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Global Monsoon Onset and Retreat based on Precipitable Water and Wind. By: Dimitri Ververelli NASA Space Grant Symposium. Phoenix, AZ. April 18, 2009. Monsoon Study. Multi-Regional climate phenomenon Multiple definitions of onset Problem: No definition that allows for operational use
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Global Monsoon Onset and Retreat based on Precipitable Water and Wind By: Dimitri Ververelli NASA Space Grant Symposium. Phoenix, AZ. April 18, 2009
Monsoon Study • Multi-Regional climate phenomenon • Multiple definitions of onset • Problem: No definition that allows for operational use • Objective: Create an operational definition primarily based on Zeng and Lu (2004)
NCEP Data • From National Centers for Environmental Prediction (NCEP). • Based on satellite and surface observations. • 1° X 1° resolution, 6 hourly, global • Data period: April 2000 – March 2001. • Precipitable water (total water vapor in a vertical column) and 700 mb (10,000 ft) wind.
NPWI Based Onset • A normalized precipitable water index (NPWI) is calculated. • Onset and Retreat criterion is based on the Golden Ratio (0.618).