NCEA Level 3 Earth and Space Science 91414 (3.5) – Page 1 of 6
SAMPLE ASSESSMENT SCHEDULE
Earth and Space Science 91414 (3.5): Demonstrate understanding of processes in the atmosphere system
Assessment Criteria
Achievement
Achievement with Merit
Achievement with Excellence
Demonstrate understanding involves explaining
processes and links within the atmosphere system.
Demonstrate in-depth understanding involves
explaining links between the processes in the
atmosphere system.
Demonstrate comprehensive understanding involves
discussing the complexity of the atmosphere system.
Evidence Statement
Q
Evidence
ONE
This is an example of a volcanically-induced climate
cooling event. Tambora erupted large quantities of
aerosols into the atmosphere. This aerosol layer led
to the drop in temperature worldwide.
The stratospheric sulfate aerosol layer which plays a
large role in modulating the net incoming radiation is
strongly influenced by volcanic sulfide released from
magma.
Climatic effects appear to result if the eruption is
powerful enough to inject material into the
stratosphere, or if the eruption is of sufficient
duration that a higher-than-normal level of
tropospheric aerosols is maintained.
Winds in the stratosphere spread the aerosols until
they practically cover the globe. Once formed, these
aerosols stay in the stratosphere for about two
years. They reflect sunlight, reducing the amount of
energy reaching the lower atmosphere and the
Earth's surface, cooling them.
Achievement
Explains the effect of matter /
aerosols in the atmosphere on
surface temperature over time.
Achievement with Merit
Achievement with Excellence
Explains in depth how the
aerosols from volcanic eruptions,
particularly sulfides, reduce the
temperature across the earth’s
surface over time.
Comprehensive discussion of
how aerosols from volcanic
eruptions, particularly sulfides,
affect radiation and result in the
decrease in surface temperature
of the earth.
NCEA Level 3 Earth and Space Science 91414 (3.5) – Page 2 of 6
http://www.nasa.gov/centers/langley/news/factsheets/Aerosols.html
NØ
N1
N2
A3
A4
M5
M6
E7
E8
No response,
no relevant
evidence.
The
atmosphere
affects sunlight
reaching the
earth.
Aerosols are in
the upper
atmosphere or
they reflect /
block the sun.
Explanation
given is
correct but
distance
(earth’s
surface) and /
or time is not
referred to.
Correct
explanation
including
reference to
distance
(Earth’s
surface) and
time.
In-depth
explanation,
but lacks
minor detail(s)
Nature (size or
length) of the
eruption(s) and
character
(sulphide)
referred to in
explanation.
Comprehensive
discussion but
lacks minor
detail(s).
Comprehensive
discussion
addresses the
atmospheric
characteristics
leading to
cooling of the
Earth’s surface
as in Evidence.
Note: Not
volcanoes
cause cooling
– this is in the
question.
Diagram not
essential, but
likely to be
present to
support
answer.
NCEA Level 3 Earth and Space Science 91414 (3.5) – Page 3 of 6
TWO
The Hadley cell is a closed convection loop that
begins to rise (creating a low pressure area) at the
equator due to the air being warm and moist. It
moves outward towards the poles. At approx. 30° N
or S latitude it descends, creating a high pressure
area. Some of the descending air travels along the
surface creating the trade winds.
The Polar cell is similar to the Hadley cell but occurs
at the 60th parallel. The warm air rises at this latitude
and moves towards the poles. When the air reaches
the polar areas it has cooled and descends as cold
high pressure areas. The air then moves away from
the poles along the surface to produce the Polar
easterlies.
Both the Polar and Hadley cells are a result of
surface temperatures. They are also very stable and
are not affected by passing weather systems.
The Ferrel cell is a secondary convection feature
that is dependent on the Hadley and Polar cells for
its existence. The Ferrel cell is a result of interaction
between the high and low pressure areas at the midlatitudes. It results in the (prevailing) Westerlies.
The Ferrel cell is not a true closed convection loop
like the Hadley or Polar cell and can be affected by
passing weather systems.
http://www.geology.wmich.edu/kominz/images1/ATM_Convection
%20MAK.jpg
Explanation of three convection
cells and an outline of the
processes they involve.
