument temperature, averaged over timestep interval (30-minute resolution until February 7, 2013 and 15-minute resolution thereafter to December 31, 2015)e (Source: https://sofia.usgs.gov/exchange/evapotrans/method.html)
    Range of values
    Minimum:5.007
    Maximum:41.96
    Units:degrees Celsius
    Longwave Incoming
    Incoming longwave radiation, averaged over timestep interval (30-minute resolution until February 7, 2013 and 15-minute resolution thereafter to December 31, 2015) (Source: https://sofia.usgs.gov/exchange/evapotrans/method.html)
    Range of values
    Minimum:219.8
    Maximum:547.2
    Units:Watts per meter2
    Longwave Outgoing
    Outgoing longwave radiation, averaged over timestep interval (30-minute resolution until February 7, 2013 and 15-minute resolution thereafter to December 31, 2015) (Source: https://sofia.usgs.gov/exchange/evapotrans/method.html)
    Range of values
    Minimum:367.4
    Maximum:526.9
    Units:Watts per meter2
    Wind Speed
    Wind speed, averaged over timestep interval (30-minute resolution until February 7, 2013 and 15-minute resolution thereafter to December 31, 2015) (Source: https://sofia.usgs.gov/exchange/evapotrans/method.html)
    Range of values
    Minimum:0
    Maximum:17.54
    Units:Meters per second
    Wind Direction
    Wind direction, sampled every 15 minutes (every 30 minutes until February 7, 2013) (Source: https://sofia.usgs.gov/exchange/evapotrans/method.html)
    Range of values
    Minimum:-9.97
    Maximum:354.6
    Units:Degrees from True North
    Wind Speed Vector
    Wind speed vector, averaged over timestep interval (30-minute resolution until February 7, 2013 and 15-minute resolution thereafter to December 31, 2015) (Source: https://sofia.usgs.gov/exchange/evapotrans/method.html)
    Range of values
    Minimum:0
    Maximum:17.54
    Units:Meters per second
    Wind Direction Vector
    Wind direction vector, averaged over timestep interval (30-minute resolution until February 7, 2013 and 15-minute resolution thereafter to December 31, 2015) (Source: https://sofia.usgs.gov/exchange/evapotrans/method.html)
    Range of values
    Minimum:0
    Maximum:360
    Units:Degrees from True North
    Air Temperature
    Air temperature at about 4 meters depending on lake stage, averaged over timestep interval (30-minute resolution until February 7, 2013 and 15-minute resolution thereafter to December 31, 2015) (Source: https://sofia.usgs.gov/exchange/evapotrans/method.html)
    Range of values
    Minimum:5.556
    Maximum:37.09
    Units:degrees Celsius
    Air Temperature
    Air Temperature, Column N converted to degrees Kelvin (Source: https://sofia.usgs.gov/exchange/evapotrans/method.html)
    Range of values
    Minimum:278.706
    Maximum:310.24
    Units:Kelvin
    Relative Humidity
    Relative humidity, sampled every 15 minutes (Source: https://sofia.usgs.gov/exchange/evapotrans/method.html)
    Range of values
    Minimum:18.63
    Maximum:98.9
    Units:Percemt
    Battery Voltage
    Battery voltage, averaged over timestep interval (30-minute resolution until February 7, 2013 and 15-minute resolution thereafter to December 31, 2015) (Source: https://sofia.usgs.gov/exchange/evapotrans/method.html)
    Range of values
    Minimum:9.28
    Maximum:15.07
    Units:Volts
    Bottom Water Temperature
    Lake-bottom water temperature, averaged over timestep interval (30-minute resolution until February 7, 2013 and 15-minute resolution thereafter to December 31, 2015) (Source: https://sofia.usgs.gov/exchange/evapotrans/method.html)
    Range of values
    Minimum:14.78
    Maximum:31.36
    Units:degrees Celsius
    Bottom +2-ft Water Temperature
    Water temperature at 2 feet above lake bottom, averaged over timestep interval (30-minute resolution until February 7, 2013 and 15-minute resolution thereafter to December 31, 2015); Averaged between column Q and S for sample times starting March 30, 2015 0:00 due to instrument error (Source: https://sofia.usgs.gov/exchange/evapotrans/method.html)
    Range of values
    Minimum:14.65
    Maximum:31.77
    Units:degrees Celsius
    Bottom +4-ft Water Temperature
    Water temperature at 4 feet above lake bottom, averaged over timestep interval (30-minute resolution until February 7, 2013 and 15-minute resolution thereafter to December 31, 2015) (Source: https://sofia.usgs.gov/exchange/evapotrans/method.html)
