The Sound of Life

Today while Sybil was having her daily swim it started to rain. The noise the rain made on my head and inside my skull seemed like the staccato beat of a drum played by an angry chimpanzee. Somehow I don't remember it being this loud thirty years ago. I assume rain is heavier today probably because the Earth is gaining mass or because of all of the heavy metals in the water. What else would explain the sound? Perhaps a physicist should weigh in. (Weigh being a word chosen at random that just happens to be apropos.)