climate of sierra nevada

7/31/2019 Climate of Sierra Nevada

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Climate and Natural Life of the

Sierra Nevada


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General Climate Types of the Sierra Nevada


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Climate Variation in the Sierra Nevada

B - Dry/Desert Climates These are arid regions where annual evaporation exceeds annual

precipitation. There are two main subclasses: BS - semi-arid Steppe climateswhere precipitation is at least half of potential evaporation; and, BW - truedesert climates where precipitation is less than half of potential evaporation.

BWh - Hot Desert. This the climate zone of the Mohave Desert and only touches the

eastern base of the Sierra Nevada. It is characterized by extremely hot dry summers(average temperature of warmest month > 28C (82.4F)) and dry mild winters. AltitudeRange: Below 3,500 ft. Vegetation: Creosote scrub is typical of the Mohave Desert

.Bsh - Hot Steppe. Average temperature of coldest month > 0C (32F). This climate zoneforms a narrow band along the eastern base of the Sierra Nevada as well as the lowestfoothills on the western edge of the southern Sierra. It is similar to BWh, with theexception that it is marginally cooler and experiences slightly higher precipitation.

Altitude Range: East Side: 3,500-5,000 ft. West Side < 500 ft. Vegetation: East Side:Joshua Tree scrub and Creosote scrub are common vegetation types. West Side: Annualgrasslands.

Bsk - Cool Steppe. Average temperature of coldest month < 0C (32F). This climate zoneforms a narrow band along the steep eastern slopes of the Sierra Nevada just aboveBsh. There is no analog on the western slope. Altitude Range: 5,000-7,000 ft.Vegetation: Joshua Tree scrub (at the very southern end) and pinyon-juniper woodlandare common vegetation types.


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General Climate Types of the Sierra

Nevada


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C - Temperate/Mediterranean Climates In California, these are the areas of Mediterranean type climate, with

the average temperature of the coldest month < 18C (64.6F) and > -3C (26.6F), and the average temperature of the warmest month>10C (50F). Precipitation occurs primarily between October andApril, with little or no rainfall during the summer months.

Csa - Hot Summer Mediterranean. Characterized by hot dry summers, withthe average temperature of the warmest month > 22C (71.6F). Winters aremild and very little snow falls in this climate zone. Altitude Range: Valleyfloor to 2,000-3,000 ft. Vegetation: This is the blue oak/diggerpine/chaparral zone of the Sierra foothills.

Csb - Cool Summer Mediterranean. Characterized by warm to pleasant drysummers, with the average temperature of the warmest month < 22C

(71.6F). Winter precipitation is a mix of snow and rain. Altitude Range:2,000-3,000 ft to 6,000-7,000 ft. Vegetation: This is the ponderosa pine beltof the Sierra Nevada. Sugar pine and incense cedar are common. Black oak iscommon in the lower portions of this zone. White fir is common in the higherportions of this zone.


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Nevada


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D - Boreal/Microthermal (cold) Climates These areas are characterized by severe winters and heavy snowfall,

with the average temperature of the coldest month < -3C (26.6F)and the average temperature warmest month > 10C (50F). Theseclimates occur only in the higher areas of Sierra Nevada, typicallyabove 6,000-7,000 ft.

Dsb - Lower Boreal. Pleasant dry summers, cold snowy winters. Averagetemperature of each of the four warmest months > 10C (50F); temperatureof warmest month below 22C (71.6F). Altitude Range: Typically above6,000-7,000 ft. to near the timber line at 9,000-10,000 ft. Vegetation:Typified in the Sierra Nevada by the lodgepole pine/red fir association,though the ponderosa pine/sugar pine/white fir association is common atthe lower reaches of this climate. Jeffrey pine is common on the east side of

the Sierra. Dsc - Upper Boreal. Cool dry summers (with occasional thunderstorms), very

cold snowy winters. Average temperature of less than four months >10C(50F); temperature of warmest month below 22C (71.6F). Altitude Range:Typically from near the timber line at 9,000-10,000 ft. to about 12,000 ft.Vegetation: Typified in the Sierra Nevada by whitebark pine and limber pineand by the treeless alpine zones above the timber line.


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Nevada


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E - Polar/Alpine Climates These areas are characterized by extremely severe winters and cool

summers where the average temperature of the warmest month

climate of sierra nevada

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