    Range of values
    Minimum:14.56
    Maximum:31.93
    Units:degrees Celsius
    Bottom +6-ft Water Temperature
    Water temperature at 6 feet above lake bottom, averaged over timestep interval (30-minute resolution until February 7, 2013 and 15-minute resolution thereafter to December 31, 2015) (Source: https://sofia.usgs.gov/exchange/evapotrans/method.html)
    Range of values
    Minimum:14.52
    Maximum:31.82
    Units:degrees Celsius
    Bottom +8-ft Water Temperature
    Water temperature at 8 feet above lake bottom, averaged over timestep interval (30-minute resolution until February 7, 2013 and 15-minute resolution thereafter to December 31, 2015); Average between column T and V used for time steps starting March 30, 2015 0:00 due to instrument error (Source: https://sofia.usgs.gov/exchange/evapotrans/method.html)
    Range of values
    Minimum:14.61
    Maximum:33.25
    Units:degrees Celsius
    Bottom +10-ft Water Temperature
    Water temperature at 10 feet above lake bottom, averaged over timestep interval (30-minute resolution until February 7, 2013 and 15-minute resolution thereafter to December 31, 2015) (Source: https://sofia.usgs.gov/exchange/evapotrans/method.html)
    Range of values
    Minimum:14.67
    Maximum:36.17
    Units:degrees Celsius
    Bottom +12-ft Water Temperature
    Water temperature at 12 feet above lake bottom, averaged over timestep interval (30-minute resolution until February 7, 2013 and 15-minute resolution thereafter to December 31, 2015) (Source: https://sofia.usgs.gov/exchange/evapotrans/method.html)
    Range of values
    Minimum:6.751
    Maximum:38.69
    Units:degrees Celsius
    Bottom +14-ft Water Temperature
    Water temperature at 14 feet above lake bottom, averaged over timestep interval (30-minute resolution until February 7, 2013 and 15-minute resolution thereafter to December 31, 2015); Equals column W from March 30, 2015 due to instrument error (Source: https://sofia.usgs.gov/exchange/evapotrans/method.html)
    Range of values
    Minimum:14.56
    Maximum:38.82
    Units:degrees Celsius
    Water Surface Temperature Sensor 1
    Water surface temperature, Sensor 1, averaged over timestep interval (30-minute resolution until February 7, 2013 and 15-minute resolution thereafter to December 31, 2015) (Source: https://sofia.usgs.gov/exchange/evapotrans/method.html)
    Range of values
    Minimum:7.511
    Maximum:40.32
    Units:degrees Celsius
    Water Surface Temperature Sensor 2
    Water surface temperature, Sensor 2, averaged over timestep interval (30-minute resolution until February 7, 2013 and 15-minute resolution thereafter to December 31, 2015) (Source: https://sofia.usgs.gov/exchange/evapotrans/method.html)
    Range of values
    Minimum:5.899
    Maximum:60.36
    Units:degrees Celsius
    Averaged Water Surface Temperature
    Water surface temperature, computed as the average from Sensor 1 and 2; If data were missing, Column AC (SFWMD data) or AV (Stefan-Boltzmann Equation) used during period October 7, 2013 to February 14, 2014 and November 3, 2015 to December 16, 2015 depending on availability of SFWMD data (Source: https://sofia.usgs.gov/exchange/evapotrans/method.html)
    Range of values
    Minimum:12.48
    Maximum:40.335
    Units:degrees Celsius
    Averaged Water Surface Temperature
    Water Surface Temperature, Column AA converted to degrees Kelvin (Source: https://sofia.usgs.gov/exchange/evapotrans/method.html)
    Range of values
    Minimum:287.86
    Maximum:313.485
    Units:Kelvin
    Water Surface Temperature SFWMD IY025
    Water surface temperature from SFWMD Sensor DBKey IY025, degrees Celsius, used during period October 7, 2013 to February 14, 2014 when Column X and Y sensors were inoperative (Source: https://sofia.usgs.gov/exchange/evapotrans/method.html)
    Range of values
    Minimum:14.71
    Maximum:36.84
    Units:degrees Celsius
    Lake Stage (dW) SFWMD IY030
    Lake Stage sampled every 15 minutes, feet National Geodetic Vertical Datum of 1929 (NGDV29), using SFWMD data website DBHYDRO DBKey IY030 (Source: https://sofia.usgs.gov/exchange/evapotrans/method.html)
    Range of values
    Minimum:11.8
    Maximum:16.31
    Units:Feet
