Plot temperature patterns from NC files

Question

Giulia on 21 Feb 2023

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https://au.mathworks.com/matlabcentral/answers/1916210-plot-temperature-patterns-from-nc-files

Answered: Ajay Gajulapally on 1 Mar 2023

I need to look at temperature patterns within a season (April till September). So far I have downloaded CMEMS NC files showing temperature data for the whole month of April (30 nc files total), as downloading it for the whole season takes enourmous time. Each nc files contains:

Variables:
    time  
           Size:       24x1
           Dimensions: time
           Datatype:   double
           Attributes:
                       axis          = 'T'
                       standard_name = 'time'
                       long_name     = 'Validity time'
                       calendar      = 'Gregorian'
                       units         = 'seconds since 1970-01-01T00:00:00Z'
    lat   
           Size:       1240x1
           Dimensions: lat
           Datatype:   single
           Attributes:
                       axis          = 'Y'
                       standard_name = 'latitude'
                       units         = 'degrees_north'
                       nav_model     = 'grid_T'
                       cell_methods  = 'longitude: mean'
                       long_name     = 'latitude'
    lon   
           Size:       958x1
           Dimensions: lon
           Datatype:   single
           Attributes:
                       axis          = 'X'
                       standard_name = 'longitude'
                       units         = 'degrees_east'
                       nav_model     = 'grid_T'
                       cell_methods  = 'latitude: mean'
                       long_name     = 'longitude'
    thetao
           Size:       958x1240x33x24
           Dimensions: lon,lat,depth,time
           Datatype:   int16
           Attributes:
                       _FillValue    = -32768
                       missing_value = -32768
                       scale_factor  = 0.001
                       add_offset    = 25
                       standard_name = 'sea_water_potential_temperature'
                       long_name     = 'Sea Water Potential Temperature'
                       units         = 'degrees_C'
                       valid_min     = -30000
                       valid_max     = 30000
    depth 
           Size:       33x1
           Dimensions: depth
           Datatype:   single
           Attributes:
                       axis          = 'Z'
                       standard_name = 'depth'
                       units         = 'm'
                       positive      = 'down'
                       long_name     = 'depth'

I think the evolution of temps at the mooring location through a year would be a good place to start. You could then look at e.g., weekly means for a transect through the mooring location from spring to autumn.

I am aiming to select a specific location within the lat and lon space, then observe temperature patterns (e.g. daily and weekly surface to bottom temperature difference, SSTs, bottom temps).

My question is how do I group all the temperature data for the month (or for the season later) into one file; and what plot function should I use to observe temperature patterns?

New to matlab so all help will be extremely appreciated!

Thanks a lot!!