Transcript GEOG101L_Lesson_19

Office Hours
Wed: 11:30 AM to 12:30 PM
Thr: 9:15 AM to 12:30 PM
Fri: 10:00 AM to 12:00 PM
Course Syllabus can be found at:
http://www.wx4sno.com/portfolio/BSU/spring_2012/
This lecture will be posted AFTER class at:
http://www.wx4sno.com/portfolio/BSU/spring_2012/lectures/
Climate Classification
Lesson 19
Climographs
Köppen Classification System & Procedures
Climate Controls
Climographs
 Climographs, or climatic diagrams, provide
an overview of climate at a certain location
 Can span hours, days, months, but usually are a
one year average
 Months are listed along the bottom
 Monthly temperature is shown as a solid line
 Temperature scale along the left side
 Monthly precipitation shown as bars
 Precipitation scale along the right side
Indianapolis, IN, USA (Dfa)
Minsk, Belarus (Dfb)
Yukon Territory, Canada (Dfc)
Climate Classification Purpose
 Simplify the complexities that comprise the climate
system
 Summarize climate information
 Schemes minimize the within group variability and
maximize the between group variability
 All locations within a group are very similar to one another,
but different from other groups
 Long-term shifts in climate boundaries
 Climate variability
 Biophysical impacts
Climate Classification Usefulness
 Examine the expected weather patterns for
climate based forecasting
 What’s the upcoming winter going to be like?
Lots of rain or lots of snow?
 Long-term shifts in climate boundaries
 Can we expect the “humid South” to shift north,
changing Indiana’s climate over the next
century?
Quantitative Classification:
Köppen System
 Developed first world
“climate classification” in
the 1870s
 Hierarchical scheme
 15 types (e.g. Dfa)
 Based on monthly data:
 Temperature
 Precipitation
 Corresponds with biomes
Wladimer Köppen
(1846-1940)
Köppen System: Modified
 Numerous modifications since inception
 Most widely used—fairly simplistic
 Defined the ecotone (or biome boundaries)
Grassland-forest ecotone: Paraguay
Köppen System: Modified
First-Order Divisions
 Temperature-based
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A:
B:
C:
D:
E:
H:
Tropical
Dry
Mesothermal
Microthermal
Polar
Highland
Köppen System:
Second-Order Divisions
 Precipitation based
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f: year-round rainfall
m: monsoon rainfall
s: summer dry season
w: winter dry season
Köppen System:
Third-Order Divisions
 Based on summer temperatures
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a: hot summers
b: warm summers
c: cool/mild summer
Arid climate
 h: hot and dry
 k: cold and dry
 Special: fog occurrence (n / n’)
Using the Flow Chart
Using the Flow Chart
Tropical Climates (A)
Climate: Af
Mesothermal or Mild Climates
(C)
Climate: Cfa
Microthermal or Severe
Midlatitude (D)
Climate: Dfb
Polar Climates (E)
Climate: ET
Köppen System: Modified
Major Climate Types
Köppen System: Major World Climates
Climate Controls
 Factors that govern local weather and climate
 Five major controls of climate
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Latitude and season
Water proximity (continentality)
Oceanic circulation
Semi-permanent pressure systems
Topography
Latitude: Insolation Variability
 Variation in solar angle striking surface
 Attenuation: depletion of solar rays
Latitude: Insolation Variability
 Atmospheric path length varies due to the
curvature
of the earth
Earth-Sun Relationships
 Rotation: spin of earth about its axis
 Approximately 15 degrees longitude/hr
 Daylight length
Water Proximity: Continentality
 Influence of large land mass
 Variable energy fluxes dependent on surface type and
their respective specific heat capacities
Oceanic Circulation: Surface
Oceanic Circulation: Deep Water
Semi-permanent Pressure Systems
NH: Surface/Upper Level Flow
Topography
 Normal lapse rate: 6.5° C/km
 Large diurnal temperature ranges at higher
elevations. Why?
 Varying insolation absorption rates
 Orographic effects
Homework
 For the climographs, please use English
units
 °F
 in
Extra Credit #2