Exam 1 Vocab Flashcards
How much of Earth’s water is salty
97.3%
How much of Earth’s freshwater is stored in ice
68%
How much of Earth’s freshwater is stored in deep groundwater
30%
How much of Earth’s freshwater is in lakes and streams
0.32%
where does most precipitation fall
back into the ocean
what happens to most terrestrial precipitation
it evaporates
Human get to use the overland flow of water minus the amount of freshwater lost in floods and inaccessible areas. How much is this?
9,000 km^3 per year
What happens if water use exceeds availability
no longer in steady state so water must come somewhere else (mining groundwater, desalinizing sea water, melting glaciers)
How much water do we use annually?
We used a little more than half of what’s available annually (4,860 km^2)
What are the two overarching categories MEA has for accessing the value of water
Utilitarian and Non-utilitarian
What are the two sub categories of Utilitarian value
direct and indirect values
What are the two sub categories of direct values
consumptive and non-consumptive
What are utilitarian values
provisioning, regulating, or supporting aspects; something that affects us
What are non-utilitarian values
religious, ethical or philosophical aspects; how water makes you feel
What are consumptive direct values? Name an example
Material goods that are consumed; seafood
What are some examples of non-consumptive direct use values?
money spent on sports or recreation associated with freshwaters
What are some examples of indirect use values?
Ecosystem services including making water clean, irrigation, flood control, and ecosystem processes
What is the estimated value of indirect use values?
trillions
How much of all watercourse is in small streams?
two-thirds
What happens to energy and nutrients in intact stream ecosystems?
it is retained and cycled
What happens when aquatic ecosystems are changed?
loss of leaves (reduced nutrient retention and diversity), pulsing due to increased impervious surfaces (nutrient retention reduced and flushed out), increased nutrient inputs from agricultural and domestic run off, watersheds become more like pipes
Explain dead zones
more nutrients=more phytoplankton, phytoplankton dies and decomposes, microbial metabolism depletes oxygen, fish and other animals move on or die
List some water based scientific units
temperature, mass, energy (calorie), viscosity (centistoke)
What are some unusual properties of water
ice floats, universal solvent, high heat capacity, surface tension, liquid at normal temperatures and pressures
