Extreme weather and climate-related adverse childhood experiences are a humanitarian crisis during the 21st century.

Extreme climate/weather events (ECEs) are potential sources of toxic stress for children, especially when they result in displacement, family separation, poverty, violence, or neglect. We define Environmentally driven Adverse Childhood Experiences (E-ACEs) as environmental stressors that can trigger trauma-related responses, amplify exposure to traditional ACEs, and increase the risk of long-term mental health problems. While direct neurobiological evidence on E-ACEs remains limited, research on traumatic and adverse childhood experiences (TRACEs) shows that early-life stress disrupts brain development, alters hypothalamic-pituitary-adrenal (HPA) axis regulation, and heightens vulnerability to mental illness. With the rising number of climate-displaced families and children, particularly in low- and middle-income countries (LMICs), ECEs pose an urgent humanitarian and public health challenge in the 21^st century. This perspective examines how repeated ECEs lead to childhood adversity and toxic stress, calling for climate-responsive mental health policies, strengthened family and community resilience, and trauma-informed approaches within disaster preparedness and response systems.