T r o p o s p h e r e $_{ }$S t r a t o s p h e r e M e s o s p h e r e T h e r m o s p h e r e E x o s p h e r e  Ozone lay er T r o p o p ause Figure 9-5.  Layers of the atmosphere. 10 000 1 000 100 10 1 0.1 General circulation   monsoon circulation Jet stream Occluded front  hurricane  Land/sea breeze   lee wave Thunderstorm   downburst Tornado  dust devil   thermal  turbulence second minute hour day week month year Space scale (NM) Time scale (lifetime) Standard Atmosphere A A B C D E F B C D E F Microscale Macroscale Mesoscale Figure 9-6.  Scale of circulation—horizontal dimensions and life spans of associated weather events. Smaller scale features are embedded in larger scale features.  For instance  a microscale thermal may be just one of many  in a mesoscale convergence line  like a sea breeze front.  The sea breeze front may occur only under certain synoptic  (i.e.  simultaneous) conditions  which is controlled by the  macroscale circulations. The scales interact  with feedback  9-5