• The Arctic is the northernmost region of Earth. 
     
    Most scientists define the Arctic as the area within the Arctic Circle, a line of latitude about 66.5° north of the Equator. Within this circle are the Arctic ocean basin and the northern parts of Scandinavia, Russia, Canada, Greenland, and the U.S. state of Alaska.
     
    The Arctic is almost entirely covered by water, much of it frozen. Some frozen features, such as glaciers and icebergs, are frozen freshwater. In fact, the glaciers and icebergs in the Arctic make up about 20% of Earth’s supply of freshwater.
     
    Most of the Arctic, however, is the liquid saltwater of the Arctic ocean basin. Some parts of the ocean’s surface remain frozen all or most of the year. This frozen seawater is called sea ice. Often, sea ice is covered with a thick blanket of snow.
     
    Sea ice helps determine Earth’s climate. Sea ice has a very bright surface, or albedo. This albedo means about 80% of sunlight that strikes sea ice is reflected back to space. The dark surface of the liquid ocean, however, absorbs about 90% of solar radiation. Due to thermohaline circulation, the Arctic’s thick, reflective sea ice moderates ocean temperatures around the world.
     
    The Arctic experiences the extremes of solar radiation. During the Northern Hemisphere’s winter months, the Arctic is one of the coldest and darkest places on Earth. Following sunset on the September equinox, the Earth’s tilted axis and its revolution around the sun reduce the light and heat reaching the Arctic until no sunlight penetrates the darkness at all. 
     
    The sun rises again during the March equinox, and increases the light and heat reaching the Arctic. By the June solstice, the Arctic experiences 24-hour sunshine.
     
    Life in the Arctic
     
    Marine Ecosystem
    The Arctic ocean basin is the shallowest of the five ocean basins on Earth. It is also the least salty, due to low evaporation and huge influxes of freshwater from rivers and glaciers.
     
    River mouths, calving glaciers, and constantly moving ocean currents contribute to a vibrant marine ecosystem in the Arctic. The cold, circulating water is rich in nutrients, as well as the microscopic organisms (such as phytoplankton and algae) that need them to grow. 
     
    Marine animals thrive in the Arctic. Primary consumers such as jellies and shrimp consume plankton, the basis of the Arctic marine food web
     
    Secondary consumers include fish, seabirds (such as gulls and puffins), and a wide variety of baleen whales, including giant blue whales and bowhead whales. 
     
    Tertiary consumers, animals that prey mostly on other carnivores, include toothed whales and dolphins (such as orcas and narwhals) and pinnipeds such as seals, sea lions, and walruses. 
     
    Scavengers (including some sharks and crabs) and decomposers such as marine worms and algae break down dead and decaying materials. Organic nutrients are thus recycled into the marine ecosystem of the Arctic.
     
    Terrestrial Ecosystems
    The varied landscapes of the Arctic provide for a variety of ecosystems. The Arctic includes the peaks of the Brooks mountain range in western North America, the enormous Greenland ice sheet, the isolated islands of the Svalbard archipelago, the fjords of northern Scandinavia, and the grassland plateaus and rich river valleys of northern Siberia.
     
    Although some forests lie near the Arctic Circle, plant life is mostly limited to grasses, sedges, and tundra vegetation such as mosses and lichens. These autotrophs have the ability to survive despite being covered in snow and ice for much of the year. 
     
    Insects such as mosquitoes and moths are common, especially as icemelt creates ponds during spring and summer. Insects and insect larvae provide a crucial diet for birds, such as wrens and sandpipers, and freshwater fish.
     
    Primary consumers across the region range from tiny lemmings to enormous muskoxen. One of the most familiar Arctic herbivores is the caribou, often known as the reindeer in Europe and Asia.
     
    Secondary consumers include Arctic foxes, and raptors such as owls and eagles. The polar bear, the iconic apex predator of the Arctic, is equally able to hunt on land and around ice floes.
     
    Like the polar bear, many other animals of the Arctic are white: beluga whales, snowy owls, juvenile harp seals. This coloring helps camouflage them in heavy snow and ice. 
     
    Many Arctic animals even change their coloration seasonally. Species of Arctic fox and Arctic hare, for example, are snowy white in winter but molt and grow a brownish or greyish fur coat during the summer months. Even fluffy white baby seals will ultimately grow up to a dark brown—better to blend in with the dark Arctic ocean waters instead of blinding white ice floes.
     
