Continents don't move with time in AACGM maps

[johncoxon]

I am currently experimenting with plotting AMPERE data on a plotUtils.mapObj and it's going pretty well, but I think I've uncovered a bug. When I plot in AACGM coordinates, the continents don't rotate underneath the data, which I think they should do – in the below code I would expect the continents to be rotated 180° from each other, and they are clearly not (see picture).

plt.close('all')
fig, ax = plt.subplots(2)
aacgm_map1 = plotUtils.mapObj(datetime = dt.datetime(2012,12,3), boundinglat = 60, coords = 'mag', altitude = 780, ax = ax[0])
aacgm_map2 = plotUtils.mapObj(datetime = dt.datetime(2012,12,3,12), boundinglat = 60, coords = 'mag', altitude = 780, ax = ax[1])

[MuhammadVT]

Hi,

If you want to rotate the continents while setting coords = "mag", you can do so by changing lon_0 argument. If you want the map to be in coords = "mlt", then it will rotate automatically based on the datetime you entered.

Hope this help.

Muhammad

On Wed, Jul 4, 2018, 5:27 AM johncoxon notifications@github.com wrote:

I am currently experimenting with plotting AMPERE data on a plotUtils.mapObj and it's going pretty well, but I think I've uncovered a bug. When I plot in AACGM coordinates, the continents don't rotate underneath the data, which I think they should do – in the below code I would expect the continents to be rotated 180° from each other, and they are clearly not (see picture).

plt.close('all') fig, ax = plt.subplots(2) aacgm_map1 = plotUtils.mapObj(datetime = dt.datetime(2012,12,3), boundinglat = 60, coords = 'mag', altitude = 780, ax = ax[0]) aacgm_map2 = plotUtils.mapObj(datetime = dt.datetime(2012,12,3,12), boundinglat = 60, coords = 'mag', altitude = 780, ax = ax[1])

[image: continents-not-rotating-in-mapobj] https://user-images.githubusercontent.com/1693743/42268917-abeae208-7f74-11e8-8717-5f4241b40964.png

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[johncoxon]

Thanks, that was very helpful! I hadn't appreciated that longitude in AACGM is defined by where the geomagnetic pole resides, rather than by where the Sun is. I presume setting coords = MLT keep everything in AACGM but orient the continents by MLT rather than by longitude?

It might be useful to add some examples of maps using coords= "mlt" to the Jupyter Notebooks that demonstrate use of the mapObj object, so that future users don't trip up in the same way, but I will mark this ticket closed.