Moisture and precipitation distribution governs life in the tropics. Surplus heating and rising motion in the tropics ignites the global water and energy cycles and influences weather in the midlatitudes. This chapter presents the horizontal and vertical distribution of water vapor, tropical cloud formation and distribution, the lifecycle and precipitation characteristics of tropical mesoscale convective systems, and the variability of tropical precipitation on yearly, seasonal, and hourly time-scales.
At the end of this chapter, you should understand and be able to describe:
Why water vapor is important to weather and climate in the tropics
The range and distribution of water vapor content in the tropics
The distribution of evaporation and evapotranspiration rates in the tropics
The formation of tropical clouds by convection
The general pattern of cloud distribution in the tropics
The typical profiles of potential temperature and equivalent potential temperature in the tropical atmosphere
How the Saharan Air Layer and other dry intrusions changes the vertical distribution of moisture thermodynamic energy
The concept of moist and dry static (thermodynamic) energy and its vertical distribution in the tropics
How the vertical distribution of moist static energy varies with different modes of convection
The differences between convective and stratiform rain in tropical mesoscale convective systems
The effects of continental and maritime aerosols on tropical precipitation
The geographic distribution of annual tropical precipitation and its variability
The factors that influence the geographic distribution of tropical precipitation
The seasonal distribution of precipitation in the tropics and unique regional patterns
The differences between the diurnal cycle of tropical precipitation over land and over ocean, including the influential factors
Unique characteristics of the diurnal cycle during the equatorial transition seasons (spring and autumn)
The factors that influence the amount and location of rainfall on yearly and multi-year time scales
You should also be able to identify and describe:
The factors that influence evaporation and evapotranspiration rates
The dominant cloud types in the tropics
The typical zonal and meridional distribution of cloud depth over the tropical oceans
tropical meteorology, Distribution of Moisture and Precipitation, tropical moisture, tropical precipitation, global rainfall, interannual variability of precipitation, seasonal precipitation, tropical desert, evaporation, evapotranspiration, condensation nuclei, maritime aerosol, continental aerosol, convective precipitation, stratiform precipitation, cumulus convection, cumulonimbus, surface specific humidity, clausius-clapeyron, precipitation processes in cumulonimbus, variability of tropical precipitation, El Nino, MJO, ENSO, Hadley Cell, ITCZ, upwelling, evaporation minimum, monthly precipitation, orographic precipitation, warm rain, cold rain, collision-coalescence
February 15 2016: HTML and media assets in this lesson have been updated for current browsers and mobile devices. All links external to COMET's MetEd site have been checked and updated.
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