Added Heating ExperimentObjectives
What am I expected to do?
Perform the added heating experiment
The instructions are here
Perform the control experiment
Following a similar procedure as the added heating experiment, perform the control experiment.
A control expeirment means that everything is exactly the same except the thing you changed, in this case, the added heating. This means the two can be cleanly compared to see the impact of added heating.
Use the script called
addheat.control.csh located in
Make a plot showing the impact of the added heating
The plot should show the same information as the one Dr. Swenson showed us.
Handling the output
You will nead to use the history files, not postprocessed time series files for this. The postprocessing only handles monthly data and requires full years to be complete. The heating output is 6 hourly located in the
h2 history files and the dynamical variables (e.g. U,V,Z) are daily and are located in the
h1 history files.
As an example, I provide code for reading the
h1 history files from my added heating experiment below:
path='/glade/scratch/kpegion/archive/' exp_ah='addheat2' fstub_h1='.cam.h1.*.nc' ds_ah_h1=xr.open_mfdataset(path+exp_ah+'/atm/hist/'+exp_ah+fstub_h1, combine='nested',concat_dim='time')
What to plot
Make a plot consistent with Dr. Swenson plot. His plot shows the difference between added heating and control averaged over the 3-months of the run for total heating (filled contours), added heating (black contours) and 200 hPa geopotential height as a representation of the changes in the storm track (blue and red contours). Below are some hints on how to get and calculate these 3 quanitites from the model output.
To calculate the total heating averaged from 850hPa to 50hPa for the added heating experiment.
- Get the total heating by adding the heating variables together. These variables are
- Select the 850hPa to 50hPa levels and average over those levels.
- Calculate the mean over the 3-months of the experiment by averaging the data in time.
Do the same for the control experiment, noting that
Nudge_T (the added heating) does not exist in the control experiment.
Now, calculate the difference between the two experiments as Added Heating minus control.
Check your units and convert them to K/day
200 hPa Geopotential Height Differences
To calculate the differences in the 200 hPa geopotential height between the two experiments,
- Use the
Z3variable for Geopotential Height
- Select the lev=200
- Take the average over the 3-months
- Difference the two experiments as added heating minus control
From the added heating experiment only, calculate the 850hPa-50hPa average of the
Nudge_T variable and average over the 3-months of the experiment.
How to turn it in?
You may send me the figure itself or the location of your figure.
Make sure it is properly labelled (units, lats/lons, contours, title) and is a
single figure (this will involve using
contourf once and
contour twice (maybe more times if you are matching Dr. Swenson’s colors exactly).
When is it Due?