Final Study Guide 11 Flashcards
Anthropocene
1
Q
Why do we think that the late twentieth-century global warming is due to human activity?
A
- We believe that global warming is created by the carbon gases released by burning fossil fuels. The carbon gases are green house gasses that absorb heat from the sun and trap it in Earths atmosphere.
- temp has risen with industrialization
2
Q
Why is the ocean conveyor belt important?
A
- Responsible for moving warm, relatively fresh surface water around until it cools down. It accumulates salt and sinks because it’s now colder and is more dense.
- Warm surface waters are depleted of nutrients and carbon dioxide, but enriched again as travels through conveyor belt as deep or bottom layer. Base of world food chain (algae and seaweed) rely on nutrients from deep water
- The great ocean conveyor is the circulation system of the ocean. The conveyor transports both energy and matter around the world in an identifiable circulatory pattern. This system is conceptualized as acting like a giant conveyor belt taking heat energy across immense ocean distances in the air-driven currents of the oceans as well as any material substances that happen to have found their way in there. The conveyor is of great importance to the climate and may be linked to carbon dioxide levels in the air.
3
Q
What are the major effects of global warming?
A
- Sea level rise
- Shoreline decrease
- Retreating glaciers
- Warmer
- increase in atmospheric CO2
- Arctic ocean melting
- Loss of sea and land ice
4
Q
Carbon Dioxide
A
- A driver of Global Warming is CO2 in the Atmopshere
- Greenhouse gas
- Earth inhales CO2 in the summer, exhales in the winter
> Correlated to growth of plants – live in summer, die in winter - C02 in Glacial deposits – record of C02 levels –
- Prior 500 years decrease, dramatic increase in 1900’s industrial revolution
- Exists as gas (CO2), solute (carbonate, ions), and solid (organic carbon)
5
Q
Carbon Cycle
A
- the series of processes by which carbon compounds are interconverted in the environment, chiefly involving the incorporation of carbon dioxide into living tissue by photosynthesis and its return to the atmosphere through respiration, the decay of dead organisms, and the burning of fossil fuels
- regulates climate over long time scales
- CO2 in atmosphere from volcanic eruptions → CO2 in rain weathers continental rocks and carries HCO3 to oceans → HCO3 forms CaCO3 in ocean → goes to seafloor → subduction and CaCO3 converted to CO2
- Planetary C Cycle: can only happen on a planet with tectonic recycling
- changes in CO2 levels → changes in rate of weathering
- CO2 increase → temp increases → rate of weathering increases → CO2 levels decrease
> weathering impact is more important and more efficient at higher temps
> negative feedback loop: earth can never get too hot or cold
6
Q
Methane
A
atmospheric methane is a greenhouse gas, simplest alkane, main component of natural gas
7
Q
Global Warming
A
Warming of the earths atmosphere due to greenhouse gasses
8
Q
Heat Content
A
- The amount of heat stored in the oceans.
- If oceans warming up, earth is absorbing more energy.
- Can lead to worse storms
- Ocean releases heat in El Nino events
9
Q
Glaciers
A
- Slowing moving mass or river of ice formed by the accumulation and compaction of snow on mountains or near the poles
- Have been receding in years
10
Q
Antarctic
A
- Antarctica sits on a land mass (north pole ice), the dynamics of which our understanding is incomplete.
> Ice streams (which are under the top ice) move down, can cause crevices.
> The entire ice shelf can move - Antarctica has increased motion in ice streams, ice on land will make the sea level rise when it melts where-as ice bergs melting will not affect sea levels much.
11
Q
Arctic
A
- polar region at northernmost part of earth
- negatively affected by climate change
12
Q
Ice Loss
A
- Greenland arctic has been losing ice for over 50 years
- Ice loss can lead to rising sea levels (Glacier melting but not ice berg melting)
13
Q
Glacier Retreat
A
- Due to the increase of greenhouse gases, glaciers have been shrinking due to the melting of the freshwater
- Effect of global warming.
- Arctic glaciers have become smaller since 1953
- Ex from slides: Effects glacier national park, Austria’s Pasterze Glacier
14
Q
Sea Level Rise
A
- Effect of Warming of climate system – since 1950s sea level has risen
- Caused By: Thermal Expansion (molecules spread out as temperature rises )50% and Melting 50%
- Sea level will rise from melting of glaciers
> Though not of just ice: Icebergs will not affect it much. - Will flood the continents
- Opens new shipping routes - Not all effects of global warming are negative.
- Effects wildlife
- Can increase El Nino effects – El Nino comes with high sea levels
- Sea level change has been larger than mean rate during past two milienia, over 1901-2010 the mean rate was 0.19 m.
15
Q
Thermal Expansion
A
- the tendency of objects to change in volume in response to a change of temperature
- Warming of the oceans – 50% responsible for expansion of water molecules = rise of sea level
> If you heat a material, it will expand and will have less density and will rise. - Correlation between sea level and thermal expansion
16
Q
Temperature Proxy
A
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