Rainfall units conversion from depth to rate/intensity

Question

Given 6-hour rainfal data with units in meters(m), how can one convert the 6-hourly rainfall depth in meters(m) to 1-hourly rainfall intensity or rate in kg/m^2/s?
Below is a sample data value to convert.
rainfall depth (m)= 0.0014061

This is what I have tried but not sure it is correct:
To convert the 6h value to the hourly rate, I applied a multiplicative factor:
factor=0.046296296 kg/m2/s

based on the reasoning that the equivalent to:
m (in 6 hours) to mm/s = 1000/21600 (i.e. 0.0462963)

How do I use the multiplicative factor (0.046296296 kg/m2/s) to convert 6-hour rainfall depth to hourly?
Maybe I am thinking too much here.
Any thoughts?
Thank you.

Fabiola · Accepted Answer

Your 6-hour rainfall data represent the depth of water fallen in 6 hours. In order to have the average rainfall intensity in m/s corresponding to that interval of time, you have to divide the rainfall depth for the number of seconds in the time interval or for mm/s you multiply for 1000/21600. If you want the intensity in m/h you divide for 6 hours.
You have only the cumulative rainfall in 6 hours so you can estimate the intensity dividing equally the volume of rainfall over the 6 hours. The information remains the same. The real intensity was not constant over the 6 hours, obviously. You cannot, therefore, obtain the real 1-hour rainfall depth for each hours from 6-hours rainfall depth but only an average value that assumes it constant in each hour. If you have the measured 1-hour rainfall depth data in meter and you calculate the intensity in m/s from that data the results will be different.
I hope to have correctly understood your doubts and that this made things clearer.

Rainfall units conversion from depth to rate/intensity

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