NOVA Season 42 Episode 20
NOVA
Season 42

Ep 20. Lethal Seas

  • TV-PG
  • May 13, 2015
  • 53 min
  • 7.4  (46)

Lethal Seas, a season 42 episode of the popular science documentary series NOVA, explores the alarming rise in ocean acidification caused by the emission of carbon dioxide into the atmosphere. The episode explores the impact of this phenomenon on marine biodiversity, examining how it disrupts the functioning of ocean ecosystems and threatens the survival of various species.

The episode opens with a description of the acidification process, which occurs when carbon dioxide from the atmosphere dissolves in the ocean and forms carbonic acid. This acidification causes a drop in pH levels, which in turn affects various chemical processes in the water, such as the formation of shells and skeletons by marine organisms. The episode also illustrates how human activities such as burning fossil fuels and deforestation have contributed significantly to the rise in carbon dioxide levels, leading to the acidification of the oceans.

The focus then shifts to the impact of ocean acidification on marine biodiversity. The episode features interviews with scientists who have been studying the effects of acidification on various marine organisms, such as oysters, clams, and mussels. One researcher explains how acidification affects the formation of shells in these mollusks by reducing the amount of carbonate ions in the water, which are crucial for shell formation. Other scientists describe how increased acidity levels affect the feeding and growth of various fish species, leading to reductions in their populations.

The documentary also explores the impact of acidification on coral reefs, one of the most diverse and productive ecosystems in the oceans. The episode describes how coral reefs provide a habitat for numerous species of fish and shellfish and also act as a buffer against storms and waves. However, acidification affects the ability of corals to secrete the calcium carbonate that forms their skeletons, leading to their dissolution. The episode shows how coral reefs worldwide are being affected by this phenomenon, with some scientists predicting their complete disappearance by the end of the century.

NOVA's Lethal Seas also highlights the larger implications of ocean acidification for human societies and economies. The episode features interviews with fishermen, seafood processors, and others whose livelihoods depend on the health of the oceans. The documentary describes how ocean acidification affects the abundance and quality of seafood, with some species becoming less palatable or less nutritious due to acidification. The episode also explores the economic impacts of acidification, which could lead to significant losses in revenue for fishing communities and seafood industries.

Throughout the episode, viewers witness the scientific community grappling with the immense challenges posed by ocean acidification. The documentary documents efforts to mitigate the effects of acidification, such as using selective breeding to produce mollusks and oysters tolerant of acidified waters. The episode also showcases research on how to reduce carbon dioxide emissions and reverse the trend of ocean acidification.

Overall, NOVA's Lethal Seas is a sobering and informative exploration of the devastating effects of ocean acidification on our oceans and the ecosystems they support. The documentary presents a compelling case for the need to address the issue of carbon dioxide emissions as a matter of urgency to protect the health and survival of marine life, human communities, and the planet as a whole.

Description
Watch NOVA - Lethal Seas (s42 e20) Online - Watch online anytime: Buy, Rent
NOVA, Season 42 Episode 20, is available to watch and stream on PBS. You can also buy, rent NOVA on demand at Amazon, Google Play, Apple TV online.
  • First Aired
    May 13, 2015
  • Content Rating
    TV-PG
  • Runtime
    53 min
  • Language
    English
  • IMDB Rating
    7.4  (46)