tuulimustaa

Tuulimustaa is a Finnish term that translates literally to "wind stain" or "wind mark." It refers to a specific type of discoloration or fading that occurs on surfaces, particularly wood or painted surfaces, due to prolonged exposure to wind and weather. This phenomenon is not caused by direct sunlight, but rather by the abrasive action of wind-blown particles such as sand, dust, and ice crystals, combined with moisture.

Over time, these particles are repeatedly buffeted against the surface, gradually wearing away the top layers of paint or wood. This erosion can lead to a lighter, duller appearance in the areas most exposed to the prevailing winds. The effect is most noticeable on vertical surfaces like the sides of buildings, fences, or exposed furniture. The pattern of the tuulimustaa often follows the direction of the wind, creating a distinctive streaky or patchy discoloration. It is a natural process of weathering and is more pronounced in areas with strong prevailing winds and readily available abrasive particles.