I learned to model oil spill. When I looked the modeled results, I find that the same grid has “two different oil depths”. The two results are orders different (474mm V.S. 3.25mm). One value is seen according to click the grid; the other is seen by time series. You can see them in “Oil_1.jpg” and “Oil_2.jpg”. Why there are two values for one grid?
oil_1.jpg
oil_2.jpg
We have reproduced this issue. The reason for the different values is that what is displayed in the time series is dependent on the option selected for the particle tracks time history in the display options as attached. If you select “Current position”, the value will be the same between ViewPlan and the time series. However, if you select “Display to current time” in ViewPlan the value of the oil spill will then accumulate up to the current time step.
Dear support team, three remaining questions about drifter:(1) I still don’t understand the meaning of “accumulated up to the current time step” for “Display to current time”. How do they “add”? For example, for a given cell A: there are 5mm oil @ time 0 hour, 5mm @ time 1 hour, then the value will be “5+5”=10mm @time 1 hour? If it is true, when the time step decreases from one hour to half an hour, that is: 5mm oil @ time 0 hour, 5mm @ time 0.5 hour, 5mm @ time 1 hour, then the value will be “5+5+5”=15mm @time 1 hour. “10mm” is not the same as “15mm”, which is confusing.(2) I now change to “Current position of particle only”, though the value of the two cannot be the same (drifter_a.png). Yet the difference is small, compared to the orders of difference in my previous post.(3) When I use GetEFDC Fortran code to extract binary file of oil volume, which value will be exported (i.e., “Current position” or “Display to current time” which is accumulated up to the current time step)? If I only want to export the trajectory of oil particles (i.e., their x, y, z coordinate at every time step), what should I do in GetEFDC?