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NAVO MCSST

NAVO Multi-Channel Sea Surface Temperature (MCSST) data is in byte format. See the examples below for information on how to use NCL to read and plot this data.
mcsst_1.ncl: The NCL built-in function fbindirread can be used to read NAVO MCSST data. It's a simple process to expand this to float data and apply the constants that transform the data into actual SST's.

sst = new((/1024,2048/),"float")
sst = bytedata*xslope+yint: will convert the byte data to a float and calculate the true SST values.

See script for how lat/lon coordinate variables are created.

mcsst_2.ncl: Same script as example 1. Just demonstrates the non-interpolated data. I found that in areas with sparse data (e.g. the Caribbean), the interpolated values were greatly different from the observed values. If you plan to use this data for feature identification, verify your results with the observed values.
mcsst_3.ncl: Demonstrates zooming in on a subregion. We can turn off raster mode now, since the area is smaller.

For greater detail, we have changed to a higher resolution coastline by setting: mpDataBaseVersion = "Ncarg4_1".

When you plot a sub region, you need to turn off the cyclic point which is automatically added to each plot. This is done by setting: gsnAddCyclic = False

To zoom in on a region, you need to set the following resources:
mpMinLonF
mpMinLatF
mpMaxLonF
mpMaxLatF

mcsst_4.ncl: Used a Fortran shared object (composit.f) to create a composite image of a day and night pass. Because of the grid, a double loop of this size is extremely slow in an interpreted computer language like NCL. (IDL and MatLab would have similar issues). The external routine is simplistic, but significantly increases speed. You will want to use WRAPIT to compile the shared object.

    WRAPIT composit.f