Chapter 4: Weather & Climate

• Defining weather & climate• Controls of weather & climate

– Solar energy/latitude– Land and water distribution– Landform barriers– Atmospheric pressure– Wind systems– Elevation

• California’s Seasonal Changes• California’s Climate Zones• Climographs

Distribution of solar energy annually

The differential heating of land and water

• Landform barriers and weather; orographic precipitation

• Pressure and stability/instability

• Global pressure and wind system

• Upper Level Inversion

What is Smog?

• Ozone (O3) - invisible, irritates, impairs breathing

• Nitrogen Dioxide (NO2) - brown, impairs breathing

• Carbon Monoxide (CO) - invisible, reduces bloods oxygen

• Particulate Matter under 10 microns (PM10) - invades deep into lungs, reduces visibility

Ozone Formation

• product of solar energy and photochemical reactions.

• highest concentrations occur when sunlight is most intense.

• reaches peak levels during the middle of the day in the summer months.

• these types of air pollution patterns are called diurnal and seasonal variations

Ozone• one of the most important air

pollutants affecting human health.• Ozone (O3) is a molecule built of three

atoms of oxygen linked together in a very energetic combination.

• comes into contact with a surface it rapidly releases this extra force in the form of chemical energy.

• When this happens in biological systems, respiratory tract, can cause damage to sensitive tissues.

AQI 0-50 Good51-100 Moderate 101-150 Unhealthy for sensitive

groups151-200 Unhealthy200+ Very Unhealthy

• California Summer– East Pacific (Hawaiian) High– California Current, Advection Fog– Catalina Eddy– Summer Storms

• California Autumn– Weakening of Pacific High– Interior Cooling– Winds

• California Winter– Aleutian Low, Mid-Latitude Cyclones– Variability– Radiation Fog

• California Spring– Interior heating– Pacific High strengthening

• BSh—semi-arid, hot summer Csa—Mediterranean, hot summer

• BWh—arid, hot summer Csb—Mediterranean, mild summer

• Csbn—Mediterranean, cool summer w/fog

• World’s Mediterranean Climates

• World’s Deserts