Slowing ice melting from thermal radiation using sustainable, eco-friendly eggshells

Increased ice melting in the Arctic region has raised the atmospheric temperature, leading to more natural disasters, such as a growing number of wildfires in the western United States, which threaten human health and the environment. Safe and immediate solutions to prevent or at least slow ice melting will be critical in reducing natural disasters. Here, we investigated eco-friendly eggshells as thermal barriers to delay ice melting. By using a homemade environmental chamber, we determined that the thickness of materials is crucial in delaying water heating rather than their surface color. Moreover, multiple layers of crushed eggshells placed on top of iced water effectively reflected thermal radiation, delaying the time of ice melting by ~40% compared to the control without the layers. The eggshell layers also decreased the average water heating rate by ~30%, making them an effective thermal barrier. Since numerous eggshells are produced as waste worldwide, an eco-friendly, sustainable, and feasible thermal barrier can be prepared by repurposing them. In the future, deploying the eggshell layers in the Arctic region could contribute to slowing ice melting, which can cool the atmospheric temperature, reduce the number of natural disasters, such as wildfires, and eventually protect human health and the environment.