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!