Khang Nguyen&

Hung PhamEarth Science Period 2

• Temperatures in California• Temperature Range• Climate Zones• Rainfall• Rain-Shadow Zones• Cold Fronts• The “Pineapple Express”• Annual Precipitation• Wild Fire• Tule Fog• May Gray/June Gloom• Earthquake Weather

The temperature gradient between immediate coast and low-lying inland valleys in the south is about 7 °F (4 °C) in winter and in summer roughly 25 °F (14 °C).

Palm Springs, a city in the Coachella Valley, averages high/low/mean temperatures of 75°F/50°F/63°F, (24°C/10°C/17°C) respectively during the period of cooler weather form Nov. to Apr.

At the Santa Monica coast, the average high in August is 75 °F (24 °C), while in Burbank, approximately 10 miles (16 km) inland, the average high in August is 90 °F (32 °C); a temperature gain over one degree per mile.

The temperature gradient is most extreme between Santa Barbara and Death Valley, with temperatures between the two differing by 4 °F and 35 °F (2 °C and 20 °C) in the winter and summer.

• The topography in California and California’s location near the Pacific Ocean have created

diverse climate patterns in the

state. The climate in California ranges from cool and wet

to hot and dry. Rainfall patterns have a large impact on California’s Climate.

• The two air masses that most often cause rain in California during the winter are shown in the picture.

• These air masses are the Maritime Polar Pacific air

mass and the Maritime Tropical Pacific air mass.

• As these air masses enter the mid-latitudes, they are driven across the Pacific Ocean toward California by the winds of the prevailing westerly.

• As these air masses move over the Pacific Ocean, they absorb moisture from the evaporation of ocean water.

• The California Coast Ranges and the Sierra Nevada create rain-shadow zones. Rainfall is heavy along the western side of the Coast Ranges and the Sierra Nevada. Much less rain, however, occurs on the eastern side of these mountains. Thus, semi-arid interior valleys and arid deserts have formed on the eastern side of the mountains.

• As Maritime Polar Pacific air mass moves southeast toward California in the winter, the air mass meets warmer air from the mid-latitudes.

• The air mass pushes the warm air upward and forms a cold front.

• Rain often begins to fall over the Pacific Ocean

before the cold front reaches the California Coast.

• If rain does not begin over the ocean, then mountains will determine where rain will occur in inland California.

• Along a cold front, conditions that cause a low-pressure, counter clockwise circulation of the atmosphere may develop.

• The southern part of this circulation pattern produces southwesterly winds.

• As these winds move father southward, they pull air from the Maritime Tropical Pacific air mass into southern California.

• The result is warm, tropical rain in southern California. The name “Pineapple Express” refers to this warm, moist air that comes from the Pacific Ocean near Hawaii.

• Westerly winds from the oceans also bring moisture, and the northern

parts of the state generally receive higher annual rainfall amounts

than the south.

• Northwestern California has a temperate climate with rainfall of 15

inches (380 mm) to 50 inches (1,300 mm) per year. Some areas of

Coast Redwood forest receive over 100 inches (2,500 mm) of

precipitation per year.

• The Central Valley has a wide range of precipitation.

• The northern parts of the Central Valley receive substantially greater

precipitation from winter storms which sweep down from the Pacific

Northwest, while the southernmost regions of the Central Valley are

near desert-like because of a lack of precipitation.

• Parts of the Valley are occasionally filled with thick fog.

• The high mountains, including the Sierra Nevada, the Cascade Range, and the

Klamath Mountains, have a mountain climate with snow in winter and mild to

moderate heat in summer.

• On the east side of the mountains is a drier rain shadow. California's desert

climate regions lie east of the high Sierra Nevada and Southern California's

Transverse Ranges and Peninsular Ranges.

• The low deserts east of the southern California mountains, including the Imperial

and Coachella valleys and the lower Colorado River, are part of the Sonoran

Desert, with hot summers and nearly frostless mild winters; the higher elevation

deserts of eastern California, including the Mojave Desert, Owens Valley, and the

Modoc Plateau, are part of the Great Basin region, with hot summers and cold

winters .

• Summers are typically hot and dry, particularly in the southern areas.

• This makes them prone to wildfires. • These can be life threatening and cause

evacuation. • Wildfires are less common along the coast

because of the cool humid summers, but can occur in autumn when the Marine layer is less common making it warm and dry.

• This is the 2nd Largest Wild Fires In California.

• A thick ground fog that settles in the San Joaquin Valley and Sacramento Valley areas of the California Central Valley.

• Tule fog forms during the mid fall, winter to early spring after the first significant rainfall.

• This phenomenon is named after the Tule grass wetlands of the Central Valley.

• Tule fog can extend from Bakersfield to Chico. • Accidents caused by the Tule fog are the leading

cause of weather-related deaths in California; visibility is usually less than an eighth of a mile (about 600 feet or 183–200 m), but can be less than 10 feet (3 m).

• This here is a Tule Fog covering the paradise at dawn.

• A characteristic weather pattern of late spring (May and June) in which a combination of inland heat, off-shore cool water, and prevailing wind patterns bring foggy and overcast weather to coastal regions. From Point Conception northwards the gloom continues until early autumn.

• This was over LA where the

“May Gray/June Gloom” happened.

• Any unseasonal, uncomfortable weather, typically hot and more humid than usual, and often associated with high and mid-level clouds, is spoken of (usually jokingly) as "earthquake weather”.

• http://en.wikipedia.org/wiki/

Climate_of_California#Temperaturerange

• http://www.city-data.com/states/California-

Climate.html

• Most information are gathered from Earth

Science book.