[CTSARA] Frequency Shifting During a DX QSO?

[Jon Perelstein]

I was listening to a VK7 in Tasmania this morning (PSK-31 on 20 meters) and
his frequency kept shifting by about +/- 50Hz.  None of the other signals
on the band at that time were shifting in frequency.  All of the others
were shorter range (e.g., Western Europe, Florida).

When I QSO'd with him, he said that he noticed the shifting on my signal,
but had not experienced any frequency shifting on the other QSOs he had
participated in before talking with me.  He checked his waterfall and did
not see any frequency shifting on any other signals on the waterfall.  All
of his QSOs before me were shorter range for him (e.g., China and
Singapore).

Given where his beam was pointing, It's possible we were bouncing over the
North Pole.

Are there atmospheric conditions on long DX (especially over one of the
poles) that would cause the received frequency to bounce around a bit?

73s
Jon
WB2RYV