Transcript Weather vs Climate , Thunderstorm notes

* Learning objectives
Why do geographers study the weather?
What is the difference between 'weather' and 'climate‘?
Climate graphs
Why does it rain?
* Why do geographers study the weather?
The weather has an impact on many of the things that we do!
Can you explain how the weather affects these people?
* Learning objectives
Why do geographers study the weather?
What is the difference between 'weather' and
'climate'?
Climate graphs
Why does it rain?
*
What is the difference between weather and climate?
Climate is the overall average pattern of weather and is usually measured on a
larger scale (continents, world)
Altitude
Oceans, Lakes,
Rivers
wind direction
Latitude
Precipitation
Topography
shape, height,
depth of land
Latitude
Heat is more
Concentrated
at the
Equator
The same heat
has further to
travel near the
poles of the
earth
Title the Map and color it according to the photo below
Elevation (altitude) Effects on Climate
Title the Map and color it according to the photo below
* Temperature and Rainfall effects Climate
Climate graphs are a way of showing how temperature
and precipitation vary throughout the year for a
particular place.
Climate chart for Queen Creek Arizona
* Plot your own climate
graph
Month
Jan
Rainfall
(in)
0.91
Temp
(0F)
56.5
Fe
Ma
Apr
Ma
Jun
Jul
Aug Sep
Oct
Nov Dec
Queen Creek, Arizona
Use this data to draw a climate graph for Queen Creek.
Graph should be titled (x axis, y axis, and main title)
Line Graph for Temp (in red)
Bar graph for Precipitation (in blue)
Number Y axis to 100 degrees F
Label the X axis the months of the year J F M A
* Plot a Climate Graph for Cape Town
Month
Rainfall
(in)
Temp
(0F)
Jan
Fe
Ma
Apr
Ma
Jun
Jul
Aug
Sep
Oct
Nov
Dec
0.82 0.86 1.25 2.83 4.7 5.7 5.11 4.9 2.76 2.16 1.18 0.98
68
69
67
60
55
52
49
45
48
53
58
60
Cape Town, South Africa
Use this data to draw a climate graph for Cape Town.
How does it compare to this climate graph of Queen Creek?
What makes it’s climate different?
*
* Clearly their day to day weather changes
* What OTHER factors did you learn about today that effects
Cape Town and Queen Creeks Climate?
* Learning objectives
Why do geographers study the weather?
What is the difference between 'weather' and 'climate‘?
Climate graphs
What is precipitation?
Why does it rain?
* What is precipitation?
Precipitation is water from the atmosphere.
It can be in solid or liquid form.
Name as many different types of precipitation as you can!
* Learning objectives
Why do geographers study the weather?
What is the difference between 'weather' and 'climate‘?
Climate graphs
What is precipitation?
Why does it rain?
There are three main types of rainfall – relief,
convectional and frontal.
* Why does it rain?
1. Warm moist air rises.
2. As air rises it cools and
condenses.
3. Condensed/cooled air forms
mini droplet that become to
heavy and falls.
* Convectional rain
* Convectional rain
* Relief
rain
* Relief rain
* Frontal
rain
* Key Ideas
Geographers study the weather because it has an impact on
people’s daily lives and the activities that they do.
Weather is the day to day changes in the atmosphere.
Climate is the overall average pattern of weather
Precipitation is water from the atmosphere.
It can be in solid or liquid form.
There are three main types of rainfall – relief, convectional and
frontal. In all three situations, rainfall occurs because air is
forced to rise.
*
Weather and Climate Unit
Investigative Science
*
* At any given moment, nearly 2000 thunderstorms are in progress
around the world.
* Most do little more than provide welcome relief on a muggy
summer afternoon, or provide a spectacle of lightning.
* Some, however, grow into atmospheric monsters capable of
producing hail the size of baseballs, swirling tornadoes, and
surface winds of more than 160 km/hour.
* These severe thunderstorms can also provide the energy for
nature’s most destructive storms—hurricanes!
*
* The stability of air is determined by whether or not an air mass
can lift.
* Cooling air masses are stable.
* Air masses that are warming from the air or land beneath them
are not stable.
* Under the right conditions, convection can cause a cumulus
cloud to grow into a cumulonimbus cloud.
* The conditions that produce a cumulonimbus cloud are the same
conditions that produce thunderstorms.
*
* For a thunderstorm to form, three conditions must exist:
* 1) a source of moisture
* 2) lifting of the air mass
* 3) an unstable atmosphere
*
* For a thunderstorm to form, there must be an abundant source of
moisture in the lower levels of the atmosphere.
* Air masses that form over tropical oceans or large lakes become more
humid from water evaporating.
* This humid air is less dense than the surrounding dry air and is lifted.
* The water vapor it contains condenses into the droplets that make up
clouds.
* Latent heat, which is released from the water vapor during
condensation, warms the air.
* This causes the air to rise further, cool further and condense more
water vapor.
*
* As moisture condenses into clouds, it releases its latent (stored)
heat.
* This occurs when a warm air mass is lifted into a cooler region
of the atmosphere.
* Dense, cold air along a cold front can push warmer air upward.
* Warm land areas, heat islands such as cities, and bodies of
water can also provide heat for lifting an air mass.
* Only when water vapor condenses can it release latent heat and
keep the cloud rising.
*
* If the surrounding air remains cooler than the rising air mass,
the unstable conditions can produce clouds that grow upward.
* This releases more latent heat and allows continued lifting.
* When the density of the rising air mass and the surrounding air
are nearly the same, the cloud stops growing.
* Cumulus clouds can become cumulonimbus clouds as the air
mass rises, cools, releases more heat, rises, cools again—over
and over.
*
*Air near surface is warmed during the day.
*Warm air rises and condenses to form
cumulous clouds in the afternoon.
*Scattered, isolated.
*Most moisture evaporates
but eventually it accumulates into
taller clouds.
*
*
36
*
Unstable air mass
37
Orographic lifting
over mountains
Forms when air converges, is forced up, cools
adiabatically, form clouds
These tend to be brief, shortlived storms with moderately
heavy downpours.
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3 Stages of Development of a Thunderstorm
Pg. 288
Stage 1
Cloud continues to
grow as long as there is
a supply of warm,
moist air.
Updraft occurs.
http://www.youtube.com/watc
h?v=DualOU_gBn0
41
Bergeron Process
Ice crystals
collect water
molecules and
grow larger
while cloud
droplets
evaporate and
get smaller.
*
* Mature stage
43
*
44
Developing
Cumulonimbus
FairWeather
Cumulus
Well-Developed Cumulonimbus
Severe Thunderstorm Development along a Cold Front
47
Roll
Cloud
http://www.youtube.com/watch?v=QHHUfb7olQ0
Average Number of Thunderstorm Days
Atmospheric
Hazard
Flash Floods - Number One Thunderstorm Killer
Supercell Thunderstorm
Supercell:
A single, very
large
(65,000 ft. high)
massive cloud
12-30- miles in
diameter,
Lasts for many
hours
Cluster of Supercell Thunderstorms
Temperature Inversion enhances formation of severe
thunderstorms: dense, cold layer above prevents warm, moist air
from rising.
Surface air heats up, and finally erupts upward, producing an
unusually large cumulus cloud
Mammatus
Sky
Microburst
Strong DOWNDRAFTS
Beneath the thunderstorm
Small 2.5 miles across
Cold dense, sinking air
Last 2-5 minutes
Also called wind shears
http://www.youtube.com/watch?v=fjFTH3s6BlM