Encyclopedic Entry

Tea is harvested in the tropical foothills of Mount Kenya, Kenya.

Photograph by George F. Mobley

Quotable Twain
The famous author Mark Twain described the difference between weather and climate like this: "Climate is what we expect, weather is what we get."

The Big Chill
Antarcticas frigid climate makes it the only continent on Earth with no permanent human residents. The coldest temperature ever recordedminus-89.2 degrees Celsius (-128.5 degrees Fahrenheit)was at Vostok Station, Antarctica.

Climate is the long-term pattern of weather in a particular area. Weather is the state of the atmosphere over short periods of time. Weather can change from hour to hour, day to day, month to month or even year to year. A region’s weather patterns, tracked for more than 30 years, are considered its climate.

Climate Features

Different parts of the world have different climates. Some parts of the world are hot and rainy nearly every day. They have a tropical wet climate. Others are cold and snow-covered most of the year. They have a polar climate. Between the icy poles and the steamy tropics are many other climates that help make the Earth a unique planet.

Average temperature and precipitation are important features of a climate. So are the day-to-day, day-to-night, and seasonal variations in temperature and precipitation. For example, San Francisco, California, and Beijing, China, have similar yearly temperatures and precipitation. However, the daily and seasonal changes make San Francisco and Beijing very different. San Francisco’s winters are not much cooler than its summers, while Beijing is hot in summer and cold in winter. San Francisco’s summers are dry and its winters are wet. The wet and dry seasons are reversed in Beijing—it has rainy summers and dry winters.

Climate features also include windiness, humidity, cloud cover, and fogginess.

Climate Conditions

A region’s climate is something like a person’s personality. It is usually constant, but there may be surprises. Just as someone with a cheerful attitude will sometimes become sad, an area with a generally mild climate will occasionally experience extreme rainfall or drought. But because climates are mostly constant, living things can adapt to them.

The enormous variety of life on Earth is largely due to the variety of climates that exist and the climate changes that have occurred in the past.

Climate has influenced the development of cultures and civilizations. People everywhere have adapted in various ways to the climates in which they live.

Clothing, for example, is influenced by climate. The warm clothing developed by Eskimo cultures of Asia and North America are necessary for survival in the cold, windy climate near the North Pole. Grass skirts, on the other hand, are part of many cultures in warm, humid climates, such as Tahiti, an island in the South Pacific Ocean.


Climate also influences where and when a civilization constructs housing or other buildings. The ancient Anasazi people of southern North America built apartments into tall cliffs. The sheltered, shady area kept residents cool in the hot, dry desert climate. 

The development of agriculture was very dependent on climate. Ancient agricultural civilizations, such as those in Greece and India, flourished where the climate was mild. Communities could grow crops every season, and experiment with different types of foods and farming techniques.

Today, farmers are still in tune with the climate. They plant certain crops according to the expected amount of rainfall and the length of the growing season. A growing season is the time between the last frost of spring and the first frost of autumn. When the weather does not follow the typical climate pattern, it can mean hard times for farmers and higher food costs for consumers.

Of course, no climate is uniform. Small variations, called microclimates, exist in every climate region. Most are caused by topographic features such as lakes, vegetation, and cities. In large urban areas, for example, streets and buildings absorb heat from the sun, raising the average temperature of the city higher than the average temperatures of more open areas nearby. This is known as the “urban heat island effect.”

Large bodies of water, like the Great Lakes in the United States and Canada, can also have microclimates. Cities on the southern side of Lake Ontario, for example, are cloudier and receive much more snow than cities on the northern shore. This “lake effect” is a result of cold winds blowing across warmer lake water.

Climate Types

The most widely used system for classifying climates was proposed in 1900 by Wladimir Koppen. Koppen observed that the type of vegetation in a region depended largely on climate. He used this fact as the starting point for his classification scheme. Studying temperature and precipitation data, he and other scientists developed a system for naming climate regions.

According to this system, there are five climate groups: tropical, dry, mild, continental, and polar. These climate groups are further divided into climate types. The following list shows the climate groups and their types:

  • Tropical
  • Dry
    • Arid
    • Semiarid
  • Mild
    • Mediterranean
    • Humid subtropical
    • Marine
  • Continental
    • Warm summer
    • Cool summer
    • Subarctic (or boreal)
  • Polar
    • Tundra
    • Ice cap

 

All climates are the product of many factors, including latitude, elevation, topography, distance from the ocean, and location on a continent. The rainy tropical climate of West Africa, for example, results from the region’s location near the Equator and its position on the western side of the continent. A constant amount of sunlight keeps temperatures in the area warm and steady. West Africa is also at the site where moist trade winds meet, an area called the intertropical convergence zone (ITCZ) (pronounced “itch”). As a result, the region’s climate is warm and rainy.

