Download Modified Atmosphere in Vertical Activity

Activity:
The
Atmosphere
in
the
Vertical
Educational
Outcomes:
The
atmosphere
has
a
thickness
as
well
as
horizontal
extent.
For
a
more
complete
understanding
of
weather,
knowledge
of
atmospheric
conditions
in
the
vertical
is
necessary.
Air,
a
highly
compressible
fluid,
is
held
to
Earth
by
gravity
and
thins
rapidly
upward.
The
atmosphere
is
heated
primarily
from
below,
is
almost
always
in
motion,
and
contains
a
substance
(water)
that
undergoes
frequent
phase
changes.
The
atmosphere
is
also
affected
globally
by
greater
solar
heating
in
the
tropics
and
the
Earth’s
rotation
resulting
in
the
relatively
thicker
troposphere
of
the
tropical
regions
and
relatively
thinner
troposphere
in
polar‐regions.
After
completing
this
activity,
you
should
be
able
to:
Describe
the
vertical
structure
of
the
atmosphere
with
reference
to
temperature
changes,
air
pressure,
and
water
vapor.
Describe
the
vertical
structure
of
the
lowest
layers
of
the
atmosphere,
the
troposphere
(the
“weather”
layer)
and
in
the
lower
stratosphere.
Compare
the
“Standard
Atmosphere”
with
actual
soundings
from
the
lower
atmosphere
from
low
latitude
and
high
latitude
locations.
Compare
the
“Standard
Atmosphere”
with
actual
soundings
from
the
lower
atmosphere
from
a
station
close
to
your
geographical
“home”
location.
Describe
the
difference
in
thickness
of
the
troposphere
based
on
latitude.
Materials:
Copy
of
the
“Standard
Atmosphere”
Stüve
diagram,
straight
edge,
Color
Pencils,
Access
to
http://weather.uwyo.edu/upperair/sounding.html
for
“home”
sounding
data.
Investigations:
1.
Take
a
look
at
the
graph
you
were
provided.
This
type
of
logarithmic
graph
is
called
a
Stüve
diagram
and
it
is
designed
to
plot
and
interpret
upper‐air
atmospheric
data
that
has
been
acquired
by
radiosondes
as
they
rise
through
the
troposphere
and
into
the
lower
stratosphere.
The
ranges
of
atmospheric
temperature
in
Celsius
degrees
can
be
plotted
on
the
diagram
ranges
from
‐
________
to
+
________.
Air
pressure
is
plotted
in
millibars
(mb)
with
values
decreasing
upward
and
the
approximate
altitude
scale
is
in
kilometers
(km)
above
sea
level.
The
lowest
pressure
that
is
labeled
on
this
diagram
is
__________
mb.
This
pressure
is
found
in
the
atmosphere
at
an
altitude
of
about
_________
km
above
sea
level.
Figure
1:
Stüve
diagram
to
plotting
vertical
Atmospheric
temperature
and
pressure
change
Project
Atmosphere:
The
Atmosphere
Aloft,
Teacher’s
Guide,
(AMS,
1996)
2.
Using
one
of
your
color
pencils
plot
on
the
Stüve
diagram
the
data
points
given
below.
Connect
the
adjacent
points
with
solid
straight
lines.
Altitude
Temperature
(kilometers)
(degrees
C)
0
+15.0
11
‐56.5
16
‐56.5
3.
You
have
drawn
the
temperature
of
the
lower
portion
of
what
is
called
the
“Standard
Atmosphere.”
The
Standard
Atmosphere
describes
average
conditions
of
the
atmosphere
in
the
vertical.
The
portion
of
the
Standard
Atmosphere
from
the
surface
to
a
height
of
11
km
depicts
the
lowest
layer
of
the
atmosphere,
called
the
________________________
or
“weather
layer”
where
most
of
the
clouds
form
because
this
is
the
layer
where
almost
90%
of
atmospheric
water
vapor
is
found.
Above
11
km,
where
the
temperatures
remain
steady
or
begin
to
rise
with
altitude
is
the
lowest
portion
of
the
________________________
or
“stable
layer.”
The
boundary
between
these
two
layers
is
called
the
tropopause.
Through
the
entire
vertical
cross
section
of
the
atmosphere
there
are
“pauses”
where
the
temperature
stabilizes
and
then
reverses
previous
trend,
between
each
of
the
layers.
4.
The
actual
troposphere
is
characterized
generally
by
decreasing
temperature
with
altitude,
significant
vertical
motions,
appreciable
water
vapor,
and
weather.
(Fig.2)
Figure
2:
Variation
in
temperature,
pressure,
and
water
vapor
in
the
Atmosphere,
adapted
from
AMS
Weather
Studies
(Morin,
2012).
5.
6.
7.
8.
9.
