Portugal Solar Halo

A 22-degree solar halo above Cristo-Rei (Christ the King) monument overlooking Lisbon, Portugal. As noted by the photographer “When sunlight interacts with ice crystals in high-level clouds, 22° halos may result. Orient these crystals in every direction across the sky, and you’ll see a beautiful light ring centered on the Sun with a 22° radius. That is about the width of your outstretched hand, from thumb to pinky, held at arm’s length. It helps to block the Sun with your hand or a foreground object. Sunglasses will cut down on glare and enhance any display colors. Halos can occur any time of the day and last from minutes to hours. The most striking and colorful displays occur when near-invisible “stealth” cirrostratus move in just before a warm front.”