Tropical Climates

There are three climate types in the tropical group: tropical wet; tropical monsoon; and tropical wet and dry.

Places with a tropical wet climate are also known as rain forests. Rain forests have the most predictable weather on Earth, with warm temperatures and regular rainfall. Annual rainfall exceeds 150 centimeters (59 inches), and the temperature varies more during a day than it does over a year. The coolest temperature, about 20-23 degrees Celsius (68-73 degrees Fahrenheit), occurs just before dawn. Afternoon temperatures usually reach 30-33 degrees Celsius (86-91 degrees Fahrenheit). Rain forests experience very little seasonal change, meaning average monthly temperatures remain fairly constant.

Tropical wet climates exist in a band extending about 10 degrees of latitude on either side of the Equator. This part of the globe is always under the influence of the intertropical convergence zone. The zone follows a pendulum-like path during the course of a year, moving back and forth across the Equator with the seasons. It moves north during summer in the Northern Hemisphere, and south during the northern winter.

Some tropical wet climates are wet throughout the year. Others experience more rainfall during the summer or winter, but they never have especially dry seasons. The U.S. state of Hawaii; Kuala Lumpur, Malaysia; and Belém, Brazil, are examples of areas with tropical wet climates.


Tropical monsoon climates are most common in southern Asia and West Africa. A monsoon is a wind system that reverses its direction every six months. They usually flow from sea to land in the summer, and from land to sea in the winter.

Summer monsoons bring large amounts of rainfall to tropical monsoon regions. People living in these regions depend on the seasonal rains to bring water to their crops. India and Bangladesh are famous for their monsoon climate patterns.

The third type of climate, tropical wet and dry climate, has three seasons. These areas are just outside the ITCZ, near the Equator. One season is cool and dry when the warm, moist ITCZ is in the opposite hemisphere. Another season is hot and dry as the ITCZ approaches. The last season is hot and wet as the ITCZ arrives and the region experiences months as a tropical wet climate.

Life in these tropical wet and dry regions depends on the wet season’s rains. During years when rains are light, people and animals suffer. Havana, Cuba; Kolkata, India; and Africa’s vast Serengeti Plain are in the wet and dry tropics.


Dry Climates

Regions lying within the dry climate group occur where precipitation is low, including cool, high latitudes. There are two dry climate types: arid and semiarid. Most arid climates receive 10 to 30 centimeters (4-12 inches) of rain each year, and semiarid climates receive enough to support extensive grasslands. Often, these grasslands are known as savannas or prairies.

Temperatures in both arid and semiarid climates show large daily and seasonal variations. The hottest spots in the world are in arid climates. The temperature in the North African town of El Aziza, Libya, reached 58 degrees Celsius (136 degrees Fahrenheit) on September 13, 1922—the highest weather temperature ever recorded.


Although rainfall is limited in all dry climates, there are few parts of the world where it never rains. One of the driest places on Earth is the Atacama Desert of Chile, on the west coast of South America. There, the town of Arica averages less than 0.05 centimeters (0.02 inches) of rain a year.

Semiarid regions, such as the Australian Outback, usually receive between 25 and 50 centimeters (10-20 inches) of rainfall every year. They are often located between arid and tropical climate regions.

Arid and semiarid climates can occur when warm, moist air is blocked by mountains. Denver, Colorado, next to the Rocky Mountains in the U.S., has this type of dry climate.

Mild Climates

Regions with mild and continental climates are also called temperate regions. Both climate types have distinct cold seasons. In these parts of the world, climate is influenced mostly by latitude and by a region’s position on the continent.

The mild climate type called Mediterranean climate has a warm summer and a short, mild, and rainy winter. It is found on the west coasts of continents between 30 and 40 degrees latitude, and along the shores of the Mediterranean Sea. Mediterranean summers feature clear skies, cool nights, and little rain. The city of Jerusalem, Israel, once had no rain in July for more than 100 years.

