Presentation on theme: "Clouds & Precipitation. Saturation vs. Air Temperature The actual amount of Water air can hold changes With air temperature Air at 104 F can hold 3 times."— Presentation transcript:
Saturation vs. Air Temperature The actual amount of Water air can hold changes With air temperature Air at 104 F can hold 3 times As much water as 68 F air ! (47 grams vs only 15 grams) Air at 68 F can hold 4 times As much water as air at 0 F (15 grams vs only 4 grams) 32 F 68 F 104 F 4 grams 15 grams 47 grams
Adiabatic Cooling: Clouds and Lifting Condensation Level (LCL) LCL / Cloud base = dew point altitude
CLOUDS A cloud is water vapor condensed around dust particles (condensation nuclei). At any given time, ~50% of Earth is covered by clouds and about 6% is having precipitation. The greater the amount of moisture in an air mass, the lower the level of condensation.
CONDENSATION > 0 o C = water droplets (lower levels) < 0 o C = ice crystals (upper levels) middle levels = mixture of ice and water
Type of cloud depends on… amount of moisture in the air degree of uplift atmospheric stability
NAMING CLOUDS 3 Basic types: Cirrus – curly or fibrous Stratus – means “layer”; flat and/or layered Cumulus – means “heap”; puffy or piled up The prefixes cirro (high), alto (middle) refer to the level in the atmosphere. The prefix nimbo means “rain-bearing”.
Lifting Mechanisms In order to make clouds, the air has to be lifted so that it will condense. Convection Frontal Cloud Orographic Uplift