Explanation of how the three
convection cells work and how
they are related to each other
Comparison of the three
convection cells, their interaction
and the effects on the
atmosphere explained in depth.
NCEA Level 3 Earth and Space Science 91414 (3.5) – Page 4 of 6
NØ
N1
N2
A3
A4
M5
M6
E7
E8
No response,
no relevant
evidence.
The idea of
convection
correctly
described.
ONE cell briefly
explained
TWO of
THREE cells
briefly
explained
All THREE cells
briefly
explained.
TWO cells
explained in
terms of
convection
and their
link(s)
explained.
All THREE
cells explained
in terms of
convection and
their link(s)
explained.
Interaction(s)
of THREE cells
explained in
depth. One cell
may be less
clearly
explained or an
interaction may
be less clear.
Interaction(s)
of all THREE
cells explained
in depth.
NCEA Level 3 Earth and Space Science 91414 (3.5) – Page 5 of 6
THREE
Sunlight (heat energy) passes through the
atmosphere to the surface of the Earth. Normally
much of this heat energy is radiated back towards
space. However, in the case of global warming, the
outgoing heat is absorbed by certain gases in the
atmosphere. This blocks some heat from escaping
the atmosphere, thus resulting in an increase in
global temperature.
Gases that contribute to the greenhouse effect
include:




Water vapour. The most abundant greenhouse
gas, but importantly, it acts as a feedback to the
climate. Water vapour increases as the Earth's
atmosphere warms, but so does the possibility
of clouds and precipitation, making these some
of the most important feedback mechanisms to
the greenhouse effect.
Carbon dioxide (CO2). A minor but very
important component of the atmosphere, carbon
dioxide is released through natural processes
such as respiration and volcano eruptions, and
through human activities such as deforestation,
land use changes, and burning fossil fuels.
Humans have increased atmospheric CO2
concentration by a third since the Industrial
Revolution began. This is the most important
long-lived ‘forcing’ of climate change.
Methane. A hydrocarbon gas produced both
through natural sources and human activities,
including the decomposition of wastes in
landfills, agriculture, and especially rice
cultivation, and ruminant digestion and manure
management associated with domestic
livestock. On a molecule-for-molecule basis,
methane is a far more active greenhouse gas
than carbon dioxide, but also one that is much
less abundant in the atmosphere.
Nitrous oxide. A powerful greenhouse gas
produced by soil cultivation practices, especially
the use of commercial and organic fertilizers,
Explains what happens when
sunlight (heat energy) arrives at
the atmosphere, and how this
changes when greenhouse
gases are present in the
atmosphere because of the
insulating effect.
Explains causes of global
warming including explanation of
origins and impact of
greenhouse gases.
Discusses causes of global
warming, including explanation
of origins and impact of
greenhouse gases.
Evidence for the overall effect on
the earth over time is explained.
NCEA Level 3 Earth and Space Science 91414 (3.5) – Page 6 of 6

fossil fuel combustion, nitric acid production, and
biomass burning.
Chlorofluorocarbons (CFCs). Synthetic
compounds of entirely industrial origin used in a
number of applications. Now largely restricted in
production and release to the atmosphere, by
international agreement, because of their ability
to contribute to destruction of the ozone layer.
They are also greenhouse gases.
As the amount of these gases increases in the
atmosphere the amount of heat energy that gets
trapped increases. This is what leads to the increase
in global temperature.
NØ
N1
N2
A3
A4
M5
M6
E7
E8
No response,
no relevant
evidence.
Role of
atmosphere in
temperature
control given.
General idea of
global warming
given.
Answer at
Achievement
level but
some details
unclear.
Full answer at
Achievement
level.
Answer at
Merit level but
detail about
only ONE or
TWO gases
given.
Full answer at
Merit level
referring to
MORE THAN
TWO of the
gases named in
question.
Full discussion
of global
warming with
some
supporting
details
showing
comprehensive
understanding.
Full discussion
of global
warming with
supporting
details showing
comprehensive
understanding.
Note: gases
contributing to
greenhouse
effect are given
in the question.