Sea Ice Fractures in a Warming World: Projected Changes in Leads and Ridges

Linear Kinematic Features (LKFs) --- narrow bands of deformation forming fractures (leads) and ridges in sea ice --- are crucial to the polar climate system, significantly influencing heat, moisture, and momentum exchange between the ocean and atmosphere. Despite their importance, their response to warming remains poorly understood due to observational and modeling challenges. Using high-resolution (4.5 km) FESOM2 simulations, we project substantial LKF changes from 1986 to 2100 under SSP585 (+4°C global warming). The most dramatic transformations begin in the 2020s, with increased winter LKF occurrence. By the late 21st century, winter LKFs increasingly resembles today’s summer conditions, driven by thinning ice and intensified ocean currents and winds. These changes signal a fundamental shift in the Arctic system, with dual implications: leads may enhance navigability, while ridges increase shipping risks. This study advances understanding of sea ice dynamics and highlights the need for integrated strategies to address emerging Arctic challenges.