Sounds plausible. Can you tell me what “bi-directional winds” are? Are there other examples of equally spaced “linear dunes” covering such large areas?
“Can you tell me what “bi-directional winds” are?”
Using North America as an example, you can watch the cyclonic weather systems generally move from west to east through the western and mid-western states. Elsewhere, you also see some of the cyclonic weather systems generally moving southeasterly out of Canada and into the United States before heading easterly. Other cyclone systems come out of the Atlantic ocean and circle clockwise over the Gulf of Mexico, northwards into the Midwest or along the Eastern coastline, before heading northeastwards back out into the Atlantic Ocean. These weather systems are steered in these directions by such forces as the Coriolis Force produced by the Earth’s rotation on its axis and the powerful Jetstream winds traveling between the thermal convergence and heat exchange of the Troposphere and the Stratosphere. When one of the cyclonic and anti-cyclonic weather systems pass overhead in the atmosphere, you can watch the wind direction move around the compass as different areas of the cyclonic winds push in constantly changing directions around the compass.
Bidirectional winds which persist for seasonal periods of time do not share that type of behavior seen within a typical cyclonic weather system. Instead, they are a special case of the trade winds. Trade winds came by their name because mariners learned that the winds tended to more reliably blow in one direction than others during a particular season, so the mariners could more often trust such little varying wind directions to propel their trader sailing ships to the intended destinations across the oceans. Bidirectional winds are a special case with respect to the trade winds, because the planetary level atmospheric circulation cells meet in a convergence zone and result in persistent wind direction in one direction or its opposite direction. The trade winds outside this convergence zone also change direction with the season, but they do so in a somewhat less linear fashion due to their liberation from the effects of being within the convergence zone where the winds of the planetary cells buffet and cancel each other except within two linear directions.