    Precipitation SFWMD 13081
    Daily Precipitation Total at LZ 40, inches, using SFWMD data website DBHYDRO DBKey 13081 (Source: Wacker & Shoemaker, 2015)
    Range of values
    Minimum:0
    Maximum:3.93
    Units:Inches
    Mean Water Temperature Tw
    Mean water temperature for submerged sensors (Source: https://sofia.usgs.gov/exchange/evapotrans/method.html)
    Range of values
    Minimum:14.766
    Maximum:31.559
    Units:degrees Celsius
    Change in Mean Water Temperature Δ Tw
    Change in mean water temperature from previous timestep (Source: https://sofia.usgs.gov/exchange/evapotrans/method.html)
    Range of values
    Minimum:-0.68186
    Maximum:0.6334
    Units:degrees Celsius
    Water Surface Temperature tws
    Water surface temperature as listed in column AA (Source: https://sofia.usgs.gov/exchange/evapotrans/method.html)
    Range of values
    Minimum:12.481
    Maximum:40.335
    Units:degrees Celsius
    Air Temperature ta
    Air temperature as listed in column R (Source: https://sofia.usgs.gov/exchange/evapotrans/method.html)
    Range of values
    Minimum:5.556
    Maximum:37.09
    Units:degrees Celsius
    Vapor Pressure at Water Surface ew
    Vapor pressure of water surface (Source: Lowe, 1977 http://dx.doi.org/10.1175/1520-0450(1977)016<0100:AAPFTC>2.0.CO;2; equation (2))
    Range of values
    Minimum:1671.52565
    Maximum:7506.310698
    Units:pascal
    Vapor Pressure of Saturated Air
    Vapor pressure of saturated air at about 4 meters depending on lake stage (Source: Lowe, 1977 http://dx.doi.org/10.1175/1520-0450(1977)016<0100:AAPFTC>2.0.CO;2; equation (2))
    Range of values
    Minimum:905.586953
    Maximum:6303.445672
    Units:pascal
    Vapor Pressure of Air ea
    Vapor pressure of air temperature at about 4 meters depending on lake stage (Source: Lowe, 1977 http://dx.doi.org/10.1175/1520-0450(1977)016<0100:AAPFTC>2.0.CO;2; equation (2))
    Range of values
    Minimum:335.2925987
    Maximum:3984.916324
    Units:pascal
    Psychrometer Constant γ
    Psychrometer constant (Source: https://sofia.usgs.gov/exchange/evapotrans/method.html)
    Range of values
    Minimum:65.78375
    Maximum:67.7358954
    Units:Kilopascals per degree Celsius
    Latent Heat of Vaporization λ
    Latent Heat of Vaporization (Source: https://sofia.usgs.gov/exchange/evapotrans/method.html)
    Range of values
    Minimum:2412.28215
    Maximum:2486.86006
    Units:Joules per gram
    CNR1 Albedo
    Albedo as measured by CNR1 sensor (Source: https://sofia.usgs.gov/exchange/evapotrans/method.html)
    Range of values
    Minimum:-0.4814974
    Maximum:3.99933819
    Units:Unitless
    CNR1 Rn
    Net Radiation as measured by CNR1 sensor (Source: https://sofia.usgs.gov/exchange/evapotrans/method.html)
    Range of values
    Minimum:-174.8
    Maximum:1094.4
    Units:Watts/meter2
    Dew Point
    Dew point at about 4 meters depending on lake stage (Source: https://sofia.usgs.gov/exchange/evapotrans/method.html)
    Range of values
    Minimum:-8.063364
    Maximum:28.92857
    Units:degrees Celsius
    Moist Air Density
    Moist air density at about 4 meters depending on lake stage (Source: https://sofia.usgs.gov/exchange/evapotrans/method.html)
    Range of values
    Minimum:1.138023
    Maximum:1.266788
    Units:grams per cubic meter
    Water Surface Temperature (Stefan-Boltzmann Equation)
    Water surface temperature computed on the basis of the Stefan-Boltzmann equation (Source: https://sofia.usgs.gov/exchange/evapotrans/method.html)
    Range of values
    Minimum:10.56939381
    Maximum:37.33189822
    Units:degrees Celsius
    Constants
    Explanation of constants used in calculations, and accompanying notes on equipment failures (Source: https://sofia.usgs.gov/exchange/evapotrans/method.html) Various constants
    Notes
    Constants used in calculations (Source: https://sofia.usgs.gov/exchange/evapotrans/method.html) Various constants
    Daily Evap
    Worksheet 2 (Source: https://sofia.usgs.gov/exchange/evapotrans/method.html)
    Row Labels
    Pivot Table Row Labels, Date of observation (Source: Worksheet 1, CR1000 Lake O_Data; Column A, Floor) MM/DD/YYYY
    Average of the Psychrometer Constant γ
    Daily average of the psychrometer constant, computed using pivot-table tool. (Source: Worksheet 1, CR1000 Lake O_Data; Column AM, Psychrometer Constant)
