The World Water Monitoring Project encourages citizen scientists to test the turbidity, temperature, dissolved oxygen, and pH of local water resources.
Photograph by Jackie Karsten, National Geographic
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    On September 18, 2003, the world first celebrated World Water Monitoring Day. Today, the program has become the World Water Monitoring Challenge (WWMC), a citizen science project which encourages people to test and protect water resources all year long.
    Kits provided by the World Water Monitoring Challenge test four indicators of water quality: turbidity, pH, temperature, and dissolved oxygen. Turbidity is the clarity of water. Turbidity can be affected by the amount of erosion or runoff in an area. pH tests the amount of acid in water. pH can be affected by chemicals in runoff and even rain. A body of water’s temperature can be affected by runoff and land development, which often removes trees and other vegetation that provide shade to streams and ponds. Dissolved oxygen is the amount of oxygen in a body of water. Oxygen is critical for living things. Dissolved oxygen can be affected by temperature (cold water can support more oxygen than warm water) and the presence of organisms such as bacteria and algae.
    Through the World Water Monitoring Challenge, individuals and classrooms can share their data with other citizen scientists around the world through charts, graphs, and maps.
  • Term Part of Speech Definition Encyclopedic Entry
    acid Noun

    chemical compound that reacts with a base to form a salt. Acids can corrode some natural materials. Acids have pH levels lower than 7.

    algae Plural Noun

    (singular: alga) diverse group of aquatic organisms, the largest of which are seaweeds.

    bacteria Plural Noun

    (singular: bacterium) single-celled organisms found in every ecosystem on Earth.

    celebrate Verb

    to observe or mark an important event with public and private ceremonies or festivities.

    chart Noun

    diagram, often in the form of a graph or table, with information on the relationships between the subjects represented.

    citizen science Noun

    science project or program where volunteers who are not scientists conduct surveys, take measurements, or record observations.

    Encyclopedic Entry: citizen science
    clarity Noun

    clearness or transparency.

    critical Adjective

    very important.

    dam Noun

    structure built across a river or other waterway to control the flow of water.

    data Plural Noun

    (singular: datum) information collected during a scientific study.

    development Noun

    construction or preparation of land for housing, industry, or agriculture.

    dissolved oxygen Noun

    measure of the amount of oxygen in a substance, usually water.

    encourage Verb

    to inspire or support a person or idea.

    erosion Noun

    act in which earth is worn away, often by water, wind, or ice.

    Encyclopedic Entry: erosion
    graph Verb to depict the relation between certain sets of numbers by plotting them with reference to a set of axes.
    indicator Noun

    sign or signal.

    lake Noun

    body of water surrounded by land.

    Encyclopedic Entry: lake
    map Noun

    symbolic representation of selected characteristics of a place, usually drawn on a flat surface.

    Encyclopedic Entry: map
    monitor Verb

    to observe and record behavior or data.

    ocean Noun

    large body of salt water that covers most of the Earth.

    Encyclopedic Entry: ocean
    pH Noun

    measure of a substance's acid or basic composition. Distilled water is neutral, a 7 on the pH scale. Acids are below 7, and bases are above.

    reservoir Noun

    natural or man-made lake.

    Encyclopedic Entry: reservoir
    resource Noun

    available supply of materials, goods, or services. Resources can be natural or human.

    river Noun

    large stream of flowing fresh water.

    Encyclopedic Entry: river
    runoff Noun

    overflow of fluid from a farm or industrial factory.

    Encyclopedic Entry: runoff
    stream Noun

    body of flowing water.

    Encyclopedic Entry: stream
    temperature Noun

    degree of hotness or coldness measured by a thermometer with a numerical scale.

    Encyclopedic Entry: temperature
    turbidity Noun

    cloudiness or lack of transparency.

    vegetation Noun

    all the plant life of a specific place.

    water quality Noun

    chemical, physical, and biological characteristics of water for a specific purpose such as drinking.

    watershed Noun

    entire river system or an area drained by a river and its tributaries.

    Encyclopedic Entry: watershed
    well Noun

    a hole drilled in the Earth to obtain a liquid or gaseous substance.