Oceanography Exam 2 Deck 2

Melting sea ice does not raise sea level because it already floats in the ocean

Does melting sea ice raise sea level?

Main causes: melting continental glaciers and thermal expansion of seawater

What causes sea level rising?

Satellite data show about 3 mm per year

how much does sea level rise?

Has risen about 10–25 cm over the past 100 years

how much has sea level risen in the past 100 years?

Dissolved CO₂ forms carbonic acid, Lower pH makes shell secretion harder, Dissolves coral, Harms larvae and fish reproduction

What are some side effects of increased acidification?

Arctic sea-ice area has been decreasing, Antarctic ice shelves are shrinking

What are some effects of climate change on sea ice?

Freshwater from melting glaciers lowers salinity and density at the surface, which can

inhibit downwelling and alter deep-water circulation.

what happens when glaciers melt?

Ocean absorbs about 93% of trapped heat

How much heat does the ocean absorb?

Ocean absorbs about 25% of CO₂ added to the atmosphere

How much CO2 does the ocean absorb?

Increasing ocean temperature, Changes in deep-water circulation, Changes in sea ice, Seawater acidification, Rising sea level

What are 5 ocean changes due to climate change?

CO₂, CH₄, H₂O vapor

What are key greenhouse gases?

Earth absorbs shortwave solar radiation, Earth re-emits longwave infrared radiation, Greenhouse gases absorb some of that infrared energy and warm the atmosphere

What is the greenhouse gas effect?

The lecture links increasing atmospheric CO₂ since the Industrial Revolution to a stronger greenhouse effect and atmospheric warming.

What is the effect of the Industrial Revolution?

The oceanic biological pump moves carbon from the atmosphere through the ocean and into seafloor sediments by photosynthesis, shell-making, feeding, and death. This makes the ocean a sink for CO₂.

What is the oceanic biological pump?

Amplify change = positive feedback, Reduce change = negative feedback

What can feedback loops do?

Hydrosphere, Lithosphere, Atmosphere, Biosphere, Cryosphere

What are spheres in the Earth’s climate conditions?

Climate involves long-term atmospheric conditions and the ocean is the largest part of Earth’s climate system

How does the climate relate to the ocean?

Biological pollution includes non-native/invasive species that outcompete native species. Examples from the lecture include zebra mussels, lionfish, and Caulerpa taxifolia

What is biological pollution?

Nurdles = pre-production plastic pellets, Microbeads = tiny plastic particles 1–5 mm, Plastic is transported by rivers and then redistributed by surface currents, helping form garbage patches.

What are some things to know about plastic?

Plastic is the main form of solid marine debris: Floats, Degrades slowly, Entangles organisms, Is mistaken for food, Can absorb toxic substances like DDT and PCB

What are some more plastic facts?

Bacteria convert elemental mercury into methyl mercury, which is highly toxic. The lecture uses Minamata Bay as the major case study and links mercury poisoning to neurological disease.

What is mercury’s effect?

Bioaccumulation = pollutant concentration builds up in one organism, Biomagnification = concentration increases up the food chain

What are some terms for pollution?

Both highly toxic, DDT caused thin eggshells in birds, PCBs are carcinogenic, Both were banned in the 1970s, They are persistent organic pollutants that remain in seawater and sediments for a

long time

DDT and PCB effects