    Range of values
    Minimum:66.03
    Maximum:67.37
    Units:Kilopascals per degree Celsius
    Average of the Water Surface Temperature tws
    Daily average of the water surface temperature tws, computed using pivot-table tool. (Source: Worksheet 1, CR1000 Lake O_Data; Column AH, Averaged Water Surface Temperature)
    Range of values
    Minimum:13.81
    Maximum:32.38
    Units:degree Celsius
    Average of Air Temperature ta
    Daily average of air temperature, computed using pivot-table tool. (Source: Worksheet 1, CR1000 Lake O_Data; Column AI, Air Temperature ta)
    Range of values
    Minimum:9.58
    Maximum:31.16
    Units:degree Celsius
    Average of Vapor Pressure at Water Surface ew
    Daily average of vapor pressure of water surface ew, computed using pivot-table tool. (Source: Worksheet 1, CR1000 Lake O_Data; Column AJ, Vapor Pressure of Water Surface ew)
    Range of values
    Minimum:1684.22
    Maximum:4910.39
    Units:pascal
    Average of Vapor Pressure of Air ea
    Daily average of vapor pressure of air temperature ea, computed using pivot-table tool. (Source: Worksheet 1, CR1000 Lake O_Data; Column AL, Vapor Pressure of Air Temperature ea)
    Range of values
    Minimum:618.05
    Maximum:3433.07
    Units:pascal
    Average of CNR1 Rn
    Daily Average of CNR1 net radiation Rn, computed using pivot-table tool. (Source: Worksheet 1, CR1000 Lake O_Data; Column AQ, CNR1 Rn)
    Range of values
    Minimum:-59.67
    Maximum:276.91
    Units:Watts per meter2
    Average of Latent Heat of Vaporization λ
    Daily average of latent heat of vaporization λ, computed using pivot-table tool. (Source: Worksheet 1, CR1000 Lake O_Data; Column AO, Latent Heat of Vaporization λ)
    Range of values
    Minimum:2426.30
    Maximum:2477.35
    Units:Joules per gram
    Average of Shortwave Incoming
    Daily average of incoming shortwave radiation, computed using pivot-table tool. (Source: Worksheet 1, CR1000 Lake O_Data; Column D, Shortwave Incoming)
    Range of values
    Minimum:9.64
    Maximum:351.37
    Units:Watts per meter2
    Average of Shortwave Outgoing
    Daily average of outgoing shortwave radiation, computed using pivot-table tool. (Source: Worksheet 1, CR1000 Lake O_Data; Column E, Shortwave Outgoing)
    Range of values
    Minimum:1.82
    Maximum:34.18
    Units:Watts per meter2
    Average of Longwave Incoming
    Daily average of incoming longwave radiation, computed using pivot-table tool. (Source: Worksheet 1, CR1000 Lake O_Data; Column G, Longwave Incoming)
    Range of values
    Minimum:255.19
    Maximum:486.06
    Units:Watts per meter2
    Average of Longwave Outgoing
    Daily average of outgoing longwave radiation, computed using pivot-table tool. (Source: Worksheet 1, CR1000 Lake O_Data; Column H, Longwave Outgoing)
    Range of values
    Minimum:378.78
    Maximum:487.56
    Units:Watts per meter2
    Average of CNR1 Albedo
    Daily average of lake surface albedo, computed using pivot-table tool. (Source: Worksheet 1, CR1000 Lake O_Data; Column AP, CNR1 Albedo)
    Range of values
    Minimum:0.06
    Maximum:0.55
    Units:Unitless
    Average of Dew Point
    Daily average of dew point, computed using pivot-table tool. (Source: Worksheet 1, CR1000 Lake O_Data; Column As, Dew Point)
    Range of values
    Minimum:-0.26
    Maximum:26.37
    Units:degrees Celsius
    Average of Mean Water Temperature Tw
    Daily average of mean water temperature Tw, computed using pivot-table tool. (Source: Worksheet 1, CR1000 Lake O_Data; Column AF, Mean Water Temperature Tw)
    Range of values
    Minimum:14.87
    Maximum:31.27
    Units:degrees Celsius
    Sum of Precipitation SFWMD 13081
    Daily Precipitation Total, computed using pivot-table tool. (Source: Worksheet 1, CR1000 Lake O_Data; Column AE, Precipitation SFWMD 13081)
    Range of values
    Minimum:0.00
    Maximum:3.93
    Units:Inches
    Average of Lake Stage dW SFWMD IY030
    Daily average of lake stage dw, feet National Geodetic Vertical Datum of 1929 (NGDV29), computed using pivot-table tool. (Source: Worksheet 1, CR1000 Lake O_Data; Column AE, Lake Stage (dW) SFWMD IY030)
    Range of values
    Minimum:11.93
    Maximum:16.15
    Units:Feet
    Column S
    Unused (Source: N/A) None
