What does And I miss you like the deserts miss the rain mean from Missing by Everything But the Girl?

The lyric "And I miss you like the deserts miss the rain" from the song "Missing" by Everything But the Girl is a simile that compares the feeling of missing someone to the way deserts long for rain. Deserts are typically dry and barren, so rain is a rare and precious occurrence for them. Similarly, the speaker in the song is expressing a deep sense of longing and emptiness in the absence of the person they miss. The simile conveys the intensity and significance of the speaker's feelings of loss and yearning.