Lyric discussion by dk50b 

When trying to figure out what Black Francis was talking about, it's important to erase your current knowledge and put yourself back in the late 80s. There are two environmental events specifically mentioned that were top issues at that time.

The "10 million pounds of sludge from New York and New Jersey" refers to what became known as "Syringe Tide." Medical waste that was dumped illegally in the Atlantic and escaped from a landfill on Staten island. It then washed up all in various places around New York and New Jersey, particularly the Jersey Shore. A 50 mile slick made it way to NJ shore towns in the summers of 1997 and 1998, ruining both vacation seasons. Hypodermic needles, blood vials and discarded medicine was found among the debris.

As for the Creature in the Sky verse, it refers only to the hole in the ozone layer. That hole, which was found in the stratosphere over the Antarctic, was confirmed in 1985. There was widespread awareness of the hole and the effect if it spread to populated areas. The ozone layer absorbs UVB ultraviolet light from the sun. The cause was CFCs, which reacted with the sun to deplete the ozone. Without the layer, life on earth would be impossible. After the hole was discovered, many feared it could not be reversed, and that life on earth was under threat. A worldwide CFC ban was enacted in 1987. The Antarctic hole still develops every spring, and atmopsheric ozone levels aren't expected to return to pre-1980 levels till as late as 2075.

As for this verse also being a warning about climate change, back in the late 80s, the consensus on the threat posed by rising temperatures was just beginning to form. The possibility that carbon emissions could unnaturally raise the earth's temperatures was first discovered in 1896. It was not until 2001 that scientific debate on the existence of climate change and that it was caused by man ended. Knowledge of the threat posed by climate change in the late 80s was out there, but not widespread.

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