Download Climate - MSU Billings

Climate
Global Climates
What is Climate?
How are Climates Classified?
Climates by Latitude
Low
Middle
High
Climate in the Mountains
Changing Climate
What is Climate
Climate – the average weather (temperature
and precipitation) of a region >> climatology
Temperature Regime – based on latitude,
location, elevation >> total range and
seasonality
Precipitation –patterns controlled by air masses
and their movements (influenced by
atmospheric circulation patterns) >> total
precip and seasonality
Temperature Patterns
Winter
Temperature Patterns
Summer
first
later
Temperature Regimes by Latitude
WET
DRY
WARM
COLD
Temperature Regimes
Ocean Surface Currents
Midlatitude “gyres” contribute to zonal asymmetry in subtropics:
cold on west coasts, warm on east coasts
Monsoon
Monsoon
15
Polar
Tundra
Boreal Forest
Temperate Forest
Desert
Grassland to savannah
Equatorial to Tropical
Grassland to savannah
Desert
Temperate Forest
Boreal Forest
Tundra
Polar
Equator
IG4e_07_02a
IG4e_07_02b
Precipitation Regimes
High convectional precipitation at equatorial
regions
Subtropical highs pressure cells (dry, subsiding
air)
Mountain ranges produce wet areas
Coastal mountains can act as barriers to
produce rain shadows
Continental interiors tend to be dry
Precipitation patterns:
Uniformly distributed precipitation seasonally
Precipitation maximum during the warmest
period of the year (high sun season)
Precipitation maximum during the coolest
period of the year (low sun season)
Seven global precipitation regions:
Wet equatorial
Trade wind coasts
Tropical Deserts
Midlatitude deserts and steppes
Moist subtropical
Midlatitude west coasts
Arctic and Polar Deserts
Precipitation Regimes
Precipitation Regimes
Climate Classification
Based on the scheme first developed by Dr.
Vladimir Köppen in 1918
Low Latitude Climates
Mid-latitude Climates
High Latitude Climates
Climate Classification (Köppen)
Köppen Climate Classification (Type A: Tropical Climates)
Figure S7.3, p. 224
Köppen Climate Classification (Type B: Dry Climates)
Global Climates (Köppen)
Figure S7.2, p. 224
Global Climates (Köppen)
Things to Consider:
Low-latitude locations have warmer
temperatures and smaller annual temperature
ranges than high-latitude locations
Continental locations tend to have much larger
annual temperature ranges than coastal
locations at the same latitude
Colder locations tend to have less precipitation
than warm locations because warm air can hold
more moisture than cold air
Low
Latitude
Climates
Low Latitude Climates
occupy equatorial, and much tropical and
subtropical zones
range from very wet to very dry
influenced by the intertropical convergence
zone (ITCZ), tropical easterly systems and
subtropical high-pressure cells
experience traveling lows such as the easterly
wave and tropical cyclones
Low Latitude Climates
Low Latitude Climates: wet equatorial
The Amazon
dominantly influenced by the intertropical
convergence zone (ITCZ)
mE and mT air masses
uniform, very warm temperatures in all seasons
ample precipitation, heaviest in direct
association with the ITCZ
IG4e_07_12
Low Latitude Climates: wet equatorial
Figure 7.9, p. 233
IG4e_07_08
IG4e_07_08b
Low Latitude Climates: Monsoon and
trade wind coastal climates
India, Central America, SE Asia
heavy rainfall with strong seasonal patterns
larger temperature range than wet equatorial climate
dominance of the ITCZ during the heavy rainfall period
and the subtropical high pressure system during the dry
season
trade wind coast climates are a result of mT and mE air
masses
Low Latitude Climates: trade wind
coastal climates
Figure 7.10, p. 233
IG4e_07_14
IG4e_07_11
IG4e_07_opener
Low Latitude Climates: wet-dry tropical climates
a warm climate with a more marked temperature range
during high sun season, proximity to ITCZ brings heavy
rains
during low sun season, subtropical high produces very
dry conditions
vegetation is rain-green (dormant during dry season,
productive during wet season)
IG4e_07_14b
Low Latitude Climates: wet-dry tropical climates
Figure 7.14, p. 236
IG4e_07_p238
IG4e_07_15
IG4e_07_p239
IG4e_07_p239b
Low Latitude Climates: dry tropical climates
Low latitude Deserts
dominated by subtropical high-pressure cell
very low precipitation and intense daytime heating
under predominantly clear skies
includes many of the world's great deserts
semi-arid areas on the edges of the desert may have a
short wet season
Low Latitude Climates: dry tropical climates
Figure 7.17, p. 241
IG4e_07_16a
IG4e_07_16b
IG4e_07_22
