Partitioning value (100 tonnes/ha) of underlying shapefile to multiple features in same shapefile in areas that overlap using ArcGIS for Desktop?

Question

I have tried searching for an answer but can't think of a way to generalize my question to other scenarios. Looking for answers using ArcMAP 10.1.

I currently have two shapefiles. One contains different values for the quantity of dry matter (DM) per hectare (e.g. one patch of 100 metric tonnes (t) of dm per hectare, another of 50, another 70 and so on...). The other shapefile has 1 km pixels scattered over different locations, and each of these pixels has its own time and date stamp attached to it.

If two pixels overlap I want to distribute the percentage of that 100 t per hectare that between the two (or more) overlapping areas proportionatly to the area.

For example If two 1 ha pixels (ha to make it simple) have a 50% overlap, both features would have 25 t for the overlapping area (in reality we would now have 4 pixels); and if their were four 4 ha pixels with 50% overlap in the same space it will be 12.5 t (with 8 pixels)etc. (example picture below)

I would like to apply the above workflow in a model in ArcGIS 10.1 to a big dataset. I am happy to convert the shapefiles to rasters etc and have full access to the different tools.

Answer 1

Ended up solving this using a combination of the split feature by attribute tool by USGS, union tool, excel and clip.

1. Split up the shapefile from point 1 into single days using the split by attribute tool by USGS.
2. Use union tool to combine the single days from step 1 to create a new combined geodatabase. This will now have a column for every date that the shapefile overlaps indicated by a 1.
3. Import the geodatabase into excel, and then add together every nth column (indicated by 1 or -1) to determine the number of times it overlaps in a column (e.g. Column A)
4. Copy the rows from Column A data and FID reference to the step 2 created shapefile attribute table using join table
5. Clip the step 2 created attribute table to each of the days extracted from step 1. showing the daily daily emissions.