    People in the Arctic
     
    Indigenous Cultures
    People established communities and cultures in the Arctic thousands of years ago, and continue to thrive today. They have all developed smart, innovative ways to adapt to the unique challenges posed by the region’s severe climate.
     
    Housing or other shelter, for example, poses unusual challenges for Arctic peoples. Thick blankets of seasonal snow and lack of abundant trees for lumber historically limited the development of wood or stone structures common in subarctic climates.
     
    Inuit bands in Canada and Greenland, for example, engineered “snow houses”—more commonly known as igloos. Igloos were circular structures made of stacked ice (often sea ice), insulated with snow. The rectangular blocks were stacked in tight spiral pattern, giving the igloo a domed shape. Igloos could hold as few as two and as many as 20 people.
     
    Igloos were just one type of Inuit dwelling. Inuit communities also built tents with poles crafted from driftwood and whale bones or baleen. Animal hides covered these poles, and snow provided excellent insulation.
     
    The historically nomadic Sami (an indigenous people of Scandinavia and northwestern Russia) also built temporary tent-like structures, called lavvu. Instead of relying on driftwood, however, Sami communities had access to the rich taiga, or boreal forests, of the European subarctic.
     
    More permanent Sami structures included storehouses, where foods, textiles, and other valuables could be stored for later use or trade. These storehouses, which resemble log cabins, are notable for being elevated on stilts, centimeters or even meters from the ground. Elevation protected the valuables from excess rot due to snow or water seeping into the storehouse, as well as vermin such as mice or rats.
     
    Today, Arctic cultures such as the Inuit and Sami have access to high-quality building materials and sophisticated structural engineering plans. Still, buildings throughout the Arctic are reliant on efficient insulation and weatherization. (Weatherization is the process of protecting a dwelling from extreme temperature changes, precipitation, and wind.)
     
    Challenges of Indigenous Cultures
    Rights to land and natural resources are an important part of contemporary culture and survival of indigenous peoples in the Arctic. Indigenous Arctic communities face tremendous challenges, often the result of colonization and exploitation of land and energy resources.
     
    For hundreds of years, for instance, European and Asian explorers interacted with Inuit communities in the Canadian Arctic, searching for the North Pole and the elusive “Northwest Passage.” (The Northwest Passage is a sea route connecting the North Pacific and North Atlantic ocean basins.)
     
    Increased contact with Europeans and European Americans often came with conflict. Inuit social structure, schools, and language were replaced with Western traditions.
     
    Starting in the late 20th century, regional, national, and international organizations increasingly recognized the political and cultural sovereignty of Arctic peoples. Rights to land and natural resources are an important part of this sovereignty. 
     
    An agreement between the government of Canada and Inuit bands, for instance, ultimately resulted in the creation of the territory of Nunavut in 1999. Nunavut, Canada’s largest territory, stretches far into the central Canadian Arctic. More than half the population of Nunavut identifies as Inuit, and Inuktitut is the most-spoken language. 
     
    Exploration
    European and Asian exploration of the Arctic began with Viking settlement of northern Scandinavia and Iceland in the 900s. Russian explorers navigated the “Northern Sea Route” of the Northeast Passage and the Siberian Arctic, eventually crossing the Bering Strait in the 1600s.
     
    The pursuit of the Northwest Passage, which would save untold time and money in trade between Europe and Asia, drove Arctic exploration during the Age of Discovery. Explorers such as John Cabot, Martin Frobisher, and Henry Hudson all failed to find an open-water route. The Northwest Passage was not completely navigated until 1906, when legendary Norwegian explorer Roald Amundsen and his crew made the voyage from Greenland to Alaska. Shifting sea ice made the trip hazardous; it took about three years, and required a relatively small ship (a converted fishing vessel).
     
    Resources in the Arctic
     
    The Arctic has enormous deposits of oil and natural gas. In Alaska, many oil companies work with indigenous groups known as “native corporations” to drill and export millions of barrels of oil every year. Alaska’s North Slope contains 6% of the largest oil fields in the United States and one of the 100 largest natural gas fields.
     
    Engineers and geographers estimate that oil and gas deposits in the Arctic make up 13% of the world’s undiscovered petroleum resources, and 30% of undiscovered natural gas resources.
     
    The Arctic is also rich in minerals, such as nickel and copper ore. Mineral resources also include gemstones and rare earth elements, which are used in batteries, magnets, and scanners. Some of these mineral deposits are underground, while others are buried beneath the Arctic Ocean. 
     
