ESOP 1997 MNBBS Surface Dataset 1.0 General Description The Minnesota Bulletin Board Service (MNBBS) 1997 Surface Dataset is one of several surface datasets provided in the GEWEX Continental-Scale International Project (GCIP) Enhanced Seasonal Observing Period (ESOP) 1997. This dataset contains all the surface data from the Minnesota Bulletin Board Service stations. This surface dataset contains data from 101 stations in the ESOP 1997 time period (01 October 1996 through 31 May 1997) and for the ESOP 1997 domain. The ESOP 1997 domain is approximately 37N to 50N latitude and 85W to 99W longitude. This data is provided "asis". It has been translated into the JOSS QC format. No other changes have been made to the data. These data were not quality controlled by the University Corporation for Atmospheric Research/Joint Office for Science Support (UCAR/JOSS). 2.0 Detailed Data Description 2.0.1 MNBBS Algorithms The algorithms used to form the MNBBS surface data are not currently available. 2.1 Detailed Format Description The ESOP 1997 Surface Dataset 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. The table below details the data parameters in each record. Parameters Units (C Format) ---------- ---------------- Date of Observation UTC Nominal ('%-8s ') Time of Observation UTC Nominal ('%-5s ') Date of Observation UTC actual ('%-8s ') Time of Observation UTC actual ('%-5s ') Network Identifier Abbreviation of platform name ('%-10s ') Station Identifier Network Dependent ('%-15s ') Latitude Decimal degrees, South is negative ('%10.5f ') Longitude Decimal degrees, West is negative ('%11.5f ') Station Occurrence Unitless ('%3d ') Station Elevation Meters ('%7.2f ') Station Pressure, QC flag Hectopascals (mb) ('%7.2f %1c ') Reported Sea Level Pressure, QC flag Hectopascals (mb) ('%7.2f %1c ') Computed Sea Level Pressure, QC flag Hectopascals (mb) ('%7.2f %1c ') Dry Bulb Temperature, QC flag Celsius ('%7.2f %1c ') Dew Point, QC flag Celsius ('%7.2f %1c ') Wind Speed, QC flag m/s ('%7.2f %1c ') Wind Direction, QC flag Degrees ('%7.2f %1c ') Total Precipitation, QC flag mm ('%7.2f %1c ') Squall/Gust Indicator Code Value ('%1c ') Squall/Gust Value, QC flag m/s ('%7.2f %1c ') Present Weather, QC flag Code Value ('%4d %1c ') Visibility, QC flag Meters ('%8.2f %1c ') Ceiling Height (first layer) Hundreds of feet ('%7.2f ') Ceiling Flag (first layer), QC flag Code Value ('%2d %1c ') Cloud Amount (first layer), QC flag Code Value ('%2d %1c ') Ceiling Height (second layer) Hundreds of feet ('%7.2f ') Ceiling Flag (second layer), QC flag Code Value ('%2d %1c ') Cloud Amount (second layer), QC flag Code Value ('%2d %1c ') Ceiling Height (third layer) Hundreds of feet ('%7.2f ') Ceiling Flag (third layer), QC flag Code Value ('%2d %1c ') Cloud Amount (third layer), QC flag Code Value ('%2d %1c') The list of code values for the Present Weather is too large to reproduce in this document. Refer to WMO, 1988 for a complete list of Present Weather codes. The code values for the Squall/Gust Indicator are: Code Definition ---- ---------- blank No Squall or Gust S Squall G Gust The code values for the ceiling flag Indicator are: Code Definition ---- ---------- 0 None 1 Thin 2 Clear below 12,000 feet 3 Estimated 4 Measured 5 Indefinite 6 Balloon 7 Aircraft 8 Measured/Variable 9 Clear below 6,000 feet (AUTOB) 10 Estimated / Variable 11 Indefinite / Variable 12 12-14 reserved 15 Missing The code values for the Cloud Amount Indicator are: Code Definition ---- ---------- 0 0 ( or clear) 1 1 okta or less, but not zero or 1/10 or less, but not zero 2 2 oktas or 2/10-3/10 3 3 oktas or 4/10 4 4 oktas or 5/10 5 5 oktas or 6/10 6 6 oktas or 7/10-8/10 7 7 oktas or more, but no 8 oktas or 9/10 or more, but not 10/10 8 8 oktas or 10/10 (or overcast) 9 Sky obscured by fog and/or other meteorological phenomena 10 Sky partially obscured by fog and/or other meteorological phenomena 11 Scattered 12 Broken 13 13-14 Reserved 15 Cloud cover is indiscernible for reasons other than fog or other meteorological phenomena, or observation is not made. 2.2 Data Remarks 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). Precipitation is collected with varying frequencies (5min to hourly). Values given are cumulative, resetting at non-standard intervals. This data is provided "asis". It has been translated into the JOSS QC format. No other changes have been made to the data. 3.0 Quality Control Processing These data were not quality controlled by the University Corporation for Atmospheric Research/Joint Office for Science Support (UCAR/JOSS). 4.0 References Wallace, J.M., P.V. Hobbs, 1977: Atmospheric Science, Academic Press, 467 pp.