Is the windward or leeward side steeper on a sand dune?

The windward side of a sand dune is generally gentler and more gradual, while the leeward side is steeper. This steep slope on the leeward side, often referred to as the slip face, forms as sand is deposited on the windward side and then cascades down the leeward side due to gravity. As a result, the leeward side typically has a more pronounced angle of repose compared to the windward side.