    Mines and drilling operations are often dependent on the weather. In the winter, machinery can freeze, and the frozen ground becomes too hard to drill. In warmer weather, the Arctic permafrost can thaw and machinery can become unstable and damage the environment.
     
    Race for the Arctic
    Almost all Arctic nations are scrambling to assert authority over the rich resources of the Arctic. This diplomatic conflict has been nicknamed the “New Cold War” or simply the “Race for the Arctic.”
     
    The exclusive economic zones of Russia, Norway, Denmark, Iceland, Greenland, Canada, and the United States extend to 200 nautical miles off their coasts. A country can explore and exploit all resources within its exclusive economic zone (EEZ)
     
    However, some Arctic nations are claiming territory on their continental shelves, not just their coastlines. Russia, Greenland, Denmark, and Canada, for instance, all claim the Lomonosov Ridge. The Lomonosov Ridge is an undersea mountain chain that stretches from the Canadian Arctic, through the North Pole, all the way to the waters off Siberia.
     
    Changing Climate in the Arctic
     
    Climate change is radically redefining the geography, biodiversity, and political units of the Arctic. 
     
    The extent of sea ice in the Arctic is shrinking. The 21st century has marked record lows in both the winter maximum and summer minimum extent of sea ice. Most climatologists estimate that by the year 2100, most Arctic sea ice will melt every summer. 
     
    The “twilight of the Arctic ice” would devastate many habitats. The plight of polar bears, for example, has become a symbol of global warming in the Arctic due to the cascading impacts of sea ice loss.
     
    Without sea ice, polar bears cannot catch enough seals to survive their annual winter fast. Polar bears that do survive are less likely to produce healthy offspring, reducing the population over generations. Scarcer food sources also drive polar bears into more contact with human populations, often relying on trash heaps for nutrition. This food sources impacts the health of polar bears and increases the incidents of conflict with human communities in the Arctic.
     
    The species range of the polar bear is also altered by climate change. Logic might indicate that polar bears would migrate further north as their traditional range heats up. Currents carry sea ice south, however, as it breaks up. Polar bears follow the sea ice habitat, and so their range has actually drifted south. This has brought polar bears into even closer contact with human populations, as well as prey species that have not adapted to the bears’ predatory behavior.
     
    The increasingly shrinking Arctic sea ice provides clear shipping routes for trade and travel. The Northwest Passage is still the most lucrative shipping lane in the Arctic. Experts estimate that shipping time may be cut by 40% if the Northwest and Northeast passages were ice-free all year. These deep-water shipping lanes also allow for larger, heavier ships than the Panama Canal, which would increase trade and profit even further.
     
    The tourism industry could also benefit from shrinking sea ice. In 2016, a luxury cruise ship traveled through the Northwest Passage for the first time. The ship, filled with more than 1,500 tourists, made the journey in three weeks.
    Arctic
    The Arctic is dominated by the Arctic ocean basin.
    Oil in ANWR 
    The Arctic National Wildlife Refuge (ANWR), situated on Alaska’s northeastern coast, is the largest protected wilderness in the United States. Extractive activities are allowed in the refuge, as long as the U.S. Congress approves. Some geologists estimate that there may be between 5 billion and 16 billion barrels of oil and natural gas beneath the coastal plain of the refuge. People have debated since the 1970s about whether to develop this pristine area, but Congress has not given any approval to drill or mine there.
    Icebreakers
    Travel in the Arctic is still dependent on icebreakers. An icebreaker is a very powerful ship capable of breaking up kilometers of sea ice, sometimes several meters thick. Icebreakers are most often powered by nuclear fuel, but can also run on gas and steam. They can be uncomfortable to travel in, as their shape allows them to roll back and forth more easily than other heavy ships. Russia manufactures the most powerful icebreakers.
    Balmy Arctic
    The Arctic is mostly an ocean surrounded by land. The Antarctic is mostly land surrounded by water. Because the Arctic ocean absorbs so much more solar radiation than the Antarctic ice sheet, the Arctic is much, much, much warmer than the Antarctic. In fact, the Arctic is not even the coldest place in the Northern Hemisphere. (The icy, subarctic interior of Siberia, in eastern Russia, holds that record.)
  • Term Part of Speech Definition Encyclopedic Entry
    albedo Noun

    scientific measurement of the amount of sunlight that is reflected by a surface.

    albedo Noun

    scientific measurement of the amount of sunlight that is reflected by a surface.

    algae Plural Noun

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

    apex predator Noun

    species at the top of the food chain, with no predators of its own. Also called an alpha predator or top predator.

    archipelago Noun

    a group of closely scattered islands in a large body of water.