The type of mild climate known as humid subtropical climate is usually found on the eastern sides of continents. In cities such as Savannah, Georgia, in the U.S.; Shanghai, China; and Sydney, Australia, summers are hot and humid. Winter can be severely cold. Precipitation is spread evenly through the year and totals 76 to 165 centimeters (30-65 inches). Hurricanes and other violent storms are common in these regions.

Weather on both sides of a continent generally becomes cooler as latitude increases and areas are closer to the poles. The marine west coast climate, a type of mild climate typical of cities such as Seattle, Washington, in the U.S. and Wellington, New Zealand, has a longer, cooler winter than the Mediterranean climate. Drizzle falls about two-thirds of winter days, and temperatures average about 5 degrees Celsius (41 degrees Fahrenheit).


Continental Climates

Areas with continental climates have colder winters, longer-lasting snow, and shorter growing seasons. They are the transition zones between mild and polar climates. Continental climates experience extreme seasonal changes.

There are three types of continental climate—warm summer, cool summer, and subarctic. All these climates exist only in the Northern Hemisphere. Usually, continental climates are found in the interior of continents.

Warm summer climate regions often have wet summer seasons, similar to monsoon climates. For this reason, this climate type is also called humid continental. Most of Eastern Europe, including Romania and Georgia, has humid continental climates.

Cool summer climates have winters with low temperatures and snow. Cold winds, sweeping in from the Arctic, dominate the winter weather. People living in these climates have grown accustomed to the harsh weather, but those unprepared for such cold may suffer. Many of Napoleon Bonaparte’s soldiers, for example, were used to the mild Mediterranean climates of France. Thousands died in bitter cold as they retreated from Russia’s cool summer climate in the winter of 1812.

North of regions with cool summer climates are regions with subarctic climates. These regions, including northern Scandinavia and Siberia, experience very long, cold winters with little precipitation. Subarctic climates are also called boreal climates or taiga.

The range of weather in continental climate regions makes them among the most spectacular sites for weather phenomena. In autumn, for instance, vast forests put on their annual show of brilliant color before shedding their leaves as winter approaches. Thunderstorms and tornadoes, among the most powerful forces in nature, form mostly in continental climates.


Polar Climates

The two polar climate types, tundra and ice cap, lie within the Arctic and Antarctic Circles near the North and South Poles.

In tundra climates, summers are short, but plants and animals are plentiful. Temperatures can average as high as 10 degrees Celsius (50 degrees Fahrenheit) in July. Wildflowers dot the landscape, and flocks of birds return from their winter migrations to feed on insects and fish. Whales feed on microscopic creatures in the region’s cold, nutrient-rich waters. People have adapted to life on the tundra for thousands of years.

Few living things exist in the ice cap climates of the Arctic and Antarctic. Temperatures rarely rise above freezing, even in summer. The ever-present ice helps keep the weather cold by reflecting most of the sun’s energy back into the atmosphere. Skies are mostly clear and precipitation is low all year. In fact, Antarctica, covered by an ice cap a mile thick, is actually one of the largest, driest deserts on Earth.

High Elevation Climates

Several geographers and climatologists have modified the Köppen classification system over the years, including geographer Glen Trewartha, who added a category for highland climates.

There are two high elevation climate types: upland and highland. Upland climates occur on high plateaus, or flat-topped mountains. The Patagonian Plateau, in southern South America, has an upland high-elevation climate. Highland climates occur on mountains.

High-elevation climates are marked by very different temperatures and levels of precipitation. Climbing a lofty mountain or reaching a plateau can be like moving toward the poles. On some mountains, such as Mount Kilimanjaro, Tanzania, the climate is tropical at the base and polar at the summit. Often, high-elevation climate differs from one side of the mountain to the other.


Changes in Climate

Climate does not change from day to day like weather, but it does change over time. Climate changes happen slowly over hundreds or even thousands of years. For example, periodic ice ages have covered large portions of Earth with ice caps. Some evidence shows that the Sahara Desert was once covered by ocean during a warm “wet age.”

Climate change can happen for many reasons. The movement of tectonic plates, volcanic activity, and the tilt of Earth’s axis all have effects on climate. After the eruption of the island volcano of Krakatoa, Indonesia, in 1883, winters and even summers in Asia and Europe were colder and darker. Volcanic ash blocked the sun. Farmers had to adjust to shorter, weaker growing seasons. Climates around the world were changed for years.

