Karachi Seashells: Monsoon Mystery Unveiled

Karachi's coastline has once again been inundated with millions of seashells, a recurring spectacle occurring around June each year. This phenomenon, locally termed 'aokar,' is primarily driven by the arrival of the southwest monsoon. Scientific research explains that strong monsoon winds trigger ocean upwelling, bringing cold, oxygen-depleted water from the deep sea to the surface.

This upwelling process proves fatal for bottom-dwelling shellfish, such as clams, which cannot escape the rapidly changing conditions. Powerful monsoon waves then carry their empty shells onto the shores. Marine experts identify June and July as the peak season for this event, though pollution and rising sea surface temperatures, including a recent marine heatwave advisory for the Arabian Sea, may be contributing to increased shell volumes observed in 2026.

Beyond a natural wonder, the collected seashells form a source of livelihood for coastal communities, being transformed into various handicrafts like jewelry and decorative items. Researchers are also exploring their industrial potential, finding that seashells can be converted into bio-calcium carbonate to enhance the properties of common plastics.