Ɛ thi̱äk kɛ lat kä min lot pe̱k yi̱ëërɛ(sea level) kɛ datum mi̱ WGS 84,ɛn ɛlli̱pthi̱öd gua̱a̱th in ca ti̱ ŋuan lat kɛɛ luɔtdiɛn kä Grabi̱tational Wi̱cmuɔ̱ɔ̱n model 2008(EGM2008),ɛla̱t kɛ jɛ kɛɛ i̱thperi̱kal Ɣa̱rmönikni̱.