Currently, I am working with surge characteristics of IWV and IWVF. My domain of study is, for now, 29 to 33N and -116 to -107W. Here is an example of the domain (plotted is precipitation on 19 Aug 1983).
For both IWV and IWVF a daily, domain-aggregated value was calculated from the daily-mean value of each pixel. This provided a daily value (1 June - 30 Sept) for each year of study (1980-2007). From this data the 95th, 90th, 80th, 70th and 50th percentile values were calculated for each day. This data provided the threshold from which events could be characterized for IWV and IWVF.
An event was first classified by one of five ways: The daily-aggregated value for each day was greater than or equal to the (1) 95th, (2) 90th, (3) 80th, (4) 70th or (5) 50th percentile for the specific given day. Events were further restricted to (A) two consecutive days or (B) three consecutive days of 1 through 5. Here are examples of events for IWVF and IWV, 3 consecutive days of equal to or greater than 90th percentile (2B), and a Hovmoller of precipitation for 1983:
Though the criteria for IWVF and IWV seem to be picking-up on some of the events displayed in the precipitation Hovmoller, it is clear that this classification is not yet perfected.As for tomorrow, further work will be done to refine this classification scheme. I will also begin work using EOF analysis to better understand IWVF and IWV patterns for July and August.
-jamie
It would be good to show a daily time series of IWV and IWVF instead of the figures 2/3 you have. You can always annotate figures to note the events of interest. Also, the homv plot, what is the domain over which you have averaged values? It is also worthwhile knowing what the "date" of the event corresponds to - is this the first day of 3+ consecutive days, or the last?
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