ewce09.azraftaohid.me/L4T1/EWCE 464/TUTORIAL 05/C01 - Class note.sync-conflict-20260714-050005-JDG742I.md

Geostatistical Analyst

Atmospheric ozone monitoring for California. Measured at multiple stations representing overall whole area's concentration.

Data Import

• Import all; though mostly be needed OzoeLeevel_O3_Sep06_3pm, and ca_outline
• ca_hillshade would help understand flat surface and where population mostly live
• Change OzoeLeevel_O3_Sep06_3pm symbology to: Quantities > Graduated colors; value = OZONE_LEVEL_VALUE (optional)

Geostatistical Analyst

• Ensure Geostatistical Analyst extension is checked
• Customize > Toolbox > Geostatistical Analyst
• Geostatistical Analyst > Geostatistical Wizard
• Geostatistical methods > Kriging
  • Dataset > Source Dataset: OzoeLeevel_O3_Sep06_3pm
  • Date Field: OZONE
  • Next
  • Kringing Type: Ordinary
  • Output Surface Type: Prediction
  • Keep default
  • Next
  • Keep default for now
  • Next
  • Keep default
  • Next
  • Understand each tab
  • Finish

Fix Extends

• Rename produced "Kringing" to "Default Kringing"
• Open properties > Extend:
  • Set the extent to: rectangular extent of ca_outline
• Open "Layers" properties:
  • Data Frame > Clip Options:
    • Clip to shape
    • Specify Shape: select Outline of Features to ca_outline

Explore > Hostogram

• Geostatistical Analyst > Explore Data > Histogram
• Set attribute to "OZONE_LEVEL_VALUE"
• Values are multiplied by 10 (automatic)
• Select by draging into the plot; check map
• It can be realized that ozone level is high on where population mostly live (i.e., flat or low elevation area)

Explore > QQPlot

• Geostatistical Analyst > Explore Data > Normal QQPlot (Quantile Quantile Plot)
• Set attribute to "OZONE_LEVEL_VALUE"
• Understand that data is not normally distributed ($y=x$)

Explore > Trend

• Geostatistical Analyst > Explore Data > Trend Analysis
• Set attribute to "OZONE_LEVEL_VALUE"
• Curve representating trend

Explore > Semivariogram

• Geostatistical Analyst > Explore Data > Semivariogram/Covariance Cloud
• Set attribute to "OZONE_LEVEL_VALUE"

Mapping Ozone Conc.

• Geostatistical Analyst > Geostatistical Wizard > Kringing
  • Kringing Type: Ordinary
  • Set order of trend removal to second
  • Next
  • Keep default
  • Next:
    • Under View Settings, set search direction to true
    • May reduce lag size (e.g., to $15000$)
    • Under Model #1, set Anistropy to true
  • Next:
    • Under "Search Neighborhood", may change sector type, copy from variogram > angle (e.g., to 90)
    • Ellipse may be moved by clicking on points on the map, or
    • Under "Predicted Value", may change X (e.g., to 66000), Y (-220000)
  • Next:
    • Observe "Normal QQPlot"
  • Finish
• Fix extend

Prediction Standard Error

• Right click into "Kringing"
• Select "Change Output to Prediction Standard Error"
• Compare with <...>
• Revert

Validation Comparison

• Right click into "Kringing"
• Open "Compare"
• Compare with "Default Kringing"