Effects on the ocean

Young animals

  • Oyters along the Oregon/Washington coastline aren't able to form their shells in their infancy (as part of the reduction in alkalinity), and so are dying Klein, 391
  • Young sea animals are particularly affected by climate effects, oil contamination, etc. Disasters can wipe out a generation at a time. Juvenile animals are often not accounted for in environmental impact assessments. Klein, 388
  • "Entire regulatory systems are premised on the assumption that all members of the population act, biologically, like middle-aged men. ... Until 1990, for example, the reference dose for radiation exposure was based on a hypothetical 5\'7\" tall white man who weighed 157 pounds." biologist Sandra Steingraber, quoted in Klein, 384

Ocean dead zones

  • Runoff: fertilizers and pesticides, lawn maintenance, etc. leach into the ocean. Because of this, there are now more than 400 "dead zones" in the ocean, where nitrogen & phosphorous excess from this runoff cause algal blooms. Decomposition of these vast quantities of algae sucks oxygen from the surrounding water, making an oxygen-free space where sea creatures often cannot survive. Barber, 216

Phytoplankton death and positive feedback cycles

  • Phytoplankton levels are good indicators to ocean environment changes. They are the basic/lowest food on the food chain. There has been a 40% decline in phytoplankton since 1950. Barber, 217
  • Impacts of phytoplankton decline (we see this on a small scale during El Nino climate cycles): seabirds and marine mammals starve and die. Phytoplankton typically release the sulfurous gases which help in cloud formation, so less phytoplankton --> less cloud cover --> lower albedo --> faster global warming. Phytoplankton use photosynthesis to convert CO2 into O2 for the air, usually this accounts for 50% of the oxyen production on earth (but we'll have less if the phytoplankton die). Phytoplankton typically serve as a carbon sink when they die and sink to the bottom of the ocean. Barber, 217-218
  • "A 40 percent decline in phytoplankton makes the destruction of the rainforests seem almost insignificant by comparison. If there is less phytoplankton to store carbon, there's less of a buffer against global warming. More than that, it increases the inevitability of a disastrous positive feedback cycle in which warmer water supports fewer phytoplankton, which then take up less CO2 from the atmosphere, which causes the surface water to warm even more to the greenhouse effect. And on it goes." Barber, 218

Ocean reduction in alkalinity (aka acidification)

  • Carbon dioxide dissolves in water to form an acid Kolbert, 112
  • Ocean (70% of earth's surface) and air exchange gases wherever they touch. The exchange is typically roughly equal, but now more CO2 enters the water than returns - so we are now constantly adding CO2 to the ocean on the order of seven pounds per American per day Kolbert, 113-114
  • Ocean is usually alkaline, on the order of 8.2 pH at preindustrial levels. In 2014 it was at 8.1 (30% less acidic than previously). If we continue at current rates, we'll hit 8.0 by 2050 and 7.8 by 2100 (150% more acidic than at the start of the industrial revolution). Kolbert, 114
  • There are CO2 vents in the ocean (e.g. near Castello Aragonese) which let us see a gradient of alkalinity in the ocean & research what a future ocean would look like Kolbert, 114-117
  • In a survey of species around CO2 vents, 1/3 of the species found far from the vent existed very close to the vent at pH 7.8 Kolbert, 118
  • "The biggest tipping point, the one at which the ecosystem starts to crash, is mean pH 7.8, which is what we're expecting to happen by 2100." Hall-Spencer, quoted in Kolbert, 118
  • "Why is ocean acidification so dangerous? The question is tough to answer only because the list of reasons is so long. Depending on how tightly organisms are able to regulate their internal chemistry, acidification may affect such basic processes as metabolism, enzyme activity, and protein function. Because it will change the makeup of microbial communities, it will alter the availability of key nutrients, like iron and nitrogen. For similar reasons, it will change the amount of light that passes through the water, and for somewhat different reasons, it will alter the way sound propagates. (In general, acidification is expected to make the seas noisier.) It seems likely to promote the growth of toxic algae. It will impact photosynthesis– many plant species are apt to benefit rom elevated CO2 levels– and it will alter the compounds formed by dissolved metals, in some cases in ways that could be poisonous." Kolbert, 120-121
  • Calcifiers will not be able to build their shells because of insufficient numbers of calcium ions, and eventually the corrosive properties of insufficiently alkaline ocean water. When CO2 dissolves in water, it forms carbonic acid (H2CO3), which is attracted to carbonate ions and thus makes them unavailable to calcifiers. Kolbert, 121-122, 136
  • 1/3 of the CO2 humans have put into the air has been absorbed by the oceans (150 billion metric tons) Kolbert, 123
  • The speed at which humans are restoring sequestered carbon to the atmosphere is unprecedented in natural history Kolbert, 124
  • Coral is a calcifier, and ocean acidification kills coral reefs, which is the home to huge numbers of species Kolbert, 135
  • Coral reefs will probably die before ocean acidification gets the chance because of overfishing (leading to growth of its ecological competitor, algae), deforestation (which reduces water clarity through siltation), and dynamite fishing. They're also susceptible to bacterial infection when made weak by any of the above. Kolbert, 141

Sea chimneys

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