Hi Viv,

The Raster Name Expressions parameter of the tool determines the file names. The default is to store them using this path:

VVV\YYYY\Depth_DDD\VVV_YYYYJJJ_DDD.img

Where VVV is the name of the variable (u, v, temperature, salinity), DDD is the depth, YYYY is the year, and JJJ is the day of the year (001 to 366). Are your rasters being stored with those names?

Calculating mean monthly currents is a little bit tricky. Eventually we hope to offer a tool in MGET to compute temporal averages; we have written some of the underlying code but have not had the time yet to complete it. Here are two other options:

1.    You can use the MGET tool named Create Climatological Rasters to obtain the same result. The normal use of this tool is to produce climatological averages from the entire time series—e.g. compute mean monthly current for 2009-2014 (that is the approximate temporal extent of the current HYCOM GLBa0.08 product). But by restricting this tool to utilize just one year of data, it will effectively produce means for just that year. For example, to create monthly means for 2012, use these parameters:

a.    HYCOM variable = your choice

b.    Statistic = Mean

c.    Climatology bin type = Monthly

d.    Output workspace = your choice

e.    Spatiotemporal extent options:

                                          i.    Spatial extent = your choice, or leave empty for global

                                         ii.    Minimum depth, Maximum depth = your choice, or leave empty for all depths

                                        iii.    Start date = 1/1/2012

                                       iv.    End date = 12/31/2012 (if in the United States; in Australia, you might need to enter 31/12/2012)

2.    You can use the ArcGIS tool named Mosaic To New Raster to combine multiple rasters into one. You have to manually select the rasters for each month (or write a script or Model Builder workflow to do it) and select MEAN for the Mosaic Operator. If this idea is attractive to you, you might want to modify the Raster Name Expressions of the MGET Create Rasters tool to generate rasters that include the month number, or store rasters for each month in a subdirectory. That might make it more convenient to quickly obtain the list of rasters for each month. See the documentation for the Raster Name Expressions parameter for the codes to use.

All the best,

Jason