    Time Start
    Daily start time, local time (Eastern Standard Time) without daylight savings applied (Source: Worksheet 1, CR1000 Lake O_Data; time stamp at start of day as listed in Column B, TIMESTAMP)
    Range of values
    Minimum:00:00:00 AM
    Maximum:00:00:00 AM
    Units:HH:MM
    Time End
    Daily end time, local time (Eastern Standard Time) without daylight savings applied (Source: Worksheet 1, CR1000 Lake O_Data; time stamp at end of day as listed in Column B, TIMESTAMP)
    Range of values
    Minimum:11:30:00 PM
    Maximum:11:45:00 PM
    Units:HH:MM
    Time Start
    Concatenation of date from column AF and local start time from column U (Eastern Standard Time) without daylight savings applied (Source: Worksheet 1, CR1000 Lake O_Data; time stamp at start of day as listed in Column B, TIMESTAMP)
    Range of values
    Minimum:11/15/12 0:00
    Maximum:12/31/15 0:00
    Units:MM/DD/YY HH:MM
    Time End
    Concatenation of date from column AF and local end time from column V (Eastern Standard Time) without daylight savings applied (Source: Worksheet 1, CR1000 Lake O_Data; time stamp at start of day as listed in Column B, TIMESTAMP)
    Range of values
    Minimum:11/15/12 23:30
    Maximum:12/31/15 23:45
    Units:MM/DD/YY HH:MM
    TStart
    Mean water temperature (Tstart) at daily start time, averaged over a time interval of 24 hours prior to start time, as looked-up from Worksheet 1 (Source: Worksheet 1, CR1000 Lake O_Data; Column AF, Mean Water Temperature Tw)
    Range of values
    Minimum:14.94
    Maximum:31.52
    Units:degrees Celsius
    TEnd
    Mean water temperature (Tend) at daily end time, averaged over a time interval of 24 hours prior to start time, as looked-up from Worksheet 1 (Source: Worksheet 1, CR1000 Lake O_Data; Column AF, Mean Water Temperature Tw)
    Range of values
    Minimum:14.93
    Maximum:31.54
    Units:degrees Celsius
    Qs
    Change in heat energy stored in the lake volume (Qs) (Source: https://sofia.usgs.gov/exchange/evapotrans/method.html)
    Range of values
    Minimum:-564.52
    Maximum:216.26
    Units:Watts per meter2
    Qap
    Rainfall energy flux, energy advected into the lake from precipitation (Source: https://sofia.usgs.gov/exchange/evapotrans/method.html)
    Range of values
    Minimum:-23.07
    Maximum:0.87
    Units:Watts per meter2
    Date
    Date (Source: Worksheet 2, Daily EVAP, Column A)
    Range of values
    Minimum:11/15/2012
    Maximum:12/31/2015
    Units:MM/DD/YYYY
    B
    Bowen Ratio (B) (Source: https://sofia.usgs.gov/exchange/evapotrans/method.html)
    Range of values
    Minimum:-116.13
    Maximum:18.81
    Units:Unitless
    B Filter
    Bowen ratio filter, if Bowen ratio value in column AD is between -0.65 and -1.3, Bowen ratio is not used and evaporation is computed by assuming complete conversion of net radiation to evaporation. (Source: Worksheet 2, Daily EVAP, Column AD; and https://sofia.usgs.gov/exchange/evapotrans/method.html)
    Range of values
    Minimum:-1.3
    Maximum:-0.65
    Units:Unitless
    B final
    Final Bowen ratio with filter applied. Blank when Bowen ratio is not used to calculate evaporation. (Source: Worksheet 2, Daily EVAP, Column AD; and https://sofia.usgs.gov/exchange/evapotrans/method.html)
    Range of values
    Minimum:-116.13
    Maximum:18.81
    Units:Unitless
    AE
    Available energy (Ae) computed as sum of net radiation plus energy advected into the lake from precipitation plus the change in stored heat energy (Source: https://sofia.usgs.gov/exchange/evapotrans/method.html)
    Range of values
    Minimum:-115.70
    Maximum:605.24
    Units:Watts per meter2
    Qnr
    Net solar radiation (Rn), as copied from column H (Source: Worksheet 2, Daily EVAP, Column H)
    Range of values
    Minimum:0.34
    Maximum:276.91
    Units:Watts per meter2
    E(Rn)
    Evaporation based on net radiation available for evaporation value in Column AJ if Bowen Ratio Filter is applied (E(Rn)) (Source: Worksheet 2, Daily EVAP, Column AJ)
    Range of values
    Minimum:0.01
    Maximum:9.81
    Units:millimeters per day
    Evaporation (E)
    Evaporation (E) (Source: https://sofia.usgs.gov/exchange/evapotrans/method.html)
    Range of values
    Minimum:0.00
    Maximum:17.23
    Units:millimeters per day

