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AREPGURME

Section 10 Exercise

Exercise

Interpreting Radiosondes Mixing height calculator Using HYSPLIT Flowchart of good/poor air quality

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AREPGURME

Section 10 Exercise

Exercise – Interpreting Radiosondes (1 of 5)

Instructions• Determine the following for each day

– 850-mb temperature– Inversions– Afternoon mixing height based on morning temperature sounding

and the given forecast maximum temperature– Afternoon mixing height on afternoon sounding

• Answer the following questions– Did the mixing height estimate from the morning sounding match

the mixing height determined from the afternoon sounding?– How would you expect morning and afternoon air quality

concentrations to compare based on vertical mixing alone?– How would air quality concentrations compare between the days?

Time: 15 minutes

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AREPGURME

Section 10 Exercise

Exercise – Interpreting Radiosondes (2 of 5)

Day 1 morning sounding

– forecasted maximum temperature: 33 °C

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AREPGURME

Section 10 Exercise

Exercise – Interpreting Radiosondes (3 of 5)

Day 1 afternoon sounding

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AREPGURME

Section 10 Exercise

Exercise – Interpreting Radiosondes (4 of 5)

Day 2 morning sounding

– forecasted maximum temperature: 31 °C

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AREPGURME

Section 10 Exercise

Mixing height calculator

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AREPGURME

Section 10 Exercise

Exercise – Interpreting Radiosondes (5 of 5)

Day 1 afternoon sounding

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AREPGURME

Section 10 Exercise

Exercise – Using HYSPLIT

Instructions: Run backward HYSPLIT trajectories at various levels to determine possible transport sources. Experiment with the different options of the program (i.e., vertical motion scheme).

Time: 15 minutes

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AREPGURME

Section 10 Exercise

Exercise – Flowchart

Instructions: Fill in a flowchart to identify conditions for both good and bad air quality.

Time: 15 minutes

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AREPGURME

Section 10 Exercise

Exercise – Flowchart Good AQUpper-level pattern

Vertical motion

Stability Surface pressure pattern

Inversion strength

Sky cover

Amount of photochemistry

Wind strength

Amount of horizontal dispersion

Amount of vertical mixing

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AREPGURME

Section 10 Exercise

Exercise – Flowchart Poor AQUpper-level pattern

Vertical motion

Stability Surface pressure pattern

Inversion strength

Sky cover

Amount of photochemistry

Wind strength

Amount of horizontal dispersion

Amount of vertical mixing

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AREPGURME

Section 10 Exercise

Exercise – Map Discussion

Instructions: Have a local forecaster lead a map discussion, focusing on the features discussed in this section.

Time: 45 minutes