The text file "Wind speed.txt" contains hourly data and associated data-source flag from January 1, 1948, to September 30, 2016. The primary source of the data is the Argonne National Laboratory, Illinois (ANL). The data-source flag consist of a three-digit sequence in the form "xyz" that describe the origin and transformations of the data values. They indicate if the data are original or missing, the method that was used to fill the missing periods, and any other transformations of the data. Missing and apparently erroneous data values were replaced with adjusted values from nearby stations used as “backup”. As stated in Over and others (2010), temporal variations in the statistical properties of the data resulting from changes in measurement and data storage methodologies were adjusted to match the statistical properties resulting from the data collection procedures that have been in place since January 1, 1989. The adjustments were computed based on the regressions between the primary data series from ANL and the backup series using data obtained during common periods; the statistical properties of the regressions were used to assign estimated standard errors to values that were adjusted or filled from other series. Each hourly value is assigned a corresponding data source flag that indicates the source of the value and its transformations. As described in Over and others (2010), each flag is of the form "xyz" that allows the user to determine its source and the methods used to process the data. During the period 01/09/2016 hour 21 to 01/10/2016 hour 24 both ANL and the primary backup station at St. Charles, Illinois had missing wind speed data. The O'Hare International Airport (ORD) is used as an alternate backup station and the new regression equation and the corresponding new flag for wind speed are established using daily wind data from ORD for the period 10/01/2007 through 09/30/2016 following the guideline described in Over and others (2010). Reference Cited:
Over, T.M., Price, T.H., and Ishii, A.L., 2010, Development and analysis of a meteorological database, Argonne National Laboratory, Illinois: U.S. Geological Survey Open File Report 2010-1220, 67 p., http://pubs.usgs.gov/of/2010/1220/.