    Encyclopedic Entry: archipelago
    Arctic Noun

    region at Earth's extreme north, encompassed by the Arctic Circle.

    Encyclopedic Entry: Arctic
    Arctic Circle Noun

    paralell of latitude that runs 66.5 degrees north of the Equator.

    assert Verb to state with confidence.
    autotroph Noun

    organism that can produce its own food and nutrients from chemicals in the atmosphere, usually through photosynthesis or chemosynthesis.

    Encyclopedic Entry: autotroph
    axis Noun

    an invisible line around which an object spins.

    Encyclopedic Entry: axis
    baleen noun, plural noun

    flexible, horn-like substance hanging from the upper jaw of certain whales, used to strain plankton from seawater when feeding.

    biodiversity Noun

    all the different kinds of living organisms within a given area.

    Encyclopedic Entry: biodiversity
    boreal forest Noun

    land covered by evergreen trees in cool, northern latitudes. Also called taiga.

    cabin Noun

    area in a vehicle where crew or passengers live.

    camouflage Verb

    to hide or disguise by blending in to surroundings. Also called cryptic coloration.

    carnivore Noun

    organism that eats meat.

    Encyclopedic Entry: carnivore
    cascade Verb to fall downward quickly and in great quantity.
    climate Noun

    all weather conditions for a given location over a period of time.

    Encyclopedic Entry: climate
    climate change Noun

    gradual changes in all the interconnected weather elements on our planet.

    Encyclopedic Entry: Earth's Changing Climate
    climatologist Noun

    person who studies long-term patterns in weather.

    colonize Verb

    to establish control of a foreign land and culture.

    conflict Noun

    a disagreement or fight, usually over ideas or procedures.

    contemporary Adjective

    having to do with the present time period.

    continental shelf Noun

    part of a continent that extends underwater to the deep-ocean floor.

    Encyclopedic Entry: continental shelf
    crucial Adjective

    very important.

    culture Noun

    learned behavior of people, including their languages, belief systems, social structures, institutions, and material goods.

    decay Verb

    to rot or decompose.

    decomposer Noun

    organism that breaks down dead organic material.

    devastate Verb

    to destroy.

    diet Noun

    foods eaten by a specific group of people or other organisms.

    Encyclopedic Entry: diet
    diplomatic Adjective

    skillful and respectful in dealing with people or communities.

    driftwood Noun

    pieces of wood that have traveled on currents in a body of water and drifted on shore.

    drill Verb

    to make a hole using a rotating digging tool.

    elevate Verb

    to raise higher than the surrounding area.

    elusive Adjective

    difficult to capture.

    engineer Noun

    person who plans the building of things, such as structures (construction engineer) or substances (chemical engineer).

    enormous Adjective

    very large.

    Equator Noun

    imaginary line around the Earth, another planet, or star running east-west, 0 degrees latitude.

    Encyclopedic Entry: equator
    equinox Noun

    period in which daylight and darkness are nearly equal. There are two equinoxes a year.

    Encyclopedic Entry: equinox
    evaporation Noun

    process by which liquid water becomes water vapor.

    Encyclopedic Entry: evaporation
    exclusive economic zone (EEZ) Noun

    zone extending 200 nautical miles off a country's coast. A country has the right to explore and exploit the living and nonliving things in its EEZ.

    exploit Verb

    to use or take advantage of for profit.

    exploration Noun

    study and investigation of unknown places, concepts, or issues.

    export Noun

    good or service traded to another area.

    fast Verb

    to not eat.

    fjord Noun

    long, narrow ocean inlet between steep slopes.

    Encyclopedic Entry: fjord
    food web Noun

    all related food chains in an ecosystem. Also called a food cycle.

    Encyclopedic Entry: food web
    forest Noun

    ecosystem filled with trees and underbrush.

    freshwater Noun

    water that is not salty.

    gem Noun

    mineral, rock, or organic material that can be cut and polished for use in jewelry.

    generation Noun

    group in a species made up of members that are roughly the same age.

    geographer Noun

    person who studies places and the relationships between people and their environments.

    glacier Noun

    mass of ice that moves slowly over land.

    Encyclopedic Entry: glacier
    global warming Noun

    increase in the average temperature of the Earth's air and oceans.

