ESS Topic 4 HL

Evaporation

water changing form from a liquid to a gas

Evapotranspiration

water moving through a plant and then evaporating out of a leaf stomata

Sublimation

water changing form from a solid to a gas

Condensation

water changing form from a gas to a liquid

Melting

water changing form from a solid to a liquid

Freezing

water changing form from a liquid to a solid

Deposition

water changing form from a gas to a solid

Advection

water moving through the atmosphere as a cloud driven by the wind

Precipitation

water moving as a liquid from the atmosphere to the surface of the earth

80%

the amount of precipitation that occurs over the oceans

70%

the amount of Earth's surface covered in water

Run-off

water flowing across the surface of the earth to a collection point

Infiltration

water being absorbed into the soil

Percolation

water moving downwards through the soil column to become ground water

Ground water flow

water moving beneath the surface of the earth, either to seep out at the surface as a spring or to join a body of water

Stream flow

water moving across the surface of the earth, usually in the form of a river

Flooding

when precipitation exceeds the capacity of streams and rivers to hold it all

Oceans

store 97% of Earth's water

0.3%

the amount of water that is available for human use

Largely responsible for regulating Earth's climate

The Global Conveyer Belt

Thermohaline

Temperature and salinity

Europe is temperate because

heat is released from the oceanic conveyer belt

Positive feedback

warmer oceans will absorb less carbon dioxide, thereby enhancing global warming

Cold water

dense, will sink

Warm water

will float

Increases in salinity

increases in density of water

Decreases in salinity

decreases in density of water

Melting of the Greenland Ice Sheet

decreases density of water in the North Atlantic, potentially slowing down the Oceanic Conveyer Belt

Aquifer

An underground formation that contains groundwater

Irrigation

A human activity that increases productivity but leads to reductions in fresh water availability

Salinization

A negative impact of over irrigation

Reservoirs, desalination, rain water harvesting

Possible solutions to a lack of fresh water

The tragedy of the commons

Describes unsustainable use of resources because nobody owns or regulates the resources. Everyone will try to use them as quickly as possible so that their competitors cannot

Maximum sustainable yield

An estimate how many fish can be removed from a fishery before the fishery starts to collapse

BOD

The amount of oxygen required for micro-organisms to break down a pollutant

Eutrophication

The consequences of extra phosphorous and nitrogen being added to an aquiatic system

Indicator species

The presence or absence of these can inform you about whether or not a body of water is polluted

Algal blooms can lead to a:

dead zone

optimal sustainable yield (OSY)

safer approach, half the carrying capacity, greater safety margin

flash flooding

more likely to occur in an urban area because of the lack of permeable surfaces

Human impacts that effect the water cycle

Water withdrawal (domestic, agriculture, industrial), discharge of pollution, cities, canals, dams

Examples of human impacts

The Aral sea is gone because all of the water flow has been diverted for irrigation, the Ganges basin has been deforested so local flooding has increased

Benefits of vegatation

Holds soil together with roots to prevent erosion, absorbs water to prevent flooding

El Nino-Southern Oscillation (ENSO)

A reversal of wind and water currents in the South Pacific, leading to drought in Indonesia and flooding in California

recharge

new water that enters the aquifer from the surface, typically much lower than withdrawal rates

Grey Water

the relatively clean waste water from baths, sinks, washing machines, and other kitchen appliances that can easily be reused or reclaimed

continental shelf

A shallow extension of the continent into the ocean, causes upwelling. Provides 50% of all ocean productivity while only occupying 15% of ocean space

organic waste

Comes from plant or animal sources, Animal waste from feedlots contributes to higher BOD levels in local water supplies

Inorganic waste

Comes from non-living sources, includes fertilizers, detergents, toxic metals, hot water, oil, radiation, light, noise, etc

point source pollution

Pollutants discharged from a single identifiable location (e.g., pipes, ditches, channels, sewers, tunnels, containers of various types).

non-point source pollution

pollution that does not have a specific point of release

Red Tide

a specific type of algal bloom (triggered by eutrophication) that occurs when dinoflagellates (red algae) reach large

numbers, resulting in a red or brown color tide. These algae are toxic meaning that fish harvested from these blooms are often inedible

Strategies for reducing pollution by altering human behavior

Ban or limit detergents with phosphate, plant buffer zones, educate farmers about more efficient fertilizing strategies

Strategies for reducing pollution at the point of emission

Treat wastewater for nitrates and phosphates, treat sewage

Strategies for reducing the impacts of pollution by cleaning or restoring an environment

Pump air through the body of water, dredge sediments with high nutrient load, remove excess weeds or algae mechanically or chemically (herbicide or algicide), restock with appropriate plants and animals

carbon sequestration

the oceans ability to store carbon short term is dissolved carbon dioxide and long term as deposited biomass

stratification

the characteristic of water in which it forms layers based on temperature differences

clarity

the ability of water to transmit light, down to about 100 meters, allowing photosynthesis to occur

upwelling

occurs along continental shelfs, where cold nutrient rich water is forced to the surface, allowing high rates of productivity and dense fisheries

water footprint

a measure of how much water is used by individuals or societies, useful in assessing sustainability

citizen science

scientific research conducted in whole or part by distributed individuals, many of whom may not be scientists, who contribute relevant data to research using their own computing devices.

water stress

similar to water scarcity, but takes into account water quality, and is set at less than 1,700 cubic meters per person per year

pros of desalination

ample supply of sea water, many people live near coasts

cons of desalination

energy intensive (usually fossil fuels) and produces toxic saline sludge as a waste product

pros of reservoirs

aids in flood control, produces a reservoir that can be used for recreation or for aquaculture

cons of reservoirs

may displace local populations, changes the ecosystem and may block migration, results in less sedimentation at river deltas

bycatch

the capture and death of non-target organisms by fishing nets

anoxic

an area with no oxygen as a result of eutrophication

hypoxic

an area with reduced oxygen as a result of eutrophication

biotic index

an indirect measure of pollution by assessing the presence and absence of pollution sensitive and insensitive species

water quality index (WQI)

a measure of the safety and cleanliness of water resources