How to process remote sensing data in matlab

I have downloaded remote sensing data and want to process the data. This is what i have done.'

 filename='windsat_remss_ovw_l3_20050126_v7.0.1.nc'

filename =

windsat_remss_ovw_l3_20050126_v7.0.1.nc

>> ncdisp(filename)
Source:
           C:\Program Files\MATLAB\MATLAB Production Server\R2015a\bin\windsat_remss_ovw_l3_20050126_v7.0.1.nc
Format:
           classic
Global Attributes:
           Conventions           = 'CF-1.6'
           title                 = 'Coriolis_WindSat_L3_OW_SST_ATM_REMSS'
           longname              = 'WindSat on Coriolis Level 3 Daily Gridded Ocean Surface Wind Vectors and Ancillary Fields from REMSS'
           references            = 'More information is available at www.remss.com/windsat'
           institution           = 'Remote Sensing Systems'
           contact               = '[e-mail]'
           netcdf_version_id     = '3.5.0'
           creation_date         = '2013-09-03'
           product_version       = 'v7.0.1'
           processing_level      = 'L3'
           creator_name          = 'Frank J. Wentz, PI DISCOVER Project, Remote Sensing Systems'
           history               = '9/03/2013: NetCDF files created from Remote Sensing Systems WindSat V7.0.1 data by Chelle Gentemann'
           platform              = 'Coriolis'
           sensor                = 'WindSat'
           source                = 'satellite'
           acknowledgement       = 'WindSat microwave radiometer data are processed by Remote Sensing Systems with funding from the NASA and Earth Science MEaSUREs Program and the NASA Earth Science Physical Oceanography Program.'
           start_date            = '2005-01-26'
           start_time            = '00:00:00 UTC'
           stop_date             = '2005-01-26'
           stop_time             = '09:42:00 UTC'
           latitude_resolution   = 0.25
           longitude_resolution  = 0.25
           southernmost_latitude = -89.875
           northernmost_latitude = 89.875
           westernmost_longitude = -179.875
           easternmost_longitude = 179.875
           file_quality_index    = 1
           comment               = 'Please see www.remss.com for more information.  Orbits separated into ascending and descending arrays.  The original numerical resolution of the data used to create this product was time: 0.1 hrs, sst: 0.15 deg Celcius, wind: 0.2 m/s, vapor: 0.3 kg/m2 (1 kg m-2 = 1 mm), cloud: 0.01 kg/m2, rain: 0.1 m'
Dimensions:
           time = 2
           lat  = 720
           lon  = 1440
Variables:
    lat                    
           Size:       720x1
           Dimensions: lat
           Datatype:   single
           Attributes:
                       long_name     = 'latitude'
                       standard_name = 'latitude'
                       units         = 'degrees_north'
                       valid_min     = -89.875
                       valid_max     = 89.875
    lon                    
           Size:       1440x1
           Dimensions: lon
           Datatype:   single
           Attributes:
                       long_name     = 'longitude'
                       standard_name = 'longitude'
                       units         = 'degrees_east'
                       valid_min     = -179.875
                       valid_max     = 179.875
    time                   
           Size:       2x1
           Dimensions: time
           Datatype:   int32
           Attributes:
                       long_name     = 'reference time of file'
                       standard_name = 'time'
                       units         = 'seconds since 1981-01-01 00:00:00'
    sea_surface_temperature
           Size:       1440x720x2
           Dimensions: lon,lat,time
           Datatype:   int8
           Attributes:
                       long_name     = 'sea surface temperature'
                       standard_name = 'sea_surface_temperature'
                       units         = 'Celsius'
                       _FillValue    = -128
                       add_offset    = 16.05
                       scale_factor  = 0.15
                       valid_min     = -127
                       valid_max     = 127
    dtime                  
           Size:       1440x720x2
           Dimensions: lon,lat,time
           Datatype:   int16
           Attributes:
                       long_name    = 'time difference from reference time'
                       units        = 'seconds'
                       _FillValue   = -32768
                       add_offset   = 0
                       scale_factor = 10
    wind_speed_lf          
           Size:       1440x720x2
           Dimensions: lon,lat,time
           Datatype:   int8
           Attributes:
                       long_name     = 'wind speed low frequency'
                       standard_name = 'wind_speed'
                       units         = 'm s-1'
                       _FillValue    = -128
                       add_offset    = 25.4
                       scale_factor  = 0.2
                       valid_min     = -127
                       valid_max     = 127
    wind_speed_mf          
           Size:       1440x720x2
           Dimensions: lon,lat,time
           Datatype:   int8
           Attributes:
                       long_name     = 'wind speed medium frequency'
                       standard_name = 'wind_speed'
                       units         = 'm s-1'
                       _FillValue    = -128
                       add_offset    = 25.4
                       scale_factor  = 0.2
                       valid_min     = -127
                       valid_max     = 127
    water_vapor            
           Size:       1440x720x2
           Dimensions: lon,lat,time
           Datatype:   int8
           Attributes:
                       long_name     = 'total columnar water vapor'
                       standard_name = 'atmosphere_mass_content_of_water_vapor'
                       units         = 'kg m-2'
                       _FillValue    = -128
                       add_offset    = 38.1
                       scale_factor  = 0.3
                       valid_min     = -127
                       valid_max     = 127
    cloud_liquid_water     
           Size:       1440x720x2
           Dimensions: lon,lat,time
           Datatype:   int8
           Attributes:
                       long_name     = 'cloud liquid water'
                       standard_name = 'atmosphere_mass_content_of_cloud_liquid_water'
                       units         = 'kg m-2'
                       _FillValue    = -128
                       add_offset    = 1.22
                       scale_factor  = 0.01
                       valid_min     = -127
                       valid_max     = 127
    rain_rate              
           Size:       1440x720x2
           Dimensions: lon,lat,time
           Datatype:   int8
           Attributes:
                       long_name     = 'rain rate'
                       standard_name = 'rainfall_rate'
                       units         = 'mm hr-1'
                       _FillValue    = -128
                       add_offset    = 12.7
                       scale_factor  = 0.1
                       valid_min     = -127
                       valid_max     = 127
    wind_speed_aw          
           Size:       1440x720x2
           Dimensions: lon,lat,time
           Datatype:   int8
           Attributes:
                       long_name     = 'wind speed all weather'
                       standard_name = 'wind_speed'
                       units         = 'm s-1'
                       _FillValue    = -128
                       add_offset    = 25.4
                       scale_factor  = 0.2
                       valid_min     = -127
                       valid_max     = 127
    wind_direction         
           Size:       1440x720x2
           Dimensions: lon,lat,time
           Datatype:   int8
           Attributes:
                       long_name     = 'wind direction'
                       standard_name = 'wind_to_direction'
                       units         = 'degrees'
                       _FillValue    = -128
                       add_offset    = 190.5
                       scale_factor  = 1.5
                       valid_min     = -127
                       valid_max     = 127

