L10 - Ice Sheets in the Earth's System

Question 1

What must 3 impacts need to be considered?

Answer 1

1. Impacts of Microbes
2. Impacts of Chemical Weathering
3. Impacts of Melting

Question 2

What impact do microbes have on the oceans?

Answer 2

They fertilise them

Question 3

What is a bioavailable form?

Answer 3

An easy to use form as opposed to one that requires an enzyme or a further energy source

Question 4

Where does tiny-scale nutrient cycling take place?

Answer 4

In Cryoconite Holes

Question 5

Which 3 nutrients can be looked at for nutrient cycling and what is focused on for each?

Answer 5

1. Carbon (organic vs. inorganic)
2. Nitrogen (nitrogen fixing vs. denitrification)
3. Phosphorus (phosphorus extraction from rocks vs. decomposition)

Question 6

What can we measure for Carbon?

Answer 6

The chemical signature

Question 7

How much bioavailable Carbon did Lawson et al. (2014) find from the Leverret Glacier?

Answer 7

26-53% which is equivalent to a river system

Question 8

How much bioavailable Carbon did Hood et al. (2009) find from the the Gulf of Alaska?

Answer 8

20-66%

Question 9

Who said that glaciers have 0.6% of global DOC and 1% of POC?

Answer 9

Hood et al. (2015)

Question 10

Who said that by 2050 glaciers will released 1.5x Amazonian Rivers DOC?

Answer 10

Hood et al. (2015)

Question 11

What are the 2 most bioavailable forms of Phosphorus?

Answer 11

1. SRP (Soluble Reactive Phosphorus)

2. NaOH-P

Question 12

What would a large catchment give?

Answer 12

More P

Question 13

Glaciers export what 2 forms of P?

Answer 13

Dissolved and Particulate

Question 14

During what events are there pulses of P and N?

Answer 14

Outburst Events

Question 15

Who found that the Leverret Glacier exports as much P as the Mississippi does to the Gulf of Mexico? and how much was it?

Answer 15

Hawkings et al., 2016

400,000 metric tons

Question 16

Who found that concentrations of P were 10x greater than Arctic river waters at the Leverret Glacier?

Answer 16

Hawkings et al., 2016

Question 17

Nitrogen yields from ice sheets are how much greater than they are for Arctic Riverine Systems?

Answer 17

Twice as much

Question 18

Give 5 impacts that glaciers can have on the global system

Answer 18

1. Release of micronutrients such as silica and iron
2. LNHC (Low Nutrient High Chlorophyll Zone) zones (ice sheets dump Fe where needed)
3. IRD
4. Meltwater plumes darken the water
5. Ice Albedo Feedback

Question 19

What does SLR have the potential to disrupt?

Answer 19

Ocean Currents

Question 20

What 2 types of interactions with the earths system need to be considered?

Answer 20

1. Ocean-Atmosphere

2. Ocean-Ice Sheet