that's where most of Earth's fresh water is located
What are ice caps?
100
That's the abbreviation for pollution that reduces the oxygen level in a river or lake.
What is BOD?
100
That's the type of ray that reaches polar areas of the planet.
What is an oblique ray?
100
The frozen ground at high latitudes, such as in Siberia and northern Canada.
What is permafrost?
200
They were the first source of our atmosphere's oxygen.
What are cyanobacteria/stromatolites
200
These contain groundwater and can be made of rocks like limestone, sand and gravel, or fractured granite.
What are aquifers?
200
Bacteria, viruses and parasites.
What are waterborne pathogens?
200
That's where we get data about past atmosphere and climate, back to 400,000 years.
What are ice cores?
200
These are 3 examples of greenhouse gases.
What are carbon dioxide, methane, nitrous oxide, water, CFCs...
300
The three types of plate boundary.
What are subduction, divergent, transform.
300
When water passes from plant leaves to the atmosphere.
What is transpiration?
300
These are non-dangerous bacteria from mammalian intestines. They indicate that disease-causing organisms may be present.
What are fecal coliform bacteria?
300
It's another way of saying a substance such as water "holds" heat.
What is heat capacity?
300
These are named after a Serbian scientist, who realized that changes in the Earth's tilt, wobble and distance from the sun cause cyclical climate change.
What are Milankovitch cycles?
400
Those are the 3 basic layers of our Earth, from the center out.
What are the core, mantle and crust?
400
Water that's between salty and fresh.
What is brackish?
400
Below this level of oxygen in a river, most fish can't survive.
What is 2ppm?
400
It's the circulation pattern of air and moisture above the equator, leading to rain forests at 0' latitude and deserts at 30'N or S.
What's a Hadley Cell?
400
He was the first to measure atmospheric carbon dioxide levels systematically, starting in 1958.
Who was Keeling?
500
These are two types of evidence for plate tectonics (the mechanism of continental drift)
What are black smokers, crust thickness, limestone fossil ages and seismic activity (along plate boundaries)
500
Those are three impacts of deforestation on the water cycle.
What is less recharge, more runoff, flooding and less transpiration?
500
These are the units of turbidity.
What are NTUs?
500
Those are the four layers of the atmosphere, in ascending order.
What are troposphere, stratosphere, mesosphere and thermosphere?
500
These tiny particles from volcanoes, forest fires, etc block sunlight and cause global cooling.