Observations of temperature, winds, and atmospheric trace gases suggest that the transition from troposphere to stratosphere occurs in a layer, rather than at a sharp ‘‘tropopause.’’ In the tropics, this layer is often called the ‘‘tropical tropopause layer’’ (TTL). We present an overview of observations in the TTL and discuss...
Aerosols and clouds have important effects on Earth's climate through their effects on the radiation budget and the cycling of water between the atmosphere and Earth's surface. Limitations in our understanding of the global distribution and properties of aerosols and clouds are partly responsible for the current uncertainties in modeling...