CLIMATE AND VEGETATION

CLIMATE

Climate is created by the sun’s solar energy interacting with the earth’s land, water, and air.

THE SEASONS

The seasons change b/c of the changing position of the earth in relation to the sun.

Weather extremes are related to location on earth.

THE EARTH’S TILT Earth is tilted at a 23.5˚ angle relative to the

sun Areas of Earth get more, less direct sun at

different times of year The seasons are related to the earth’s tilt

and revolution

SOLSTICE

The solstice marks the beginning of summer/winter. - sun’s rays directly overhead at noon at furthest points north and south

-Summer Solstice = longest day of the year

-Winter Solstice = shortest day It occurs on June 21/22 and

December 22/23

EQUINOX

The equinox marks the beginning of spring/fall (autumn).- day and night are equal in length

It occurs on September 23 and March 21.

WEATHER Weather is the

condition of the atmosphere at a particular location and time.

Climate is the term for weather over a long period of time.-Ex. Northern Russia

has a cold climate.

FACTORS THAT INFLUENCE WEATHER

Sun - amount of solar energy received

Water vapor – determines where there will be precipitation.

Cloud Cover – holds water vapor.- Precipitation —

water droplets falling as rain, snow, sleet, hail

MORE FACTORS Elevation – Higher

elevation = thinner air, loss of ability to hold moisture

Air movement (wind) – moves the solar energy and moisture (clouds) it holds.

Landforms and bodies of water Water heats/cools

slowlyLand heats/cools

rapidly

PRECIPITATIONPrecipitation comes about

when: 1. warm air rises, cools,

loses ability to hold water vapor2. water vapor condenses into droplets3. water droplets form clouds4. heavy clouds release droplets as rain, sleet, snow or hail

PRECIPITATION There are 3

types of precipitation:

1. Convectional2. Orographic3. Frontal

THE 3 TYPES

RAIN SHADOW

Land on the leeward side of hills and mountains.

There is little precipitation in the rain shadow.

HURRICANES!!!!

HURRICANE FORMATION Form over warm, tropical ocean

waters. Sometimes called typhoons (Asia) Formed when air flows over warm

water (over 80 degrees), picking up large amounts of moisture and energy.

This flows into a low pressure core & tightens to form the “eye” or center.

The more heat energy there is, the stronger the winds become.

HURRICANE CHARACTERISTICS

Forms slowly over days

10-20 mile wide eye

Can be up to 500 miles wide

Classified by wind speed in the Saffir-Simpson scale; category 1-5

Winds from 75-200 mph

Winds move counter-clockwise (northern hemisphere)

Most storms start off the coast of Africa and move west (Cape Verde storms)

Damage includes flooding, wind damage, & storm surge.

SAFFIR-SIMPSON SCALE

CAPE VERDE STORM

HURRICANE DAMAGE

HURRICANE ANDREW In 1992,

Hurricane Andrew, a category 5 hurricane made landfall in Florida.

At the time, it was the most costliest hurricane in history, causing over $26 billion in damages.

HURRICANE ANDREW

HURRICANE KATRINA Hurricane Katrina

was one of the most deadliest and devastating hurricanes in recorded history.

It was responsible for 1,800 deaths and over $81 billion in damages, making it the costliest natural disaster in U.S. history.

HURRICANE KATRINA

HURRICANE KATRINA

TORNADOES

TORNADOES Powerful funnel-shaped columns of

spiraling air. Warm air and cool air colliding create

them Winds up to 300 mph. Measured on the Fujita Scale; 0-6. Generally they have small diameters

(300 ft.) and travel short distances (1 mile)

3 out of 4 tornadoes in the world occur in the U.S. (around 700 per year)

FUJITA SCALE

F1 TornadoF2 Tornado

F3 Tornado F4 Tornado

FUJITA SCALE

F5 Tornado

JOPLIN, MISSOURI

On May 22, 2011 a catastrophic, multi-vortex F5 tornado hit the town of Joplin, Missouri.

It killed 158 people and caused nearly $3 billion in damages making it the deadliest and costliest tornado in American history.

JOPLIN, MISSOURI

Before

After

BLIZZARDS, DROUGHTS, FLOODS

Blizzard - Heavy snowstorm w/ winds of more than 35 mph creating reduced visibility.

Floods - Water spreads out over normally dry land

Droughts – A long period of time w/o rain or minimal rainfall.- Droughts result in crop failures,

reduced levels of water in storage.

STORM OF THE CENTURY In 1993, a massive storm

hit the United States. Known as the “White

Hurricane”, this storm not only caused a blizzard, but heavy winds, rains and tornadoes.

Many states received several feet of snow. Tennessee got the worst with over 5 ft. of snow in some areas!

In total, more than 300 people died as a result of this storm.

FLOODS

THE GREAT FLOOD OF 1993

In 1993 a great flood occurred in the Mississippi River basin.

The flood was among the most costly and devastating to ever occur in the United States, with $15 billion in damages and effecting over 30,000 square miles.

The floods claimed near 50 lives.

LANDSAT views of the Mississippi,Missouri and Illinois Rivers.

DROUGHT Drought is an

extended period of time when a region has a deficiency in its water supply whether surface or underground water.

A drought can last for months or years.

 It can cause significant damage[and harm on the ecosystem, agriculture of the affected region as well as damage to the economy.