I want to know how to retrieve data from the variables such as " wind_speed_aw". What are the commands that i can use to get the data.

Thank You.

>>

[per isakson]

See: NetCDF Files, Network Common Data Form

[Kritesh Kumar]

I am still not able to get it, can anyone please show me how to do this

Answer 1

[KSSV]

clc; clear all ;
filename = 'windsat_remss_ovw_l3_20050126_v7.0.1.nc' ;

% read the variables

lon = ncread(filename,'lon') ;
lat = ncread(filename,'lat') ;
wind_speed_aw  = ncread(filename,' wind_speed_aw ') ;

surf(lon,lat,wins_speed_aw(:,:,1))
shading interp

Read about ncread. ncread is used to load/ read the data.

[Kritesh Kumar]

When i try the above codes it gives error. And this is the error it shows: {Error using surf (line 57) Z must be a matrix, not a scalar or vector.}

[KSSV]

There is typo error...I have corrected it now..

[Kritesh Kumar]

But still it gives error like {Error using surf (line 57) Data dimensions must agree.}

[Kritesh Kumar]

Please if you can help me out by showing the necessary steps

[KSSV]

clc; clear all ;
filename = 'windsat_remss_ovw_l3_20050126_v7.0.1.nc' ;
% read the variables
lon = ncread(filename,'lon') ;
lat = ncread(filename,'lat') ;
wind_speed_aw  = ncread(filename,' wind_speed_aw ') ;
surf(lon,lat,wins_speed_aw(:,:,1)) ; % if shows error transpose the matrix
shading interp