请问连续干旱日和干旱间隔期怎么计算？

alextsui

As for the duration-related variable, the 90th percentile for a given mesh was used as a
threshold for determining a drought. That is, the soil moisture of selected drought months is
lower than that in 90% of months. Soil moisture below the threshold for consecutive months is
considered to be the same drought event. By counting the number of continuous months of
each drought, the average length of drought period in each mesh was calculated. The number
of months between two drought events is considered the reoccurring time period of drought.


上文中的连续干旱月和干旱间隔期怎么用ncl实现啊？