PLANET EARTH EDITED BY MR BARKHAU WRITTEN BY

PLANET EARTH EDITED BY MR. BARKHAU WRITTEN BY: NOT MR. BARKHAU

OUR SOLAR SYSTEM • Earth is part of a large physical system containing countless objects, all of which revolve around the sun. • Eight spheres, called planets, are the largest objects in the solar system.

THE 4 SPHERES • Earth is made of four spheres: • atmosphere • hydrosphere • lithosphere • biosphere

HYDROSPHERE • Includes the liquid and frozen surface water • Groundwater • Water vapor in and around oceans, lakes, and rivers on Earth • 70% of earth’s surface

LITHOSPHERE • Land or surface areas on Earth • Including the continents, islands, and ocean basins • 30% of earth’s surface

ATMOSPHERE • The layer of gasses surrounding the earth: • protects Earth from radiation, space debris • 78% nitrogen, 21% oxygen

BIOSPHERE • The part of Earth that supports life for all: • People • Animals • Plants • Contains: atmosphere, lithosphere, and hydrosphere

OCEANIC LANDFORMS • The Continental Shelf is sea floor from continent’s edge to deep ocean • Sea floor has ridges, valleys, canyons, plains, mountain ranges

• Mt. Everest- 29, 028 ft • Dead Sea- 1, 312 ft below sea level

EARTH’S STRUCTURE • For millions of years, the surface of the Earth has been moving. • The Earth is composed of three layers • core at Earth’s center • mantle layer of dense rock on the outer core • crust forming Earth’s surface.

EARTH’S STRUCTURE • Many scientists believe Earth was once a single land mass called Pangaea, but… • Continental Drift slowly spread the continents apart.

EARTH’S STRUCTURE • Plate tectonics describes the activities of continental drift and magma flow • Referring to the physical processes that create and shape: • Continents • Islands • Oceans • Mountain Ranges

INTERNAL FORCES OF CHANGE • Mountains are formed when Earth’s giant continental and oceanic plates collide.

INTERNAL FORCES OF CHANGE • Moving plates sometimes cause Earth’s surface to buckle forming folds • Moving plates form cracks called faults.

INTERNAL FORCES OF CHANGE • Violent movements of Earth’s crust along fault lines are called earthquakes, which dramatically change the surface of the land the floor of the ocean.

INTERNAL FORCES OF CHANGE • Volcanoes are mountains formed by lava or magma that breaks Earth’s surface.

EXTERNAL FORCES OF CHANGE • Wind and water break down the Earth’s surface through weathering and erosion.

EXTERNAL FORCES OF CHANGE • Physical weathering happens when large masses of rock are broken down into smaller pieces.

EXTERNAL FORCES OF CHANGE • Glaciers are large bodies of ice that move across the Earth’s surface, changing the landscape as they flow.

MR. BARKHAU HIKED ACROSS PART OF VATNAJÖKULL GLACIER IN 2013

EXTERNAL FORCES OF CHANGE • Soil building takes thousands of years of weathering, erosion, and biological activity • Influenced by five factors: • Climate, topography, geology, biology and time

WATER

THE WATER CYCLE • Almost all of the hydrosphere is saltwater found in oceans, seas, and some lakes.

THE WATER CYCLE • The amount of water on Earth never changes, but it is constantly moving through the processes of evaporation, condensation, and precipitation.

THE WATER CYCLE • Evaporation is when the sun's energy causes water to change into vapor or gas.

THE WATER CYCLE • Condensation is an excess of water vapor that changes into liquid water after warm air cools.

THE WATER CYCLE • Precipitation is the release of moisture through rain, snow, or sleet.

BODIES OF SALT WATER • Seventy percent of the Earth’s surface is water, primarily salt water. • Salt water cannot be used for drinking, farming, or manufacturing.

BODIES OF SALT WATER • Due to a growing population and the need for more freshwater, some countries are focusing on the desalination process, which removes the salt from seawater.

BODIES OF SALT WATER • Desalination is expensive and is also controversial; critics believe the process has negative environmental and economic impacts.

BODIES OF FRESH WATER • Less than one-third of a percent of freshwater is found in lakes, rivers, and streams and their tributaries.

BODIES OF FRESH WATER • Aquifers and groundwater are important sources of freshwater found underground within the Earth.

EARTH –SUN RELATIONSHIPS AKA WEATHER

CLIMATE AND WEATHER • Weather is the condition of the atmosphere at a specific time. • What Causes the Weather? • Sun: solar energy • Water vapor: whether or not there will be precipitation (snow, sleet, hail)

CLIMATE AND WEATHER • Climate refers to the average weather conditions over many years • Earth's tilt on its axis in relation to the sun affects temperatures from day to night

CLIMATE AND WEATHER • Seasons and weather occur because of the changing position of the earth in relation to the sun. • Weather extremes are related to location on earth.

SEASONS AND WEATHER • The solstice marks the beginning of summer and winter • The equinox marks the beginning of spring and autumn

THE GREEN HOUSE EFFECT • The greenhouse effect allows trapped atmospheric gases to radiate heat that warms the Earth.

THE GREENHOUSE EFFECT • Under normal conditions, the atmosphere naturally provides enough insulation to promote life on Earth. • The radiation the Earth receives from the sun must equally balance with the heat radiated back into space to avoid temperature extremes in order to support life. • If not you get global warming

FACTORS AFFECTING CLIMATE

LATITUDE, CLIMATE, AND ELEVATION • Earth's rotation around the sun creates predictable climate patterns that correspond with latitude zones.

LATITUDE, CLIMATE, AND ELEVATION • The low latitudes include the area between the Tropics of Capricorn and Cancer, including the Equator • All receive nearly direct sunlight and have warm to hot climates

LATITUDE, ELEVATION, AND CLIMATE • The high latitudes include the polar zones, which generally have very cold climates.

LATITUDE, ELEVATION, AND CLIMATE • The mid-latitude zones between 30° and 60° experience variable weather with generally temperate climates. • Elevation influences climate at all latitudes

WIND • Winds occur when sunlight heats Earth's atmosphere and surface unevenly • wind movement is critical for distributing the sun's energy around the planet

OCEAN CURRENTS • Ocean currents also distribute energy

WIND AND WATER • Wind and water work together to affect weather, creating precipitation that both affects and is affected by temperature.

LANDFORMS AND CLIMATE • Climates are affected by the presence or absence of certain physical features, such as mountains or large bodies of water.

LANDFORMS AND CLIMATE • Large bodies of water are slower to heat and cool, so they help keep temperatures around them moderate. • Mountain ranges push air upward on the windward side, which cools and releases precipitation.

CLIMATE REGIONS AND BIOMES • Four climate zones: • • Tropical Dry Multi-latitude High-latitude

CLIMATE REGIONS AND BIOMES • Biome: ecological community defined by distinctive plant and animal groups.

CLIMATE REGIONS • Tropical climates are found in or near the low latitudes.

CLIMATE REGIONS • Dry climates are semi-arid (steppe) or arid (desert).

CLIMATE REGIONS • Midlatitude climates have variable weather patterns.

CLIMATE REGIONS • High-latitude climates have freezing temperatures all year.

CLIMATE CHANGE • Climate change: major changes in the climate over an extended period of time.

CLIMATE CHANGE • Indicators include: • • Rising global temperatures Severe weather changes Heat waves Severe weather events