Download World Biomes and Climatographs - classroom ppt

World Biomes and Climatographs
History:
•
Ancient Greeks used to classify the
environment into zones which had
different degrees of warmth. This
resulted in Aristotle describing the
terrain in terms of flora and fauna.
•
Main characteristics and variables used
to define biomes is:
Precipitation
Temperature
1.
2.


•
Climate - 30 year records.
Invention of instruments in the 17th and
18th century allowed for data and
records to be used for classification of
global climates
The main elements of the weather that
are measured are1. Temperature
2. Wind (Direction and Speed)
3. Humidity
4. Precipitation
5. Sunshine
World Biomes Map
•
Our world is a diverse and beautiful place filled with a range of environments.
•
As Earth scientists, we strive to understand the Earth as a system and how each
part compares and works with another. This functionality defines the study of
both the atmosphere and Earth’s surface.
•
We know that heat transfer occurs constantly due to uneven heating of the Earth’s
surface and this effects the physical and biological landforms based on the climate
conditions, controlled by convective cells and solar insolation.
World Biomes and Climatographs
Earth’s tropospheric convective cells are the driving
force behind the surface landforms , weathering and
erosion and the physical and biological processes
that occur in each particular region of the planet.
Air pressure systems/belts control the function and
resultant environmental processes based on the
simple rule of whether air rises or sinks.
Evaporation, condensation, precipitation and air
instability are all created by rising air in areas of
low pressure.
The creation of systematic and symmetrical areas of
low and high pressure produce similar surface
environments consistent with precipitation and the
amount of sunlight annually (temperature) .
1) Latitude and its influence on solar
radiation received.
2) Air mass influences.
3) Location of global high and low pressure zones.
4) Heat exchange from ocean currents.
5) Distribution of mountain barriers.
6) Pattern of prevailing winds.
7) Distribution of land and sea.
8) Altitude.
Atmospheric Circulation and
Biomes
In general:
0 Degrees (ITCZ/Doldrums/Equatorial)
- Tropical Rainforest
20-35 Degrees (Horse lats )
- Arid/Hot/Dry deserts
30-50 Degrees (Ferrel cell – midlatitudes)
- Subtropical regions, Chapparal,
Savannah, grasslands)
40-60 Degrees (Mid-latitides – subpolar low)
- Moist continental climates, cold
winters, warm summers
Polar regions – warmest month below
10^C (average)
Atmospheric Circulation and
Biomes
Köppen Classification System:
Wladimir Koppen a German botanist
and climatologist studied and divided
the Earth into climate regions using
temp and precip statistics.
5 main divisions based on annual
temperatures:
A - Tropical Moist Climates: all
months have average temperatures
above 18° Celsius.
B - Dry Climates: with deficient
precipitation during most of the year.
C - Moist Mid-latitude Climates with
Mild Winters.
D - Moist Mid-Latitude Climates with
Cold Winters.
E - Polar Climates: with extremely
cold winters and summers.
Temperature vs. Precipitation
We start at the Equator…….
• As per the convective cell circulation model, our climate system and classification begins
at the equator.
• Each hemisphere is generally symmetrical with minor differences based on altitude,
terrain, distance from water, availability of sunlight, leeward/windward, jet stream
location.
Tropical Rainforest
•
•
•
•
•
•
•
•
•
•
•
Precipitation: 250cm rainfall per
year
Average temp = 77F (25’C)
Daytime = 30-35C,
Night time = 20-25C
Daylight length – 12 hours
Relative Humidity = 75%
Why does this area have a large
precipitation
Link this to the latitude
Link this to the elevation or
topography
Link this to the prevailing winds,
wind speed and proximity to oceans
(humidity)
Length of day and exposure to Sun’s
radiation
Desert (hot)
-
-
-
-
Precipitation must be below 50 cm per
year to qualify
Many mean annual temperatures range
from 20-25° C. The extreme maximum
ranges from 43.5-49° C. Minimum
temperatures sometimes drop to -18° C.
Limited precipitation therefore limits
the vegetation and domestic animal
species
Harsh environment causes specific
adaptations to occur in order to be
successful in this climate, terrain and
conditions.
Link this biome to:
-
Why precipitation is low
Why the prevailing winds are warm
Climatic conditions causing a change
from soil to sand
The extent of such desert biome over a
certain latitude
Chaparral/Grassland/Savanna
These biomes are very similar in their temperature and precipitation
(average per year):
Chaparral:
• Mediterranean Climate (warm)
• Hot and dry summers
• Located between 30-50
Savannah:
• Tropical climate
• Winter dry season
Grassland:
- Cold winters, long dry season
- Interior of continents
- 25% of world is covered by grasslands in different forms
Chaparral
Grassland
Savannah
Precipitation
25-43 cm 81cm
100-150cm
Temperature
15C
16-20C
31C
Chaparral/Grassland/Savanna
Deciduous Forest
• Average temperature
(annual) - 10’C
• 75-150 cm of precipitation
annual
• Changes with the seasons
• Tilt influences this climate
through fluctuating solar
insolation and sun’s angle in
the sky
• Has definitive growing
seasons
• Is interacting with midlatitude weather systems
Boreal Forest/Taiga
- Average range of
temperate -5’C to 5’C.
- Particular latitudes dictate
the amount and timing of
precipitation.
- Range of 20cm to 200cm
- Controls certain
vegetation and animal
species
- Growing season is short
- Longer winters and
sustained permafrost
Polar Desert (cold)
Difference between Arctic and Antarctic Polar
Regions:
Land comparison (size of region):
Arctic – 5.8 million square miles (fluctuates
between summer and winter)
Antarctic – 5.4 million square miles (land
mass) + 6.9 – 1.1 million square miles of sea
ice (fluctuates)
Climate Differences:
Winter season:
Arctic –
Antarctic –
Ice thickness:
Arctic – 6ft (thinner – less dense)
Antarctic – 3ft (thicker – dense)
Temperatures (range):
- South Pole -60C to -28C
- North Pole -40C to 0C