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/
Office Hours
Climate ClassificationClimate ClassificationLesson 19Lesson 19
ClimographsKöppen Classification System & ProceduresClimate 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: ModifiedFirst-Order Divisions
Temperature-based A: Tropical B: Dry C: Mesothermal D: Microthermal E: Polar H: Highland
Köppen System:Second-Order Divisions
Precipitation based f: year-round rainfall m: monsoon rainfall s: summer dry season w: winter dry season
Köppen System:Third-Order Divisions
Based on summer temperatures 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: ModifiedMajor Climate Types
Köppen System: Major World Climates
Climate Controls
Factors that govern local weather and climate Five major controls of climate
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
Postponed!