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Use the an_1x1.mv and/or the an_2x2.mv macros to compare the ECMWF analyses with the satellite images.
Task 6: Cross-sections
I think this task should move to the second look at analyses after 20/9?
The last task in this exercise is to look at cross-sections through Hurricane Nadine and the cut-off low.
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Q. Look at the PV field, how do the vertical structures of Nadine and the cut-off low differ? |
Changing forecast time
Cross-section data is only available every 24hrs.
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steps=[2012-09-22 00:00] |
Changing fields
A reduced number of fields is available for cross-sections: temperature (t), potential temperature (pt), relative humidity (r), potential vorticity (pv), vertical velocity (w), wind-speed (speed; sqrt(u*u+v*v)) and wind vectors (wind3).
Changing cross-section location
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#Cross section line [ South, West, North, East ] line = [30,-29,45,-15] |
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Remember that if the forecast time is changed, the storm centres will move and the cross-section line will need to be repositioned to follow specific features. This is not computed automatically, but must be changed by altering the coordinates above.
Exercise 2: The operational ECMWF HRES forecast
Exercise 1 looked at the synoptic development up to the 20-Sept-2012. This exercise looks at the ECMWF HRES forecast from this date and how the IFS model developed the interaction between Hurricane Nadine and the cut-off low.
Enter the folder 'HRES_forecast' in the 'openifs_2018' folder to begin.
Recap
The ECMWF operational deterministic forecast is called HRES. At the time of this case study, the model ran with a spectral resolution of T1279, equivalent to 16km grid spacing.
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Data is provided for a single 5 day forecast starting from 20th Sept 2012, as used in the paper by Pantillon et al. referred to at the start of this tutorial.
HRES data Data is provided at the same resolution as the operational model, in order to give the best representation of the Hurricane and cut-off low iterations. This may mean that some plotting will be slow.
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The parameters available in the analyses are also available in the forecast data.
Available plot types
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For this exercise, you will use the metview icons in the row labelled folder ' hres_rmse.mv : this plots the root-mean-square-error growth curves for the operational HRES forecast compared to the ECMWF analyses. hres_to_an_diff.mv : this plots a single parameter as a difference map between the operational HRES forecast and the ECMWF analysis. Use this to understand the forecast errors. |
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