UNFCCC https://unfccc.int/topics/adaptation-and-resilience/the-big-picture/introduction-to-loss-and-damage explains this, but be aware of the extensive criticisms such as Article Values and Harms in Loss and Damage
and https://heinonline.org/HOL/Page?handle=hein.journals/cclr2019&div=8&g_sent=1 among many others.