    Encyclopedic Entry: The Greenhouse Effect and our Planet
    habitat Noun

    environment where an organism lives throughout the year or for shorter periods of time.

    Encyclopedic Entry: habitat
    hazard Noun

    danger or risk.

    herbivore Noun

    organism that eats mainly plants and other producers.

    Encyclopedic Entry: herbivore
    hide Noun

    leather skin of an animal.

    iceberg Noun

    large chunks of ice that break off from glaciers and float in the ocean.

    Encyclopedic Entry: iceberg
    ice floe Noun

    floating chunk of frozen water less than 10 kilometers (6.2 miles) wide.

    ice sheet Noun

    thick layer of glacial ice that covers a large area of land.

    Encyclopedic Entry: ice sheet
    iconic Adjective

    event or symbol representing a belief, nation, or community.

    igloo Noun dome-shaped hut built of blocks of ice. Also called an ice house.
    incident Noun

    event or happening.

    indicate Verb

    to display or show.

    indigenous people Noun

    ethnic group that has lived in the same region for all of their known history.

    influx Noun

    entry or inflow.

    innovative Adjective

    new, advanced, or original.

    insulate Verb

    to cover with material to prevent the escape of energy (such as heat) or sound.

    international organization Noun

    unit made up of governments or groups in different countries, usually for a specific purpose.

    Encyclopedic Entry: international organization
    island Noun

    body of land surrounded by water.

    Encyclopedic Entry: island
    isolate Verb

    to set one thing or organism apart from others.

    landscape Noun

    the geographic features of a region.

    Encyclopedic Entry: landscape
    latitude Noun

    distance north or south of the Equator, measured in degrees.

    Encyclopedic Entry: latitude
    lichen Noun

    organism composed of a fungus or fungi and an alga or cyanobacterium.

    lucrative Adjective

    profitable or money-making.

    lumber Noun

    precisely cut pieces of wood such as boards or planks.

    luxury Noun

    expensive item.

    machinery Noun

    mechanical appliances or tools used in manufacturing.

    marine ecosystem Noun

    community of living and nonliving things in the ocean.

    microscopic Adjective

    very small.

    migrate Verb

    to move from one place or activity to another.

    mine Verb

    to extract minerals from the Earth.

    mineral Noun

    inorganic material that has a characteristic chemical composition and specific crystal structure.

    molt Verb

    to shed fur, skin, feathers, or other body covering.

    moss Noun

    tiny plant usually found in moist, shady areas.

    mountain range Noun

    series or chain of mountains that are close together.

    mouth Noun

    place where a river empties its water. Usually rivers enter another body of water at their mouths.

    Encyclopedic Entry: mouth
    native corporations Noun

    business organizations concerned with economic decisions for a region of Alaska in which native Alaskans own all the stock. Also called ANCSA corporations, after the 1971 law that created these units, the Alaska Native Claims Settlement Act.

    natural gas Noun

    type of fossil fuel made up mostly of the gas methane.

    Encyclopedic Entry: natural gas
    natural resource Noun

    a material that humans take from the natural environment to survive, to satisfy their needs, or to trade with others.

    navigate Verb

    to plan and direct the course of a journey.

    nomadic Adjective

    having to do with a way of life lacking permanent settlement.

    Northern Hemisphere Noun

    half of the Earth between the North Pole and the Equator.

    North Pole Noun

    fixed point that, along with the South Pole, forms the axis on which the Earth spins.

    Encyclopedic Entry: North Pole
    Northwest Passage Noun

    waterway connecting the Atlantic and Pacific Oceans.

    nutrient Noun

    substance an organism needs for energy, growth, and life.

    Encyclopedic Entry: nutrient
    nutrition Noun

    process by which living organisms obtain food or nutrients, and use it for growth.

    ocean basin Noun

    depression in the Earth's surface located entirely beneath the ocean.

    ocean current Noun

    continuous, predictable, directional movement of seawater.

    offspring Noun

    the children of a person or animal.

    oil Noun

    fossil fuel formed from the remains of marine plants and animals. Also known as petroleum or crude oil.

    oil barrel Noun

    unit of measurement for oil and other petroleum products in the United States equal to 159 liters or 42 gallons. Abbreviated bbl.

    ore Noun

    deposit in the Earth of minerals containing valuable metal.

    Encyclopedic Entry: ore
    organism Noun

    living or once-living thing.

    peninsula Noun

    piece of land jutting into a body of water.

