Download Earth Science 4.3 Water, Air, Land Resources

Earth Science 4.3 Water, Air, Land
Resources
Water,
Air,
Land
Resources
Key Concepts

Why is fresh water a vital resource?

Why is the chemical composition of the
atmosphere important?

What are Earth’s important land
resources?
The Water Planet

Water covers nearly 71% of Earth’s surface

Most of this water is salt water, not fresh
water

While salt water oceans are important for
our climate and are an important part of our
ecosystem; fresh water is what we as
humans need to live.

Every day we use fresh water for drinking,
cooking, bathing and growing food

Less than 1% of the water on the planet is
usable fresh water
Freshwater Pollution

Contamination of our freshwater
supply is an important issue.

There are two types of water pollution
 Point Source Pollution
 Nonpoint Source Pollution
Point Source Pollution
 Point
source pollution is
pollution that comes from a
known and specific location
Nonpoint Source Pollution

Nonpoint source pollution does
not have a specific point of origin.

Runoff, the water that flows over
the land rather than seeping into
the ground, often carries nonpoint
source pollution

Runoff can carry waste oil from
streets, sediment from
construction sites, or pesticides
from farm soils

Water filtering through piles of
waste rock can carry sulfuric acid
into rivers and streams killing fish
Pollutants from eating
contaminated fish can
damage our bodies
major organs and
systems, cause birth
defects and cause
certain types of cancers
Earth’s Blanket of Air

Earth’s atmosphere is a blanket of
nitrogen, oxygen, water vapor and
other gases

The chemical composition of the
atmosphere helps maintain life on
Earth

First and foremost, people and
animals need oxygen to breath

The atmosphere is also part of
other cycles
Earth’s Blanket of Air

The carbon cycle of Earth’s
atmosphere makes vital nutrients
available to many life forms

The atmosphere also makes life
on land possible by shielding Earth
from harmful solar radiation
Earth’s Blanket of Air

Earth’s ozone layer high in the
atmosphere helps protect us from
solar radiation

Ozone is a three-atom form of
oxygen that protects Earth from
95% of the sun’s harmful
ultraviolet radiation

Certain greenhouse gases in the
atmosphere help maintain a warm
temperature near earth’s surface
Pollution in the Air

Pollution can change the
chemical composition of the
atmosphere and disrupt it’s
natural cycles and functions

Fossil-fuel combustion is the
major source of air pollution.
Most of this pollution comes
from motor vehicles and coal
or oil burning power plants
Pollution in the Air

Power plants release sulfur
dioxide and nitrogen oxide.
These pollutants combine
with water vapor to create
acid precipitation

The burning of fossil fuels
also produces carbon
dioxide, an important
greenhouse gas.
Pollution in the Air

The amount of carbon dioxide
in the atmosphere has
increased dramatically in the
past 100 years with the
industrial revolution

This increase has altered the
carbon cycle and contributed
to global warming. Global
warming could lead to huge
changes in the Earth’s
climate such as the melting of
polar ice caps.
Pollution in the Air

Chlorofluorocarbons (CFCs) destroy
ozone in the upper atmosphere. A
significant loss of ozone has resulted
in the increased risk of health
problems related to too much UV
radiation exposure such as skin
cancer and cataracts.

Because of a growing hole in the
Earth’s ozone layer, we now are
unable to spend time outdoors without
being conscious of the affects of sundamage to our skin
Pollution in the Air

Air pollution is a major public
health problem

Long term health effects
include asthma, bronchitis,
emphysema, and lung cancer

The US EPA estimates
200,000 deaths each year are
associated with the outdoor air
pollution
Land Resources

Earth’s land provides soil and forests,
as well as mineral and energy
resources

Removing and using resources from
earth’s crust can take a heavy
environmental toll.
Land Resources

There are essentially 500,000 mines
in the United States. While mines are
essential to our economy and energy
usage, mining tears up Earth’s
surface and often destroys the
landscape.

Mining also causes soil erosion,
creates pollution through runoff, and
contaminates surrounding water
supplies as well as destroys entire
ecosystems
Affects of Agriculture

Agriculture and farming have heavy
affects on the land as well

While many dry areas are now being
farmed thanks to irrigation, this heavy
pumping and water use is depleting
groundwater supplies in areas

Over time, irrigation causes
salinization ( the buildup of salts) .
Eventually the soil becomes useless
for plant growth. With the loss of plant
growth soil deteriorates and becomes
a dust bowl.