Changes in the Spatial Distribution of Changes in the Spatial Distribution of Ozone in Texas fromOzone in Texas from

Weekdays to WeekendsWeekdays to Weekends

Gookyoung HeoGookyoung HeoEnvironmental & Water ResourcesEnvironmental & Water Resources

Engineering Program, Department of Civil Engineering, Engineering Program, Department of Civil Engineering, University of Texas at AustinUniversity of Texas at Austin

Air Quality & GISAir Quality & GIS Complex and Comprehensive DataComplex and Comprehensive Data Frequent relocation of monitoring stationsFrequent relocation of monitoring stations Frequent irregular short-term or long-term Frequent irregular short-term or long-term

missing datamissing data Spatial Distribution (Characteristics of Air Spatial Distribution (Characteristics of Air

Pollution)Pollution) This Study: Weekday-Weekend Differences ofThis Study: Weekday-Weekend Differences of Ozone Distribution (With Ozone Distribution (With Application of Arc Hydro)Application of Arc Hydro)

DATADATA EPA-AIRSEPA-AIRS (Big Raw Data Files: X00 MB) (Big Raw Data Files: X00 MB) TNRISTNRIS Texas State, Counties (Shape files)Texas State, Counties (Shape files) Time Series Data (Processed)Time Series Data (Processed) *ArcGIS, ArcHydro-Compatible Format*ArcGIS, ArcHydro-Compatible Format Spatial and Temporal Data (Location, TimSpatial and Temporal Data (Location, Tim

e)e)

Extracting from the Raw Extracting from the Raw DataData

TSDateTimeTSDateTime Julian Day, Specific Format Julian Day, Specific Format (MM/DD/YYYY HH:mm:ss): DateTime(MM/DD/YYYY HH:mm:ss): DateTime EX) August 1, 1998, 8 AM.EX) August 1, 1998, 8 AM. 08/01/1998 08:00:0008/01/1998 08:00:00 Make Data in This Format (How?)Make Data in This Format (How?)

TSDateTimeTSDateTime Julian Day, Specific Format Julian Day, Specific Format (MM/DD/YYYY HH:mm:ss): DateTime(MM/DD/YYYY HH:mm:ss): DateTime EX) August 1, 1998, 8 AM.EX) August 1, 1998, 8 AM. 08/01/1998 08:00:0008/01/1998 08:00:00 Make Data in This Format (How?)Make Data in This Format (How?)

TSType (Day of Week)TSType (Day of Week)

TSType (ID for the subgroups)TSType (ID for the subgroups) Weekdays, Weekends (SUN, SAT)Weekdays, Weekends (SUN, SAT)

TSType (Day of Week)TSType (Day of Week)

TSType (ID for the subgroups)TSType (ID for the subgroups) Weekdays, Weekends (SUN, SAT)Weekdays, Weekends (SUN, SAT)

Year,Month,Day,Hour

Julian Day from a Starting Day

Day of Week (Accumulated Julian Day/7)

: If the starting day is Monday,

MOD (Accumulated Julian Day, 7)= ?MOD(Monday, 7) =1MOD(Sunday, 7) =0

TSType (Day of Week)

TSType (Day of Week)TSType (Day of Week)

Adding the Time Series Adding the Time Series Data and Monitoring Data and Monitoring

Station DataStation Data

Get the Spatial Get the Spatial InformationInformation

Joining

Displaying the Joined Displaying the Joined DataData

Future WorkFuture Work Removing Flaws in the Prepared DataRemoving Flaws in the Prepared Data Spatial and Temporal Analysis of Spatial and Temporal Analysis of

Ozone Data of Texas during the Peak Ozone Data of Texas during the Peak Ozone Months (Summer)Ozone Months (Summer)

Spatial Interpolation (If appropriate)Spatial Interpolation (If appropriate) Weekday-Weekend DifferencesWeekday-Weekend Differences

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