IG4e_07_18a
IG4e_07_18b
IG4e_07_18c
IG4e_07_18d
IG4e_07_18e
Mid
Latitude
Climates
Midlatitude Climates
occupy all of midlatitude zone and part of subtropics
zone
zone of interaction between tropical and polar air
masses
marked by traveling cyclones, anticyclones and frontal
boundaries
strong annual variations in temperature and
precipitation
IG4e_07_20
Midlatitude Climates: dry subtropical climate
southwest USA
poleward extension of dry tropical climate, but with
greater annual temperature range (higher latitude)
cool season (air from higher latitudes) and occasional
precipitation from midlatitude cyclones
divided into arid and semi-arid subtypes
more vegetation than dry tropical (lower temperatures
and more precipitation)
Midlatitude Climates: dry subtropical climate
Arizona
Figure 7.21, p. 246
Midlatitude Climate: moist subtropical climate
New Orleans, Florida, SE Asia
warm, moist air flowing out of the subtropical high and
influencing the eastern sides of continents
abundant summer rainfall, mainly convectional with an
occasional tropical cyclone
Southeast Asia experiences strong monsoon
winter precipitation from wave cyclones
Midlatitude Climate: moist subtropical climate
Figure 7.24, p. 248
IG4e_07_23a
IG4e_07_23b
IG4e_07_25
Midlatitude Climates: Mediterranean climate
California, Italy, Greece
very dry summer due to migration of the subtropical
high-pressure cell into the area
low sun season is dominated by rainfall provided by cP
air masses and cyclonic storms
has a moderate temperature range
limited to narrow coastal zones
Midlatitude Climates: Mediterranean climate
Figure 7.26, p. 249
IG4e_07_27a
IG4e_07_27b
IG4e_07_28b
IG4e_07_28c
IG4e_07_28d
Midlatitude Climates: marine west coast climate
Northern California to British Columbia, Ireland
mild temperatures with a small temperature range
moist climate with a low sun season precipitation
maximum due to frequent cyclonic storms
during the high sun season the northward movement of
the subtropical high pressure cell reduces precipitation
Midlatitude Climates: marine west coast climate
Norway, Washington, British Columbia
Figure 7.29, p. 254
IG4e_07_30
IG4e_07_31
Midlatitude Climates: dry midlatitude climate
e.g. Montana
interior regions of North America and Eurasia
high sun season rainfall is convectional and associated
with occasional maritime air masses
strong annual temperature range with hot high sun
seasons and cold low sun seasons
includes arid cold desert and semi-arid steppes
Midlatitude Climates: dry midlatitude climate
Wyoming, Montana, Pampas
Figure 7.32, p. 255
Midlatitude Climates: moist continental climate
central and eastern North America and Eurasia
large seasonal temperature variation and strong day-today variation
ample precipitation peaking in the high summer season
with mT air masses
Low sun season is dominated by cP and cA air masses
Midlatitude Climates: moist continental climate
Midwest USA, Toronto
Figure 7.33, p. 256
IG4e_07_34a
IG4e_07_34b
IG4e_07_35
High
Latitude
Climates
High Latitude Climates
located in the westerly wind belt
influenced by mP air masses conflicting with cP
and cA air masses and wave cyclones which
develop along the arctic-front zone
experience greater high sun season
precipitation brought in by mT air masses
IG4e_07_36
High Latitude Climates: boreal forest climate
long, bitterly cold low sun seasons and short cool high
sun seasons
very large annual temperature range (continental
location)
source region for cP air masses and invasions of cA air
masses are common
low total annual precipitation with a high sun season
precipitation maximum
High Latitude Climates: boreal forest climate
Figure 7.38, p. 260
IG4e_07_39
IG4e_07_37a
IG4e_07_37b
High Latitude Climates: tundra climate
is found along arctic coastal areas
long severe low sun seasons dominated by cP, mP, and
cA air masses
smaller temperature range for its latitude (moderating
effect of ocean)
vegetation consists of grasses, sedges, lichens and
some shrubs
cold enough to create permafrost
IG4e_07_42
High Latitude Climates: tundra climate
Figure 7.41, p. 261
High Latitude Climates: ice sheet climate
source region of Arctic and Antarctic air masses
ice sheets of Greenland and Antarctica and
over the Arctic ocean ice
lowest mean annual temperature, no month has
a mean temperature above freezing
very low precipitation
High Latitude Climates:
ice sheet climate
Figure 7.43, p. 263
IG4e_07_40
Highland (Mountain) Climates
cool to cold, usually moist climates that occupy
mountains and high plateaus