    Encyclopedic Entry: peninsula
    permafrost Noun

    permanently frozen layer of the Earth's surface.

    Encyclopedic Entry: permafrost
    petroleum Noun

    fossil fuel formed from the remains of ancient organisms. Also called crude oil.

    phytoplankton Noun

    microscopic organism that lives in the ocean and can convert light energy to chemical energy through photosynthesis.

    pinniped Noun

    marine mammals that also live on land and have flippers, such as seals.

    plateau Noun

    large region that is higher than the surrounding area and relatively flat.

    Encyclopedic Entry: plateau
    precipitation Noun

    all forms in which water falls to Earth from the atmosphere.

    Encyclopedic Entry: precipitation
    predatory Adjective

    killing other animals for food.

    prey Verb

    to target, victimize, or devour.

    primary consumer Noun

    organism that eats plants or other autotrophs.

    profit Noun

    money earned after production costs and taxes are subtracted.

    pursuit Noun effort to secure or obtain.
    raptor Noun

    bird of prey, or carnivorous bird.

    rare earth element Noun

    one of 17 closely related metallic elements that occur together in nature and are difficult ot separate from each other.

    rely Verb

    to depend on.

    revolution Noun

    orbit, or a complete journey of an object around a more massive object.

    river valley Noun

    depression in the earth caused by a river eroding the surrounding soil.

    Roald Amundsen Noun

    (1872-1928) Norwegian explorer of the Arctic and Antarctic.

    route Noun

    path or way.

    Sami Noun

    people and culture native to northern Scandinavia.

    Scandinavia Noun

    region and name for some countries in Northern Europe: Iceland, Norway, Sweden, Finland, and Denmark.

    scavenger Noun

    organism that eats dead or rotting biomass, such as animal flesh or plant material.

    Encyclopedic Entry: scavenger
    sea ice Noun

    frozen ocean water.

    secondary consumer Noun

    organism that eats meat.

    sedge Noun

    grass-like plant native to wetlands.

    shipping channel Noun

    deep waterway where large boats regularly transport goods and people.

    shipping route Noun

    path in a body of water used for trade.

    Siberia Noun

    region of land stretching across Russia from the Ural Mountains to the Pacific Ocean.

    solar radiation Noun

    light and heat from the sun.

    solstice Noun

    astronomical event that occurs twice a year, when the sun appears directly overhead to observers at the Tropic of Cancer or the Tropic of Capricorn.

    Encyclopedic Entry: solstice
    sophisticated Adjective

    knowledgeable or complex.

    sovereignty Noun

    power or independence within a region.

    species range Noun

    native, geographic area in which an organism can be found. Range also refers to the geographic distribution of a particular species.

    Encyclopedic Entry: species range
    stilt Noun pole or post supporting a structure above the ground or water.
    storehouse Noun building where supplies are kept.
    structural engineering Verb

    study of the analysis and construction of structures, especially buildings.

    taiga Noun

    evergreen forest in cool, northern latitudes. Also called boreal forest.

    Encyclopedic Entry: taiga
    temperature Noun

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

    Encyclopedic Entry: temperature
    temporary Adjective

    not lasting or permanent.

    territory Noun

    land an animal, human, or government protects from intruders.

    tertiary consumer Noun

    carnivore that mostly eats other carnivores.

    textile Noun

    cloth or other woven fabric.

    thaw Verb

    to melt, or turn from ice to liquid.

    thermohaline circulation Noun

    ocean conveyor belt system in which water moves between the cold depths and warm surface in oceans throughout the world.

    thrive Verb

    to develop and be successful.

    tourism Noun

    the industry (including food, hotels, and entertainment) of traveling for pleasure.

    trade Noun

    buying, selling, or exchanging of goods and services.

    travel Noun

    movement from one place to another.

    tundra Noun

    cold, treeless region in Arctic and Antarctic climates.

    valuable Adjective

    worth a considerable amount of money or esteem.

    vegetation Noun

    all the plant life of a specific place.

    vermin Noun small animals that are destructive, annoying, and difficult to control.
    vibrant Adjective

    lively.

    Viking Noun

    seafaring people and culture native to Scandinavia between the 7th and 12th centuries.

    voyage Noun

    long journey or trip.

    weather Noun

    state of the atmosphere, including temperature, atmospheric pressure, wind, humidity, precipitation, and cloudiness.

    Encyclopedic Entry: weather
    weatherization Noun practice of protecting a building and its interior from the effects of sunlight, precipitation, and wind.