Earth’s Energy Balance (slide 3) Flashcards
Radiation
is when energy travels as waves
Ex- Ultraviolet (U.V.) radiation from the sun
Conduction
is when energy is transferred through contact
Ex- The handle of a metal pan getting hot when it is heated
Convection
is when energy is transferred because of
differences in temperatures in a liquid or gas
Ex- ocean currents, or warm air rising and cool air falling
Earth maintains a relatively constant global temperature-
a unique quality that
allows it to be able to maintain life
Planets such as Mercury can be heated up 450 degrees Celsius from the Sun
Why doesn’t Earth get scorching hot?
earth has an atmosphere and it is further away from the sun
incoming solar energy
100%
reflected by atmosphere
6%
refleceted by clouds
20%
reflected by earth’s surface
4%
absorbed by atmosphere and clouds
19%
absorbed by land and oceon
51%
reflected back into space
30%
energy is absorbed onto Earth
70%
If there is an energy balance then that would mean:
the amount of energy absorbed = the amount of energy released
The absorbed 70% of
energy is actually
converted
to heat
The oceans and land begin
to radiate that heat
back
out into the atmosphere
and eventually back to
space
Energy absorbed by living
things will also radiate
thermal energy
back into
space
Other planets like Mercury do not have an atmosphere therefore it is unable to
reflect light (450 degrees C)
during the day and retain heat during the night (-170 degrees C)
It is important for the energy to be converted to thermal energy because
it allows Earth to stay warm
It is important for the energy to be immediately reflected back into space and have the thermal energy
slowly radiate back into space so
Earth does not reach scorching hot temperatures
Earth’s ability to sustain life is because its
climate system
Earth’s climate system is composed of the
atmosphere, hydrosphere, lithosphere,
and living things (sometimes biosphere)
Atmosphere
The atmosphere is made of layers of gases surrounding Earth
Hydrosphere
The hydroshere includes liquide water in lakes and oceons, water vapour in the atmosphere and ice in glaciers and at the poles.
Lithosphere
The lithosphere is Earth’s rock crust including land surfaces
living things
all living things on Earth are part of the climate.
There are many gases that make up the atmosphere; the major ones that we
breathe are:
nitrogen (78%), oxygen (21%), combination of argon and carbon
dioxide (1%), and traces of helium, hydrogen, ozone, and water vapour
The atmosphere is important because it reflect energy from the Sun to keep the
earth cool during the
day and keep the dangerous radiation away from living
things
It also absorbs and radiates thermal energy (traps heat on Earth)
to keep the
planet warm during the night
Ozone is a
naturally occurring gas in our atmosphere
Ozone in the stratosphere is responsible for
absorbing/reflecting harmful
UV radiation and reflecting it away from Earth.
Issue:
CFC’s are manufactured very stable compounds used in
pressurized sprays and
refrigerators
When CFC’s are released into the atmosphere they deplete the ozone in the stratosphere,
which allows more UV radiation to reach living organisms
The hydrosphere is composed of
all water, water vapour, and ice on Earth
The hydrosphere plays a major role in Earth’s climate system
(over 70% of Earth is
comprised of water)
Liquid water and ice reflects
energy
Liquid water and water vapour absorb energy
and radiate it as thermal energy (keeps
Earth warm
Hydrosphere and Ice Sheets
Global warming caused by accumulating levels of greenhouse gases are
melting ice
throughout the world
Increased levels of melting ice will cause
rising sea levels and a variety of other issues.
The lithosphere is composed of
the earth’s crust
The lithosphere reflects
some energy
The lithosphere absorbs energy and
radiates it as thermal energy
Lithosphere and Rising Sea Levels
Issue:
The amount of liveable space is dictated by the amount of water around us
(we are unable
to live on water)
If we do not have enough land to sustain our population we will be unable
to maintain the
current population
As sea levels rise, coastal communities will be
flooded
Biosphere- Living Things
Living things are composed of the organisms
that live on Earth
Living organisms generally absorb energy from the Sun
and radiate thermal (heat)
energy
Plants can absorb CO2 and release
O2 into the atmosphere (removing GHG 🡪 cools
Earth)
Animals release CO2 and CH4 into the atmosphere
(adds GHG 🡪 warms Earth)
Greenhouse gases (GHG) accumulate in the atmosphere to warm Earth
Issue:
More agriculture and farms and a higher population of living animals can lead to
more GHG’s and global warming
More clear-cutting of trees leads to less removal of
GHG’s and global warming