According
to
the
data
provided
in
number
2
above,
the
rate
of
tropospheric
temperature
decrease
with
altitude
in
the
Standard
Atmosphere
is
____________
˚
C
per
km.
Air
pressure,
which
is
very
close
to
1000
mb
at
sea
level
in
the
Standard
Atmosphere,
decreases
most
rapidly
in
the
lowest
part
of
the
Standard
Atmosphere.
The
diagram
that
you
completed
of
the
Standard
Atmosphere
shows
that
near
sea
level
the
air
pressure
drops
100
mb
(from
1000
mb
to
900
mb)
over
a
vertical
distance
of
about
1
km.
However,
the
100‐mb
pressure
drop
from
400
mb
to
300
mb
occurs
over
a
vertical
distance
of
about
(1)
(2)
(3)
km.
The
same
pressure
drop
from
200
mb
to
100
mb
takes
place
over
a
vertical
distance
of
nearly
(1)
(2)
(4)
km.
Look
again
at
the
diagram
you
drew
of
the
Standard
Atmosphere.
At
about
what
altitude
does
the
500
mb
air
pressure
(half
of
that
at
sea
level)
occur?
__________
km.
Because
air
pressure
is
determined
by
the
weight
of
the
overlying
air,
half
of
the
atmosphere
by
weight
or
mass
is
above
the
altitude
where
the
air
pressure
is
500
mb
and
half
of
it
is
below
that
altitude.
In
other
words,
half
of
the
atmosphere
by
weight
or
mass
is
within
________
km
of
sea
level.
According
to
your
diagram
of
the
Standard
Atmosphere,
90%
of
the
atmosphere
by
weight
or
mass
is
within
_________
km
of
sea
level.
Upper‐air
observational
data
are
collected
twice
every
24
hours
at
nearly
100
stations
in
the
US.
The
following
data
were
measured
by
a
radiosonde
at
Lihue,
HI
(PHLI)
at
12Z
07
November
2012
(2
am
HST
on
7
November)
and
at
Barrow,
AK
(PABR)
at
12Z
07
November
2012
(3
am
AST
on
7
November).
Lihue,
HI
Barrow,
AK
Pressure
(mb)
Temperature
˚C
Pressure
(mb)
Temperature
˚C
100
‐75.3
100
‐54.9
200
‐53.3
200
‐55.9
300
‐35.3
300
‐58.1
400
‐20.5
400
‐45.1
500
‐6.9
500
‐33.7
600
2.8
600
‐24.0
700
6.0
700
‐17.1
850
13.4
850
‐13.9
1012
(surface)
24.2
1018
(surface)
‐3.7
Using
a
different
color
for
each
station,
plot
these
data
points
on
the
Stüve
diagram
that
already
has
your
Standard
Atmosphere.
Connect
adjacent
points
with
straight
lines.
Compare
the
Standard
Atmosphere
and
Lihue
temperature
profiles
you
drew
on
the
Stüve
diagram.
At
the
time
of
observation,
the
troposphere
over
Lihue
10.
11.
12.
was
generally
(warmer)
(colder)
than
specified
by
the
Standard
Atmosphere.
At
the
time
of
observation,
the
troposphere
over
Barrow
was
generally
(warmer)
(colder)
than
specified
by
the
Standard
Atmosphere.
According
to
the
plotted
temperature
profiles,
the
tropopause
(found
at
the
base
of
the
stratosphere)
where
temperatures
are
steady
or
increase
with
an
increase
in
was
located
at
_____________
mb
in
the
Standard
Atmosphere.
According
to
the
plotted
temperature
profiles,
the
tropopause
above
Lihue
is
located
at
__________
mb
and
the
tropopause
above
Barrow
is
located
at
__________
mb.
The
vertical
thickness
of
the
troposphere
at
Lihue
was
(greater)
(less)
than
the
thickness
of
the
Standard
Atmosphere.
The
vertical
thickness
of
the
troposphere
at
Barrow
was
(greater)
(less)
than
the
thickness
of
the
Standard
Atmosphere.
These
profiles
illustrate
the
general
relationship
between
average
tropospheric
temperature
and
the
vertical
extent
of
the
troposphere;
that
is,
the
(warmer)
(colder)
the
troposphere,
the
thinner
it
is.
This
relationship
means
that
on
the
average,
on
a
global
scale,
and
demonstrated
through
the
two
stations
that
you
plotted,
the
thickness
of
the
troposphere
(increases)
(decreases)
as
the
latitude
increases.
In
other
words,
on
average
the
troposphere
is
(thicker)
(thinner)
the
closer
your
geographical
location
is
to
the
equator
and
is
(thicker)
(thinner)
the
closer
your
geographical
location
is
to
the
pole.
(Activity
adapted
from
AMS
Project
Atmosphere
Activity:
The
Atmosphere
in
the
Vertical
(AMS,
1996).