More recently, human civilizations have begun to affect climate. Human activities that include burning fossil fuels and cutting down forests release greenhouse gases into the atmosphere. These gases hold in heat, which raises temperature. Scientists believe this “greenhouse effect” is increasing global temperatures.

Increasing temperatures can change climate types. Low-lying islands may be flooded as sea waters rise from melting glaciers. Heat in the atmosphere may increase the interaction of diverse weather systems, resulting in more hurricanes and typhoons. Organisms that have adapted to one climate may have to migrate or adapt to warmer temperatures. Manatees, for instance, are marine mammals native to tropical waters. As temperatures increase, manatees have been migrating as far north as New York City, New York.

 

Vocabulary

Term Part of Speech Definition Encyclopedic Entry

absorb

Verb

to soak up.

accustom

Verb

to get used to.

adapt

Verb

to adjust to new surroundings or a new situation.

agriculture

Noun

the art and science of cultivating the land for growing crops (farming) or raising livestock (ranching).

Encyclopedic Entry: agriculture

Anasazi

Noun

(1200 BCE-1300 CE) people and culture native to what is now the southwestern United States. Also called Ancestral Puebloans.

ancient

Adjective

very old.

Arctic

Noun

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

Encyclopedic Entry: Arctic

arid climate

Noun

(dry climate) region that receives 10 to 30 centimeters (4-12 inches) of rain each year.

atmosphere

Noun

layers of gases surrounding a planet or other celestial body.

Encyclopedic Entry: atmosphere

axis

Noun

an invisible line around which an object spins.

Encyclopedic Entry: axis

bitter

Adjective

harsh.

boreal climate

Adjective

region that experiences long, cold winters with very little precipitation. Also called a subarctic or tundra climate.

city

Noun

large settlement with a high population density.

civilization

Noun

complex way of life that developed as humans began to develop urban settlements.

Encyclopedic Entry: civilization

classify

Verb

to identify or arrange by specific type or characteristic.

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: climate change

climate group

Noun

one of five classifications of the Earth's climates: tropical, dry, mild, continental, and polar.

climate type

Noun

division within a climate group.

climatologist

Noun

person who studies long-term patterns in weather.

cloud cover

Noun

amount of sky covered with clouds.

construct

Verb

to build or erect.

consumer

Noun

person who uses a good or service.

continent

Noun

one of the seven main land masses on Earth.

Encyclopedic Entry: continent

continental climate

Noun

climate group that experiences extreme seasonal change. Continental climates are only found in the Northern Hemisphere.

cool summer climate

Noun

region that experience cool summers and snowy winters.

crop

Noun

agricultural produce.

Encyclopedic Entry: crop

culture

Noun

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

data

Plural Noun

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

dependent

Adjective

relying on or needing something.

desert

Noun

area of land that receives no more than 25 centimeters (10 inches) of precipitation a year.

Encyclopedic Entry: desert

development

Noun

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

diverse

Adjective

varied or having many different types.

dominate

Verb

to overpower or control.

drought

Noun

period of greatly reduced precipitation.

Encyclopedic Entry: drought

dry season

Noun

time of year with little precipitation.

elevation

Noun

height above or below sea level.

Encyclopedic Entry: elevation

enormous

Adjective

very large.

Equator

Noun

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

Encyclopedic Entry: equator

eruption

Noun

release of material from an opening in the Earth's crust.

Eskimo

Noun

people and culture native to the Arctic region of eastern Russia, the U.S. state of Alaska, Canada, and Greenland.

experiment

Verb

to try or test an idea.

extensive

Adjective

very large.

farming

Noun

the art, science, and business of cultivating the land for growing crops.

flourish

Verb

to thrive or be successful.

fog

Noun

clouds at ground level.

Encyclopedic Entry: fog

forest

Noun

ecosystem filled with trees and underbrush.

fossil fuel

Noun

coal, oil, or natural gas. Fossil fuels formed from the remains of ancient plants and animals.

frigid

Adjective

very cold.

frost

Noun

thin coat of ice covering objects when the dew point is below freezing.

Encyclopedic Entry: frost

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

grassland

Noun

ecosystem with large, flat areas of grasses.

Great Lakes

Noun

largest freshwater bodies in the world, located in the United States and Canada. Lake Huron, Lake Ontario, Lake Michigan, Lake Erie, and Lake Superior make up the Great Lakes.

greenhouse effect

Noun

phenomenon where gases allow sunlight to enter Earth's atmosphere but make it difficult for heat to escape.

