Global Climate SystemsGlobal Climate SystemsGlobal Climate SystemsGlobal Climate Systems

GPH 111GPH 111

Local Climate Conditions: Local Climate Conditions: Local Climate Conditions: Local Climate Conditions:

Monsoon (summer rain)Monsoon (summer rain) Frontal (winter rain)Frontal (winter rain)

Monsoon (summer rain)Monsoon (summer rain) Frontal (winter rain)Frontal (winter rain)

Monsoon means a “change in the winds”

Winds shift from “West” to “East” Azores High Pressure moves

westward, driving winds off the Gulf of Mexico and California into Arizona.

Monsoon means a “change in the winds”

Winds shift from “West” to “East” Azores High Pressure moves

westward, driving winds off the Gulf of Mexico and California into Arizona.

1. Summer Monsoons1. Summer Monsoons

1. Azores High Pressure1. Azores High Pressure

1. High Dew Points1. High Dew Points Arizona’s monsoon starts when three

days in a row have dew points 55 degrees or higher.

Moisture comes from the Gulf of Mexico and Gulf of California.

Lifting Mechanisms: Convection, Orographic, Downdraft

Need to lift the air to cool it and generate rain

Arizona’s monsoon starts when three days in a row have dew points 55 degrees or higher.

Moisture comes from the Gulf of Mexico and Gulf of California.

Lifting Mechanisms: Convection, Orographic, Downdraft

Need to lift the air to cool it and generate rain

1. Lifting Mechanisms: Convection

1. Lifting Mechanisms: Convection

1. Lifting Mechanisms: Orographic

1. Lifting Mechanisms: Orographic

1. Lifting Mechanisms: Orographic

1. Lifting Mechanisms: Orographic

1. Lifting Mechanisms: Downdraft

1. Lifting Mechanisms: Downdraft

2. Winter Frontal Systems2. Winter Frontal Systems

Dominant air masses: Warm Moist to the south Cold and Dry to the north

Low pressures from the jet stream spin counter-clockwise

This forces the warm moist air over cold dry air, causing storms

Dominant air masses: Warm Moist to the south Cold and Dry to the north

Low pressures from the jet stream spin counter-clockwise

This forces the warm moist air over cold dry air, causing storms

2. Winter Frontal Systems2. Winter Frontal Systems

2. Winter Frontal Systems2. Winter Frontal Systems

2. Winter Frontal Systems2. Winter Frontal Systems

3. Phoenix Climate graph3. Phoenix Climate graph

Major Climate Major Climate Components: Components: Major Climate Major Climate Components: Components:

InsolationInsolation TemperatureTemperature Air PressureAir Pressure Wind BeltsWind Belts Air MassesAir Masses PrecipitationPrecipitation

InsolationInsolation TemperatureTemperature Air PressureAir Pressure Wind BeltsWind Belts Air MassesAir Masses PrecipitationPrecipitation

What controls TemperatureWhat controls TemperatureWhat controls TemperatureWhat controls Temperature

1) Latitude* – Lower latitude warmer and more moderate, higher latitude cooler and more extreme

2) Continentality* – Close to ocean more moderate, far from ocean more extreme

The importance of Latitude…The importance of Latitude…

And Continentality…And Continentality…

Where coastal regions experience moderate temperatures compared to locations inland because it is much harder to change the temperature of water compared to land.

Where would you rather vacation, Wichita or San Diego?

Reasons for…Reasons for…Dry seasonsDry seasons1) High pressure systems*High pressure systems*

2) Bounded by cool ocean currents**

Reasons for…Reasons for…Wet seasons (Review)Wet seasons (Review)1) Convergent*Convergent* – ITCZ

2) Convection* Convection* – Heating

3) Frontal*Frontal* – Cold Fronts

Wet versus Dry…Wet versus Dry…Wet versus Dry…Wet versus Dry…

Desert Causal Elements:1) High Pressure Systems

Desert Causal Elements:1) High Pressure Systems Great Victoria Desert, AU

Desert Causal Elements:2) Bounded by cool ocean currents

Desert Causal Elements:2) Bounded by cool ocean currents

Atacama Desert, Chile

Tropical [A] (tropical latitudes mild year round)Tropical [A] (tropical latitudes mild year round)- rain forest (rainy all year)- monsoon (> 6 months rainy)- savanna (< 6 months rainy)

