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Atmospheric Heating, Moisture, Stability

Earth ScienceChapter 16: p. 454-460Chapter 17: p. 466-473

Weather instrument

shelter

North America isotherms Temperature comparisonVancouver, Winnepeg

Temperature comparisonQuito, Guayaquil

Temperature comparisonEureka, NYC

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Temperature comparisonSeattle, Spokane Cloudy day

Cloudy night January temperature

July temperature Jan and July temps

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DownpourLatent heat of water

Frost on window Relative humidity—constant temperature

Relative humidity—lowering temperature Humidity-temperature daily trend

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Dew on spiderweb Sling psychrometer

Changes in temperature with change in elevation

• Two different mechanisms– Earth’s atmosphere is heated from below– Gases cool as they expand

Earth’s atmosphere is heated from below

• It is warmer closer to the sea level• It is cooler at higher altitudes• Environmental lapse rate

– About 6.5o C / 1000 m– About 3.5o F / 1000 ft

Gases cool as they expand

• Still have same heat energy• Take up larger volume• Increase in volume at lower pressure• Atmospheric pressure declines with altitude• Temperature change due to change in

volume called “Adiabatic lapse rate”

Adiabatic lapse rate

• Temperature declines with lower pressure, at higher altitude

• Temperature increases with higher pressure, at lower altitude

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• Rate of temperature change depends on saturation

• Saturated air has condensation of water, which releases heat: warms environment

10o C / 1000 m if not saturated5o C / 1000 m if condensation is occurring

Adiabatic lapse rate Cooling by lifting—adiabatics

Orographic lifting Rain shadow

Warm front lifting Convergent lifting

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Tropical Convergence Convective lifting

Hot air balloons Stable conditions

Absolute instability Conditional stability

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Inversion Layer—Los Angeles Surface inversion

Inversion aloft Cloud classification—right

Cloud classification—left cirrus

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Cirrocumulus Cirrostratus

Altocumulus Altostratus

Nimbostratus Cumulus

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Cumulonimbus Fog—Golden Gate Bridge

Fog—Tule Fog Condensation in clouds

Bergeron notes Bergeron Process of ice-crystal growth

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Collision coalescence

Glaze ice

Giant hailstone Hail damage

Rime ice Pogonip

http://grannysatticquilts.com/pogonip.html

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Precipitation measurement Weather radar display