River Runoff - Case Study 1
Beman et al Showed:
80% of fertilization events stiumlated phytoplanktonblooms in the Gulf of Californai within days.
- Vistually no ill ecosystem in fertilizer runoff 
River Runoff - Case Study 2
Eutrophication - nutrients from land running off into the ocean.
- Cause lots of phytoplankton/algea to boom! 
- They then die, and decay, which consumes oxygen. 
- Bottom of ocean becomes ocean deprived. 
- Without ocean, fish and living organisms all die.
- Known as a "dead zone". This is seasonal; they come back next year
- Causes lot of nitrogen oxide to be emitted. Which is 200x more potent than CO2!
Example
Gulf of Mexico. The Mississippi River dumps lots of fertilizers into the Gulf of Mexico. 
We are seeing a phytoplankton boom along the shore! Results in a seasonal dead zone. 
"Salmon Forests"
During rainy season, salmon swim from the ocean upstream.
- Caught by bears.
- Many fish are dragged into forest to be eaten, and much is wasted and lies there to rot. 
- These salmon "feed" conifer forests; 75% of total nitrogen comes from salmon!
- And this effect is widespread. They cover lots of 

River Runoff

Atmospheric Deposition

Atmospheric Deposition
Mineral dust is mainly oxides (including iron) and carbonates that constitute Earth's crust. Atmosphere deposits (through winds) a lot of this stuff into the ocean, including iron. Living organisms need iron to survive. 
- Most of iron being blown around is natural, not anthropogenic.
- Most places of ocean have lots of iron, 
Nitrogen
External nitrogen supply (from industrialized nations) pumps more nitrogen through atmospheric deposition into the ocean.  How much?
- 81% of all nitrogen deposited on surface ocean from dust is from human activities.
- 32% of all nitrogen entering the surface ocean is from human activities. 
Iron
Living organisms need iron to survive. 
- Most places of ocean have lots of iron, except for areas around Antartica. 

Ice Sheet Melting

Case Study 1: Antartica
Ice melting here.
Polynyas
Areas of ocean surrounded by ice. 
- Antartic polynyas are hot spots of productivity. Productivity is a function of nearby ice shelves melting. These ice shelves have lots of nutrients, especially iron, so cause phytoplankton boom. 
Case Study 2: Greenland
Ice also melting here. 
Effects
- Contributes to seas level rise
- Enhances ocean productivity. 
Iron
Lacking iron. Melting ice causes phytoplankton boom. 
Glaciers
Glaciers melt and enter ocean. 
0.76mm per year. 
Thermal Expansion
Thermal expansion due to ocean warming. When heat enters the ocean, it expands it (rises the ocean level). Today it is the largest contributer
1.10mm per year.

Sea Level Rise

Ice Sheets
Melting of Greenland ice sheet
0.33mm per year.
Melting of Antartica ice sheets
0.27mm per year.
Changes to land water storage
Pumping groundwater lowers land level and raises sea level. 
0.38mm per year. 
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