GEI Exam 3 Flashcards
most essential molecule for all living things
water
How humans are constantly losing water
perspiration and exhalation
amount of water needed to produce 1 tomato
3 gallons
amount of water needed to produce 1 loaf of bread
150 gallons
amount of water needed to produce 1 pound of beef
1,600 gallons
amount of water needed to produce 1 ton of steel
63,000 gallons
70% of global water usage
irrigation
21% of global water usage
public supply
11% of global water usage
industry
rank of top 3 water usages
- irrigation
- public supply
- industry
How much water does Earth have (cubic km)
~1.4 billion cubic km of water
ocean water makes up what percentage of water on Earth
97%
largest reservoirs of fresh water (but unavailable)
glaciers, ice bergs, and sea ice
largest available reservoir of fresh water
groundwater
most commonly used water resources (but less than 0.01% of world’s water)
rivers and lakes
contains 95% of Earth’s water
oceans
average depth of the oceans
3.6 km (2.2 miles)
maximum ocean depth (in Mariana Trench in Pacific)
11 km (7 miles)
names of the 5 oceans
Atlantic, Pacific, Indian, Arctic, and Southern
Increases in fall and water
partially melts in the spring and summer
overall decrease in last few decades
trend of ice mass
White color of ice gives it an albedo (reflectivity) of 0.9 (0-1), which makes it…
good at reflecting sunlight
Arctic animals include…
polar bears, foxes, puffins, reindeer, seals, etc.
Antarctic animals include…
penguins, seals, whales, small invertebrates, etc.
Arctic and Antarctic animals rely on ice for…
foraging
Effects of melting polar ice
rising sea levels
coastal flooding
alteration of ocean circulation patterns, more severe weather events
types of ice
- glaciers
- ice bergs
- sea ice
forms at the poles and on mountaintops
snowfall compression into ice
largest source of fresh water
provides river water and groundwater to lower elevation
glaciers
type of glacier
typically >20,000 sq miles in size
2 major sheets in Greenland and Antarctica
reduction allows permafrost to melt faster, releasing greenhouse gases
ice sheet
type of glacier
channels of moving ice sheets
travel down slopes into sea
ice streams
type of glacier
edge of an ice sheet extending off land
ice shelves
floating pieces of ice that broke off of ice sheets
nutrients into ocean, helping aquatic life
ice bergs
free-floating ice in polar regions
excludes salt, allowing it to float
sea ice
water located underground in saturated zone of soil and fractured rock
recharged by precipitation and seepage
groundwater
upper surface of the saturated zone
water table
how much of U.S. population relies on groundwater for drinking
~50%
large area of groundwater, often tapped with wells for irrigation
aquifer
Reserve of groundwater located in most of NE, extending south to northern TX
Ogallala (High Plains) Aquifer
swamps, marshes, bogs
saturated with water most of the year
water-demanding or -tolerating plants
carbon sequestration
wetlands
important for irrigation, drinking water, biodiversity, and recreation
> 200,000 in U.S.
rivers
joins together to form larger rivers
tributaries
land area drained by a river and all its tributaries
watershed
land adjacent to a river that floods frequently
floodplain
determined settlement patterns all over the world
rivers
created by impounding or damming a river
~1/2 of lakes in U.S.
reservoirs
reduce local flooding, freshwater source in droughts, greater biodiversity, and recreation
benefits of reservoirs
alters biodiversity, interferes with fish migration, displaces people and wildlife
negative impacts of reservoirs
why most precipitation falls around equator
warmer air rises and cools, can’t hold water vapor
actual shortage of water
physical water scarcity
countries lack money or infrastructure to supply safe, reliable water
economic water scarcity
how many people lack access to clean drinking water and sanitation tech
over a billion people
water supply solutions
- aqueducts
- reservoirs
- desalination
- fog nets
irrigation water conservation
native crops
drought-resistant GMO crops
drip irrigation
no-till farming
recharging aquifers with treated waste water
home conservation
water restrictions
native vegetation
low-flow showers and toilets
fix leaky facets
rain barrels for gardens
contamination of water by a chemical, physical, or biological substance
water pollution
small, identifiable places where pollution releases
e.g. livestock manure, industrial factories
point sources
when precipitation or irrigation runs off fields or neighborhoods
carries pollutants over wide area
e.g. fertilizer runoff or urban stormwater
nonpoint sources
oil tanker ran aground in Alaska in 1989
Exxon Valdez oil spill
offshore oil drilling platform in Gulf of Mexico spilled oil for 3 months, natural gas explosion
Deepwater Horizon
Sources of water pollution
- Agriculture
- oil spills
- industrial waste
- physical pollution
- thermal pollution
- pathogens
cause many diseases such as rotavirus, cholera, typhoid fever, and dysentary
comes from sewage
pathogens
from power plant cooling systems
thermal pollution
steps to water treatment
- screens and skimmers remove rubbish, large objects, fats, and grease
- organic solids settle at bottom of tanks are treated by aerobic bacteria, then taken to landfill/incinerator
- water through gravel/stone filter with bacteria for remaining organic matter
- disinfection with chlorine, ozone, or UV light
- discharge water into local river, groundwater recharge, or irrigation