Encyclopedic Entry: greenhouse effect

greenhouse gas

Noun

gas in the atmosphere, such as carbon dioxide, methane, water vapor, and ozone, that absorbs solar heat reflected by the surface of the Earth, warming the atmosphere.

growing season

Noun

period in the year when crops and other plants grow rapidly.

harsh

Adjective

extreme.

hemisphere

Noun

half of a sphere, or ball-shaped object.

Encyclopedic Entry: hemisphere

high-elevation climate

Noun

climate group found in mountains and plateaus.

highland climate

Noun

(high-elevation climate) region found on and around mountains.

housing

Noun

shelters where people live.

humid continental

Noun

(continental climate) region that experiences cold winters and warm, wet summers. Also called a warm summer climate.

humidity

Noun

amount of water vapor in the air.

Encyclopedic Entry: humidity

humid subtropical climate

Noun

region that experiences cool winters and hot humid summers.

hurricane

Noun

tropical storm with wind speeds of at least 119 kilometers (74 miles) per hour. Hurricanes are the same thing as typhoons, but usually located in the Atlantic Ocean region.

ice age

Noun

long period of cold climate where glaciers cover large parts of the Earth. The last ice age peaked about 20,000 years ago. Also called glacial age.

ice cap climate

Noun

region where temperatures rarely rise above freezing.

influence

Verb

to encourage or persuade a person or organization to act a certain way.

interaction

Noun

relationship between two or more forces, objects, or organisms.

Intertropical Convergence Zone (ITCZ)

Noun

belt of low-pressure air currents that circle the Earth at the Equator. Also known as the Monsoon Zone.

island

Noun

body of land surrounded by water.

Encyclopedic Entry: island

lake

Noun

body of water surrounded by land.

lake effect

Noun

process where cold winds blowing over a relatively warm lake cause rapid cloud formation and precipitation.

latitude

Noun

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

Encyclopedic Entry: latitude

manatee

Noun

threatened marine mammal native to the Caribbean Sea and Atlantic Ocean.

marine mammal

Noun

an animal that lives most of its life in the ocean but breathes air and gives birth to live young, such as whales and seals.

marine west coast climate

Noun

(mild climate) region that experiences rain and long, cool winters.

Mark Twain

Noun

(1835-1910, born Samuel Langhorne Clemens) American writer.

Mediterranean climate

Noun

(mild climate) region that experiences mild winters and warm summers.

microclimate

Noun

small area where the climate differs within a larger climate region, such as "heat islands" in a city.

microscopic

Adjective

very small.

migrate

Verb

to move from one place or activity to another.

migration

Noun

movement of a group of people or animals from one place to another.

mild climate

Noun

climate group that experiences seasonal temperature changes. Also called a temperate climate.

moist

Adjective

damp or slightly wet.

monsoon

Noun

seasonal change in the direction of the prevailing winds of a region. Monsoon usually refers to the winds of the Indian Ocean and South Asia, which often bring heavy rains.

Encyclopedic Entry: monsoon

mountain

Noun

landmass that forms as tectonic plates interact with each other.

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

nutrient

Noun

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

Encyclopedic Entry: nutrient

occasionally

Adverb

sometimes.

Outback

Noun

remote, sparsely populated interior region of Australia.

Patagonia

Noun

large plateau in southern South America, stretching from the Andes Mountains to the Atlantic Ocean.

pendulum

Noun

object suspended from a point, able to swing back and forth.

periodic

Adjective

occasional.

phenomena

Plural Noun

(singular: phenomenon) any observable occurrence or feature.

plateau

Noun

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

Encyclopedic Entry: plateau

polar

Adjective

having to do with the North and/or South Pole.

polar climate

Noun

climate group found within the Arctic and Antarctic Circles.

prairie

Noun

large grassland; usually associated with the Mississippi River Valley in the United States.

Encyclopedic Entry: prairie

precipitation

Noun

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

Encyclopedic Entry: precipitation

predictable

Adjective

regular or able to be forecasted.

rain forest

Noun

area of tall evergreen trees and a high amount of rainfall.

rainy season

Noun

time of year when most of the rain in a region falls.

region

Noun

any area on the Earth with one or more common characteristics. Regions are the basic units of geography.

