What does "奥观海" mean?

美国总统奥巴马（Barack Obama）。在一次访华时受中方赠送书法“观海听涛”一幅，大家都觉得”听涛“另有内涵，因而奥巴马得名奥观海.

ENUS President Barack Obama. During a visit to China, he was presented with a piece of calligraphy 'Guān Hǎi Tīng Tāo' (Watching the Sea and Listening to the Waves) by the Chinese side. Everyone felt that 'tīng tāo' (listening to the waves) had another meaning, so Obama was named 'Ào Guān Hǎi'.