This assignment consists of two parts. Part I is a simple install and practice and Part II will be a data exercise involving sea surface temperatures.

Upload Part I here

Procedure:

Part I:

1. Download and install the panoply viewer.
   
   
2. Login with some shell to your ACISS account:
   
   
   a) mkdir nc
   
   b) cd nc
   
   c) cp ~dkmatter/nc/nc_create.py .
   
   d) edit (using any editor) nc_create.py and change nx and ny to 600 and 1200 (gedit is a simple text edit program on ACISS)
   
   e) module load python
   
   f) python nc_create.py produces an output file called xy.nc
   
   g) launch panoply and view the file - it should look like this
   
   
   
   h) hit the array tab and look at the array number population - what do you think the command
   
   arange(nx:ny) in the program nc_create.py does? Include this answer in your write up.
   
   i) now go back and edit the program and set nx=ny=12 and run the program and display in panoply the array value.
   
   j) Cut (Control C) and Paste out the array values into an Excel SpreadSheet and include that in your write up. This will prove useful later when you want to extract certain array ranges out of the netCDF array
   
   k) if you have successfully displayed the array as a color map you are ready to move onto part 2
   
   
   Upload Part 2 here
   
   Procedure:
   
   
   • From aciss, cp ~dkmatter/nc/sst.nc to grab the main data file
   • Load this into the Panoply viewer
   • The initial view will be for one slice in the data and there are 24 slices, each a month long, that you can get from the drop down menu associated with the viewer.
   
   
   
3. Exercises to do: (for all of these exercises you will be wanting to cut and paste the array values into your analysis program. This is similar to what you did for the first assignment. You have a temperature for latitude and longtitude.
   
   
   1. Define 4 regions that correspond to
   a) the equatorial pacific ocean
   b) the Gulf of Mexico
   c) The Nothern Indian Ocean
   d) The southern California Coast
   
   
   
   Determine the rate of temperature increase from March to September in these 4 regions and plot all 4 of these temperature gradients on one plot
   
   2. Now do the same thing for September to March (cooling season) and comment on any thing that you might notice.
   
   3. This last part involves a lot of array operations.
   
   Select the month of July. For the northern hemisphere, between latitudes of 0 and 40 degrees, find a 1000 km East West line (e.g. a latitude) that shows the maximum temperature gradient along that 1000 km and report its value and indicate the location.
   
   Now do the same exercise for a line of longtitude (again 1000 km long). Of course these are arcs, not lines.
   
   Now put your science hat on and compare these two gradients and make an argument about why they are different.
   
   Extra Credit: See if you can figure out how to actually make an animated time series of the individual time slices in Panoply. I am pretty sure that you can, but I haven't figured it out yet ...