Hello, There is a task to derive a linear trend, for ex. 5 units/month for values located at the georeferenced global latidute-longitude grid. There are several grids corresponding to time steps, say for a month with 6 hour interval. Sure, one can create a loop and derive a trend value for each data point. Is there a better practice for this task to express it in a line or two or a dedicated package? Thank you -- Kind regards, Antonio Rodriges