DUST BOWL – 1930’S The Great Plains

(150,000 square mile region) was ravaged by drought.

Thousands of families were forced to flee and find work elsewhere.

Major contributor of the economic disaster known as the Great Depression that took over 10 years to recover from.

MORE FROM THE BOWL

MORE DUST

GHOST TOWN? In 2011, Texas was hit hard by

drought. The drought dried up areas so

much that in one town, it revealed some old history.

The city of Bluffton, Texas was purposefully flooded more 50 years ago to create Lake Buchanan.

Many parts of town were submerged under the 20-30 feet under the lake, that is, until the drought.

Since the drought, receding lakes have been revealing the foundations of buildings, streets and eerily, old gravesites…

CLIMATE Climate reflects

the seasonal patterns of weather for a location over a long period of time.

Global climatic changes may be natural or human-made.

4 FACTORS THAT INFLUENCE CLIMATE

1. Wind and Ocean Currents

2. Latitude 3. Elevation 4. Topography

WIND AND OCEAN CURRENTS Help distribute sun’s

heat. Convection – the

transfer of heat in the atmosphere by upward motion of the air.

Wind - created by cool air (high pressure) rushing into warm air (low pressure).

WIND PATTERNS Hot air moves toward

the poles, and cold air moves towards the equator.

Winds are curved b/c of earth’s rotation.

Coriolis effect – bending of the winds.

Winds are identified from the direction they come from.

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OCEAN CURRENTS Warm water flows away from the

equator toward the poles and vice versa.

Winds blowing over ocean currents affect the climate of lands.

Gulf Stream and North Atlantic Drift keep Europe moderate.

Europe is much more moderate than Canada.

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ZONES OF LATITUDE

There are three zones of latitude.

1. Low or tropical

2. Middle or temperate

3. High or polar

ELEVATION AND TOPOGRAPHY Temperature

drops 3.5 degrees for every 1,000 feet you climb.

Mountains can affect climate by not allowing clouds to pass over them.

What is this called?

CHANGES IN CLIMATE

El Nino – The natural warming of the waters off the coast of S. America. - Every 2-7 years, easterly winds change

directions ad push warm water w/ heavy rains towards the Americas.

La Nina – Reverse of El Nino. Causes drought conditions to occur along the Pacific coast.

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GLOBAL WARMING Since the 1800s, the temperature of the

earth has increased. Scientists estimate that the temp. will

increase 3.5 degrees in the next century.

Greenhouse effect- Gases released by coal and petro traps solar energy.

Scientists predict ice caps will melt and severe flooding could occur.

CLIMATE REGIONS Climate regions tell geographers about

an area without giving many local details.

Temperature and precipitation are the two most important factors.

5 General Regions: Tropical (low latitude), dry (arid), mid-latitude, high latitude, and highland.

TROPICAL WET Always hot Avg. temp. of 80 deg. F Central & South America Africa and Southwest Asia

HUMID SUBTROPICAL Long, hot and humid summers Mild to cool winters Found on east coast of continents Suitable or raising crops

MEDITERRANEAN Summers are hot and dry Winters are cool and wet

MARINE WEST COAST Moderate

temperatures frequently cloudy,

foggy, damp

SPARKLES, REALLY?

SEMIARID Receives little precipitation Hot summers Found in interior of continents, near

deserts

DESERT Categorized according to rainfall Can be hot or cold Receive less than 10 inches of rain/year

TUNDRA Flat, treeless lands around Arctic Circle Very little precipitation Mostly in Northern Hemisphere Permafrost – subsoil always frozen

ICE CAP Permanently freezing Rarely snows – too cold Called polar deserts

SOILS AND VEGETATION Soil and climate

help to determine the vegetation of a region.

Human land use alters the vegetation in both positive and negative ways.

SHAPING HUMAN EXISTENCE

Soil is a thin layer of weathered rock, humus, air, water

Topsoil refers to the top 6” of soil

Soil characteristics vary with climate

Type of soil determines type of vegetation that can be supported

Type of vegetation determines type of possible human activity.

NATURAL ENVIRONMENTS Ecosystem—

interdependent community of plants and animals

Biome—the ecosystem of a particular region

Biomes are further divided into: - forest - grassland - desert - tundra

FORESTS Forest regions categorized

by trees they support—broadleaf or needle

Deciduous—broadleaf trees: maple, oak, birch, cottonwood - mostly in Northern

Hemisphere Coniferous—needle leaf

trees; cone bearing: pine, fir, cedar - mostly in Northern

Hemisphere Deciduous and coniferous

trees together form mixed forest

WHICH TYPE OF FOREST?

FORESTS Rain forest—

tropical forest covered with broadleaf trees

GRASSLANDS Flat regions with

few trees A savanna is a

tropical grassland Steppe, or

prairie, are temperate grasslands of Northern Hemisphere

DESERT AND TUNDRA Plants in these

regions have adapted to climate extremes:

- tundra plants (mosses, lichen) hug the ground

- desert plants (cacti, sagebrush) conserve water, withstand heat

HUMAN IMPACT ON THE ENVIRONMENT

Humans either adapt to land, or alter it to meet their needs

Some human activities that affect the environment: - building dams - installing irrigation

systems - planting crops - slashing and

burning vegetation