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new to ferret with an averaging / climatology question

Hi all.  I hope everyone is enjoying the new year.  I've just installed
ferret and have a question as to how to perform some data manipulations.  

I have 40 netcdf files from the ncar/ncep reanalysis, each is for an
extended winter.  Each file has one variable (uwnd, omega, etc) for 152
time values (daysofwinter) starting at nov1 and going foward to the next
year (ending at mar1 or mar2 depending on leap year).  They're indexed as
variablename.year1year2.nc.   So basically I have a 5-d data set (lat lon
level dayofwinter year) and I want to reduce it to  4-d (lat lon lev day
of winter).  What I want is the 40 year average for each point in
4-d space (the climatology).  As I've found there is some vagueness as to
the term climatology so I want to be specific: i want to take each point
and fix the lat lon level and day of winter, get that same value for the
same lat lon level dayowwinter from the other 39 data files and average
that specific point and do this for each point.  (sorry to be pedantic but
I'm trying to avoid confusion).  I then want to write this climatological
average as a file variablename.climatology.nc or something like that as a
unformatted binary.  The reason I want to ouput as unformatted binary
instead of keeping things as netcdf is I'm then going to take the
climatology file and use it as input for a program that calculates a
smooth climatology based on polynomial fitting.  Once this is done I'll
subtract the fitted curve from the original files to have the
anomalies.  (at some point I'll have to either convert the fitted raw
binary file to netcdf or dump all the existing files to binary so as to
subtract them unless someone knows of a way to work with the 2 formats

Sorry this is long but I wanted to be clear as to what I wanted to do and
where I'm headed.  If someone can help me out with this it would be very


Brent A. McDaniel

Dept of Earth and Atmospheric Sciences
Georgia Institute of Technology
Atlanta, Ga.  USA

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