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18 questions
We know a spring has ________ feedback because when you compress or stretch the spring in the one direction, it opposes you with its force in the ________ direction.
positive, opposite
positive, same
negative, same
negative, opposite
Warming ocean temperatures increase the rate of dissolved ocean CO2 outgassing, which raises earth's temperature. This is ___.
a positive feedback loop
a negative feedback loop
not a feedback loop
a neutral feedback loop
Warming air temperatures in the arctic/tundra regions thaws (melts) more permafrost, which releases greenhouse gas methane, that holds more heat in the earth's air. This is ___.
a positive feedback loop
a negative feedback loop
not a feedback loop
a neutral feedback loop
An increasing atmospheric CO2 concentration increases the rate of photosynthesis by plants and ocean phytoplankton, so they take more CO2 out of the air. This is ___.
a positive feedback loop
a negative feedback loop
not a feedback loop
a neutral feedback loop
An increase in temperature and droughts from global warming causes more frequent and severe wildfires, which release more greenhouse gas CO2 into the air. This is ___.
a positive feedback loop
a negative feedback loop
not a feedback loop
a neutral feedback loop
Global warming increases ocean water evaporating into the air. Water vapor is a greenhouse gas holding heat into the earth. This is ____.
a positive feedback loop
a negative feedback loop
not a feedback loop
a neutral feedback loop
An increase in atmospheric temperatures increases ocean evaporation, causing more white clouds that reflect sunlight back to space, cooling earth. This is ___.
a positive feedback loop
a negative feedback loop
not a feedback loop
a neutral feedback loop
An increase in deforestation by humans (converting woodlands into homes, shops, agricultural fields, etc.) leads to higher atmospheric CO2 concentrations. This is ___.
a positive feedback loop
a negative feedback loop
not a feedback loop
a neutral feedback loop
The albedo (reflectivity) of ice = 0.6, but the albedo of water = 0.06. An increase in global temperatures melts more polar sea ice, so less sunlight reflects back to space. This is ___.
a positive feedback loop
a negative feedback loop
not a feedback loop
a neutral feedback loop
An increase in atmospheric CO2 causes global warming that slows the ocean conveyor belt, which reduces the rate of nutrient upflow to phytoplankton that take CO2 out of the air. This is ___.
a positive feedback loop
a negative feedback loop
not a feedback loop
a neutral feedback loop
Volcanoes release SO2 that reflects sunlight back to space, cooling the earth. If an increase in global warming caused more volcanic eruptions, this would be ___.
positive feedback loop
a negative feedback loop
not a feedback loop
a neutral feedback loop
A increased use of cars in developing countries causes more global warming. This is ___.
a positive feedback loop
a negative feedback loop
not a feedback loop
a neutral feedback loop
We know the extra atmospheric CO2 is from burning fossil fuels and deforestation, not from volcanoes, because the CO2 has a higher fraction of ____.
12C from plants.
13C from plants.
14C from plants.
13C from coal.
We know the extra atmospheric CO2 is from burning fossil fuels, not from deforestation, because the CO2 has a ___.
higher fraction of 13C, as from plants.
lower fraction of 14C, as from coal.
higher fraction of 12C, as from plants.
lower fraction of 13C, as from coal.
The amount of 14C in a sample is halved in each half life of _____ years.
573 years
5730 years
57,300 years
57.3 years
Methane clathrate hydrates are ____________ molecules in clathrate cages made of water molecules.
ethane
methane
octane
butane
If the methane clathrate hydrate frozen in permafrost and seabeds thaws and escapes to the atmosphere, it would _____ the earth, since it is a powerful ______.
cool, reflector
warm, greenhouse gas
dissolve rocks on, acid
slow the winds of, friction brake
The radiation power emitted (sent out) from an object is proportional to T4, where T is the temperature in Kelvin, so if the earth becomes 1% hotter, it radiates 1.014 times more heat to space. This is ___.
positive feedback.
negative feedback.
neutral feedback.
no feedback.
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