Encyclopedic Entry: region

retreat

Verb

to go back to a familiar or safe place.

savanna

Noun

type of tropical grassland with scattered trees.

Scandinavia

Noun

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

scheme

Noun

structure or diagram of the way information is studied, documented, and understood.

seasonal

Adjective

likely to change with the seasons.

semiarid climate

Noun

(dry climate) region that receives between 25 and 50 centimeters (10-20 inches) of rainfall every year.

shore

Noun

coast.

Siberia

Noun

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

snow

Noun

precipitation made of ice crystals.

spectacular

Adjective

dramatic and impressive.

subarctic climate

Noun

region that experiences long, cold winters with very little precipitation. Also called a boreal or tundra climate.

sunlight

Noun

visible radiation from the sun.

taiga

Noun

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

Encyclopedic Entry: taiga

technique

Noun

method of doing something.

tectonic plate

Noun

large, moveable segment of the Earth's crust.

temperature

Noun

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

Encyclopedic Entry: temperature

thunderstorm

Noun

cloud that produces thunder and lightning, often accompanied by heavy rains.

topographic feature

Noun

map representation of the Earth's surface showing elevation.

topography

Noun

study of the shape of the surface features of an area.

tornado

Noun

a violently rotating column of air that forms at the bottom of a cloud and touches the ground.

trade wind

Noun

winds that blow toward the Equator, from northeast to southwest in the Northern Hemisphere and from southeast to northwest in the Southern Hemisphere.

transition zone

Noun

area between two natural or artificial regions.

tropical climate

Noun

climate group that experiences hot, wet summers.

tropical monsoon climate

Noun

region that experiences the monsoon winds, which bring heavy rain.

tropical wet and dry climate

Noun

region that experiences three seasons: cool, hot, and wet.

tropical wet climate

Noun

region that experiences hot temperatures and heavy rainfall all year. Also called a rain forest climate.

tundra climate

Noun

region that experiences short summers and long winters.

typhoon

Noun

tropical storm with wind speeds of at least 74 miles (119 kilometers) per hour. Typhoons are the same thing as hurricanes, but usually located in the Pacific or Indian Ocean region.

typical

Adjective

ordinary.

uniform

Adjective

exactly the same in some way.

unique

Adjective

one of a kind.

upland climate

Noun

(high-elevation climate) region found on and around large plateaus.

urban area

Noun

developed, densely populated area where most inhabitants have nonagricultural jobs.

Encyclopedic Entry: urban area

urban heat island

Noun

city area that is always warmer than the surrounding area.

Encyclopedic Entry: urban heat island

variation

Noun

difference.

vegetation

Noun

all the plant life of a specific place.

volcanic

Adjective

having to do with volcanoes.

volcanic ash

Noun

fragments of lava less than 2 millimeters across.

Encyclopedic Entry: volcanic ash

warm summer climate

Noun

region that experiences cool winters and warm, wet summers. Also called a humid continental climate.

weather

Noun

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

Encyclopedic Entry: weather

weather system

Noun

movement of warm or cold air.

wind

Noun

movement of air (from a high pressure zone to a low pressure zone) caused by the uneven heating of the Earth by the sun.

winter

Noun

time of year when part of the Earth receives the least daylight: December, January, and February in the Northern Hemisphere and June, July, and August in the Southern Hemisphere.

Wladimir Koppen

Noun

(1846-1940) Russian-German geographer and climatologist.

Credits

Media Credits

The audio, illustrations, photos, and videos are credited beneath the media asset, except for promotional images, which generally link to another page that contains the media credit. The Rights Holder for media is the person or group credited.

Writers

Joe Jaszewski
Hilary Costa
Andrew Turgeon
Tara Ramroop
Santani Teng
Audrey Carangelo
Melissa McDaniel
Erin Sprout
Diane Boudreau

Illustrators

Mary Crooks, National Geographic Society
Dinara Sagatova
Tim Gunther, Illustrator

Editors

Kara West
Jeff Hunt
Kim Rutledge
Jeannie Evers

Educator Reviewer

Nancy Wynne

Expert Reviewer

Lindsey Mohan, Ph.D.

Producer

Caryl-Sue, National Geographic Society

Sources

Dunn, Margery G. (Editor). (1989, 1993). "Exploring Your World: The Adventure of Geography." Washington, D.C.: National Geographic Society.

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