This is Beyond the Tattered Vale of the Stars by Mercurio Di Rivera.

A reading from the second age of Jarrella.

They followed the purification rituals precisely,

fasting three times a month and holding group prayers in the shallow seawater's

of a verdant cove with the orange sun setting on the horizon.

They lay halves submerged in the surf,

scrubbing the scales off their snouts with diamonds.

And as their skin tore, they pushed forward through their lacerations,

fleshed, rippling, backward, downward,

until their new bodies emerged.

In this way, they shed their transgressions.

They collected and piled hundreds of sloughed skins.

And after blessing the discarded flesh,

cleansing it of all sin, they feasted.

Ravenous from fasting, they tore into the mound of skins,

giving praise to the gods for the food they devoured.

And as they ate, they prayed for clean air.

The thick gases identified as excess carbon dioxide,

methane and nitrous oxide had appeared five years earlier.

Suffocating Mother Earth in a planetary haze,

blue skies turned sickly grey,

and temperatures rose steadily.

...