Mesothermal [C] ( subtropics / mid-latitude Mesothermal [C] ( subtropics / mid-latitude mild wintermild winter))- humid subtropical (hot summers)- marine west coast (warm to cool summers)- Mediterranean (dry summers)

Microthermal [D] (mid / high latitude Microthermal [D] (mid / high latitude cold wintercold winter))- humid continental (hot to cool summers)

Tropical [A] (tropical latitudes mild year round)Tropical [A] (tropical latitudes mild year round)- rain forest (rainy all year)- monsoon (> 6 months rainy)- savanna (< 6 months rainy)

Mesothermal [C] ( subtropics / mid-latitude Mesothermal [C] ( subtropics / mid-latitude mild wintermild winter))- humid subtropical (hot summers)- marine west coast (warm to cool summers)- Mediterranean (dry summers)

Microthermal [D] (mid / high latitude Microthermal [D] (mid / high latitude cold wintercold winter))- humid continental (hot to cool summers)

Climate Classification CategoriesClimate Classification CategoriesClimate Classification CategoriesClimate Classification Categories

Letters Letters refer to refer to Koppen Koppen SystemSystem

Deserts [B] (permanent moisture deficits)Deserts [B] (permanent moisture deficits) - arid deserts (tropical and midlatitude)

Deserts [B] (permanent moisture deficits)Deserts [B] (permanent moisture deficits) - arid deserts (tropical and midlatitude)

Tropical - Rain Forests [AfAf]

Tropical - Rain Forests [AfAf]

Tropical - Monsoon Climates [AmAm]

Tropical - Monsoon Climates [AmAm]

Tropical - Savanna Climates [AwAw]

Tropical - Savanna Climates [AwAw]

Mesothermal - Humid Subtropical [CfaCfa] (Hot-Summer

Climates)

Mesothermal - Humid Subtropical [CfaCfa] (Hot-Summer

Climates)

Mesothermal - Marine West Coast [CfcCfc] (southern hemisphere)

Mesothermal - Marine West Coast [CfcCfc] (southern hemisphere)

Mesothermal – Mediterranean [Cwb-aCwb-a] (dry

summer)

Mesothermal – Mediterranean [Cwb-aCwb-a] (dry

summer)

Microthermal - Humid Continental [Dfa-waDfa-wa] (hot summer

climate)

Microthermal - Humid Continental [Dfa-waDfa-wa] (hot summer

climate)

Desert - Midlatitude [BWkBWk] (cool desert climate - arid)

Desert - Midlatitude [BWkBWk] (cool desert climate - arid)

Things to know:Things to know:Things to know:Things to know: How do Arizona’s monsoons work to give How do Arizona’s monsoons work to give

us rain in the summer?us rain in the summer? Arizona receives rain from frontal systems in

the winter (already covered this earlier) Know the two major components of climate:

temperature and precipitationtemperature and precipitation The two controls onThe two controls on temperature temperature Two reasons for aTwo reasons for a dry season dry season Three reasons for aThree reasons for a wet season wet season Example locationslocations of the climate

classification categories covered, why they are dry and why they are wet, and why they have large variations or little variation in temperature

How do Arizona’s monsoons work to give How do Arizona’s monsoons work to give us rain in the summer?us rain in the summer?

Arizona receives rain from frontal systems in the winter (already covered this earlier)

Know the two major components of climate: temperature and precipitationtemperature and precipitation

The two controls onThe two controls on temperature temperature Two reasons for aTwo reasons for a dry season dry season Three reasons for aThree reasons for a wet season wet season Example locationslocations of the climate

classification categories covered, why they are dry and why they are wet, and why they have large variations or little variation in temperature Help: Chapter CS