Who produced the data set?

  1. Who are the originators of the data set? (may include formal authors, digital compilers, and editors)
    • Michael A. Wacker and W. Barclay Shoemaker
  2. Who also contributed to the data set?
    Cooperative Funding with the South Florida Water Management District
  3. To whom should users address questions about the data?
    Michael A. Wacker
    USGS Caribbean-Florida Water Science Center
    7500 SW 36 St
    Davie, FL 33314
    USA

    954-377-5949 (voice)
    mwacker@usgs.gov

Why was the data set created?

This document describes 37.5 months of lake evaporation measurements made at USGS site name LZ40 beginning November 15, 2012 through December 31, 2015. This is the third data release for this site. The first data release covered the period November 15, 2012 through December 31, 2013. The second data release covered the period November 15, 2012 through December 31, 2014.

How was the data set created?

  1. What methods were used to collect the data?
    Method 0 of 1
    Type: Field
    Basic methodology from: Bowen, I. S., 1926, The ratio of heat losses by conduction and evaporation from any water surface, Phys. Rev., v. 27, p. 779-787.
  2. From what previous works were the data drawn?
    SFWMD DBHYDRO database (source 1 of 1)
    Browser, DBHYDRO, 2014, South Florida Water Management District: South Florida Water Management District, West Palm Beach, FL.

    Online Links:

    • www.sfwmd.gov/dbhydro

    Type_of_Source_Media: Time Series
    Source_Contribution:
    Daily rainfall total measured at LZ40, SFWMD DBkey: 13081 Lake stage levels (NGVD29) measured at LZ40 at 15 minute intervals, SFWMD DBkey IY030 Water surface temperature data measured at LZ40, SFWMD DBkey: IY025. Water surface temperature data used during the period October 7, 2013 to February 14, 2014 as needed.
  3. How were the data generated, processed, and modified?
    Date: 12-Oct-2016 (process 1 of 2)
    Site visits made approximately every six weeks to check instrumentation.
    Date: 31-Dec-2015 (process 2 of 2)
    Data downloaded via cellular modem weekly into spreadsheet. QA/QC made to data to ensure it is within expected values and no data is missing. Daily check of data via cellular modem to ensure it is operating within expected parameters.
  4. What similar or related data should the user be aware of?
    Anderson, E.R., 1954, Energy-budget Studies: U.S. Geological Survey Professional Paper 269, p. 71-119.

