Earth Systems, Resources, and the Environment

Chapter 1.1 & Chapter 25

Earth Science

Objectives section 1.1Name the four major branches of Earth ScienceDescribe what is studied in each of the major

branches of Earth ScienceList the major systems of the EarthGive examples and describe how the major systems

interrelate

Earth Science

Objectives section 1.1Understand how geochemical cycles relate to Earth

systemsDescribe the geochemical cycle for CarbonDescribe the geochemical cycle for Water

Earth Science

Earth Science includes four major branches:

Astronomy is the study of objects beyond Earth’s atmosphere

Meteorology is the study of the air surrounding the planet.

Earth Science

Earth Science includes four major branches:

Geology is the study of the materials that make up the Earth and the processes that form the Earth.

Oceanography is the study of the Earth’s oceans.

Earth Systems

Anything that happens to one thing on Earth affects everything else

We depend on the Earth (all the systems) for survival

Everything that we have is made from Earth materials with the input of energy from two sources.

The two major sources of energy on Earth are the Sun, and heat from Earth’s interior

Earth Systems

There are four major Earth systems:

Lithosphere – uppermost solid layer of the mantle and the crust (rides on the Asthenosphere)

Atmosphere – air that surrounds the Earth

Hydrosphere – All the water on Earth often called the Water cycle.

Biosphere – all living things on the Earth.

Earth Systems - Lithosphere

Earth Systems - Hydrosphere

Earth Systems

Earth scientists study how the four spheres are interrelated.

A system is a group of interacting parts that form a complex whole.

Earth Systems

Geochemical cycles – the Earth is essentially a closed system so there is a fixed amount of each element.

Each element cycles through the systems on Earth.

Often an element combines with other elements to form more complex compounds, or is broken down into simpler compounds.

For example: Carbon

Geochemical cycles

Carbon cycle:

How does carbon cycle through the four systems?

Geochemical cycles – Carbon C

Geochemical cycles

Water cycle:

How does water through the four systems?

Geochemical cycles – Water H2O

There are four major Earth systems:

25.1 What are resources?

25.1 ObjectivesDistinguish between renewable and non-renewable

resources Identify and understand how renewable and non-

renewable resources are distributed on Earth

25.1 What are Resources?

Natural resources include Earth’s air, water, land, and all living things.

Renewable resources are things on Earth that can be reproduced in a short period of time. Examples:TreesAgricultural crops (corn, wheat, rice, tomatoes, etc.)Clean drinking waterLiving thingsEnergy from the Sun

25.1 What are Resources?

It is possible to use renewable resources at a rate faster than they can be “renewed” Examples:Hunting species of animals into extinctionSpecies invasion into ecosystems caused by human

activity Sea lamprey introduced into the Great Lakes

Cutting trees down faster than they can regrow in a forest (deforestation) Haiti, upper Great Lakes region in the late 1800’s

25.1 What are Resources?

Non-Renewable resources are things on Earth that cannot be reproduced in a short period of time. Examples:Fossil fuels (Coal, Oil, Natural Gas)SoilDiamonds, Gold, Copper, Iron Ore

Non-renewable resources are replaced slowly by geologic chemical and physical properties that may take hundreds of millions of years to reproduce.

25.1 What are Resources?

Non-renewable resources therefore cannot be replaced in a human timeframe and are considered non-replaceable.

We must either find more of these resources if possible, or slow down the use of then to make them last.

Sustainable societies find a way to use energy and renewable resources at the same rate as the can be renewed.

Sustainable societies try conserve non-renewable energy or resources, or find alternatives where possible.

25.1 What are Resources?

Our economy and health depend on both renewable and non-renewable resources.

Our survival as a species also depends on these resources (especially clean water, air, and soil)

The human world population is growing and putting increasing pressure on both renewable and non-renewable resources.

World population growth

25.2 Land Resources

25.2 ObjectivesDescribe why land is considered to be a natural

resourceRecognize the need to protect Earth’s land as a

resourceDescribe the importance of productive land to

organisms on Earth

25.2 Land Resources

Arable soil is necessary for crop growth in addition to water, nutrients, and sunlight.

Topsoil takes thousands of years to form from the parent rock.

Each year Earth loses about seven percent of it’s topsoil, yet they must grow more food to support the increasing human population.

The land also supports natural vegetation which in turn supports wildlife.

25.3 Air resources

ObjectivesRecognize that the atmosphere is an Earth resource.Describe the importance of clean air to organisms on

Earth.

2.3 Air resources

Most of the life on Earth depends on the balanced exchange of gases in the atmosphere.

Human activities have altered this balance by releasing more carbon dioxide into the air while burning fossil fuels.

Pollutants released into the atmosphere air harmful to human health.

Air pollution can also come from natural sources ( volcanic eruptions and forest fires)

25.4 Water resources

ObjectivesExplain the importance of clean freshwater to

organisms on Earth.Explain the physical and chemical properties of

water.Explain how the properties of water support life on

Earth.Analyze how water is distributed and used on Earth. Identify ways in which humans can reduce the need

for increasing production of freshwater resources.

25.4 Water Resources

The Earth is often called “The Blue Planet” or “The Water planet” because 71 percent of the planet is covered with water.

Water is essential for life to exist. Biological actions take place with the aid of water.

Water is the “universal solvent”. Carries nutrients in, and waste products out of cells.

Water exists as a solid, liquid, or gas within the normal temperature ranges on Earth.

25.4 Water Resources

Water has a high specific heat. It takes a lot of energy to raise the temperature of water.

Water allows organisms that live in the water to survive because of temperature stability.

Water helps to stabilize the temperature of the planet.

25.4 Water Resources

Solid water is less dense than liquid water (only substance on Earth)

Allows organisms to live in colder temperature because the ice forms on top of bodies of water

Freezing water also helps to break up rock as it gets in the cracks and expands

25.4 Water Resources

Fresh water is not distributed evenly across the Earth.

Fresh water is held in surface waters or in the groundwater in aquifers.

In many dry areas water is pulled from these aquifers deep in the ground to irrigate crops. These aquifers are being depleted faster than they can be recharged.

Aquifers have been polluted in many areas by chemicals leaching into the ground from industrial activities.

Earth Systems - Hydrosphere

25.4 Water Resources

Water management

Dams & Reservoirs – these provide water, but have other environmental consequences (fish migration, beaches, etc)

Transporting fresh water (pipelines, aqueducts, etc.)

Groundwater (about 25% of water use in the U.S.)

Desalination – distillation of salt water to make fresh water.