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).
Thank You