    Online Links:

    Other_Citation_Details:
    In Water-loss investigations: Lake Hefner Studies, technical report
    Bowen, I.S., 1926, The ratio of heat losses by conduction and evaporation from any water surface: Physics Review v.27.

    Other_Citation_Details: p. 779-787
    Fritschen, L.J. and Gay, L.W., 1979, Environmental Instrumentation: Springer-Verlag, New York.

    Other_Citation_Details: 209 pp.
    German, E.R., 2000, Regional Evaluation of Evapotranspiration in the Everglades: U.S. Geological Survey Water-Resources Investigation 00-4217.

    Other_Citation_Details: 48 p.
    Lowe, P.R., 1977, Title: An approximating polynomial for the computation of saturation vapor pressure.

    Online Links:

    Other_Citation_Details: p. 100-103
    Moreo, M.T. and Swancar, A., 2013, Evaporation from Lake Mead, Nevada and Arizona, March 2010 through February 2012: U.S. Geological Survey Scientific Investigations report 2013-5229.

    Online Links:

    Other_Citation_Details: 40 p.
    Shih, S.F., 1980, Water budget computation for a shallow lake – Lake Okeechobee, Florida: Water Resources Bulletin: JAWRA Journal of the American Water Resources Association 16: 724–727.

    Online Links:

    Sumner, D.M. and Belaineh, G., 2005, Evaporation, Precipitation, and Associated Salinity Changes at a Humid, Subtropical Estuary: Estuaries v. 28 no. 6.

    Other_Citation_Details: p. 844-855

How reliable are the data; what problems remain in the data set?

  1. How well have the observations been checked?
    All equipment was new and calibrated at time of installation. Surface temperature uses two independent sensors that are spot checked during site visits. Water surface temperature data (October 7, 2013-February 14, 2014) does not accurately represent water surface temperature as the buoy system that held the thermistors failed causing them to hang in the water column about six feet below the surface. The SFWMD water surface temperature data, when available, was used during the periods October 7, 2013 to November 12, 2013; December 4, 2013 to December 17, 2013; and January 14, 2014 until February 5, 2014. When the SFWMD water surface temperature data were not available, the Stefan Boltzmann Equation was used until the USGS buoy system was repaired on February 14, 2014. The Stefan-Boltzmann Equation was used again when the surface water temperature buoy system failed on November 3, 2015 due to wave action and was repaired 16 December 2015. In late 2015, the Bottom + 2 ft, + 8 ft, and + 14 ft temperature probes were reading higher than the other water temperature probes. The error had slowly increased since March 30, 2015 and all water temperature probes were replaced on 16 December 2015. The problem persisted and is thought to be related to the Campbell Scientific AM 16/32 Channel Relay Multiplexor which will be replaced in early 2016. The temperature data for the effected probes was averaged between the probes on either side.
  2. How accurate are the geographic locations?
  3. How accurate are the heights or depths?
  4. Where are the gaps in the data? What is missing?
    None
  5. How consistent are the relationships among the observations, including topology?
    None

How can someone get a copy of the data set?

Are there legal restrictions on access or use of the data?
Access_Constraints: None
Use_Constraints: None
  1. Who distributes the data set? (Distributor 1 of 1)
    Heather Henkel
    U.S. Geological Survey
    600 Fourth Street South
    St. Petersburg, FL 33701
    USA

    727-502-8028 (voice)
    727-502-8182 (FAX)
    hhenkel@usgs.gov
  2. What's the catalog number I need to order this data set?
  3. What legal disclaimers am I supposed to read?
    The data have no explicit or implied guarantees
  4. How can I download or order the data?

Who wrote the metadata?

Dates:
Last modified: 12-Jul-2016
Metadata author:
Michael A. Wacker
U.S. Geological Survey Caribbean-Florida Water Science Center
7500 SW 36 Street
St. Petersburg, Fl 33314
USA

954-377-5949 (voice)
727-502-8182 (FAX)
mwackers@usgs.gov
Metadata standard:
FGDC Biological Data Profile of the Content Standard for Digital Geospatial Metadata (FGDC-STD-001.1-1999)

Generated by mp version 2.9.33 on Tue Jul 12 09:59:52 2016

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Last updated: 23 December, 2016 @ 01:49 PM (KP)