DAILY MEAN TEMPERATURE FORMULAS AND TRUE DAILY MEAN

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DAILY MEAN TEMPERATURE FORMULAS AND TRUE DAILY
MEAN

• Glen Conner
• Kentucky State Climatologist Emeritus
• Cosponsored
• by
• Kentucky Climate Center
• and
• Climate Database Modernization Program

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Paired Observations Formulas

• Homonymous times were convenient
• F9 (h06h18)/2
• F17 (h07h19)/2
• F19 (h08h20)/2
• F21 (h09h21)/2
• F2 (h10h22)/2
• Note
• F is formula number
• H is hour of observation

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Triad Observation Formulas

• Three times per day were better
• F5 (h06h12h17)/3
• F6 (h06h12h19)/3
• F7 (h06h14h21)/3
• F8 (h06h14h22)/3
• F10 (h07h12h18)/3
• F11 (h07h13h21)/3
• F12 (h07h13h22)/3
• F14 (h07h14h20)/3
• F15 (h07h14h21)/3
• F16 (h07h15h23)/3
• F18 (h08h14h20)/3
• F20 (h09h15h21)/3

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Combination Observation Formulas

• Combinations were too complex
• F1 (h07h14h14h21h21h31)/6
• F3 (h03h07h11h15h19h23)/6
• F4 (h03h09h15h21)/4
• F13 (h07h14h21h21)/4

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Maximum-Minimum Formulas

• Maximum Minimum were most convenient
• F22 (xminxmax)/2
• F23 (xminh15)/2
• F24 (xminxmaxh08h20)/4
• F25 (xminxmaxh09h21)/4

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Sorted Annual Deviations from True Mean
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Proposal for Monograph

• No recent comprehensive study of these formulas
• No recent compilation or analysis of them
• Write a reference document for climate
  researchers to
• Describe each of 25 prescribed daily mean
  formulas
• Discuss how and why the formulas varied
• Explain the rationale for those variances
• Compare them to the true daily mean
• Identify correction factors for each formula
• Determine spatial variations in the corrections

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Conclusion

• CDMPs nineteenth century climate datasets
• Will become the baseline for climate studies
• Before sites were moved downtown
• On top of tall buildings
• Amid urbanization problems
• Before sites were moved to airports
• New baseline presents new problems of analysis
• Prescribed means formula problems
• Not encountered before
• A reference document is needed