1. © Oxford University Press, 2008. All rights reserved. 1 Chapter 5 CHAPTER 5 HYDROLOGIC SYSTEMS AND ATMOSPHERIC PROCESSES

2. © Oxford University Press, 2008. All rights reserved. 1 Chapter 5 INTRODUCTION Water is a unique substance The hydrologic cycle Precipitation Evaporation Transpiration Sublimation Runoff and infiltration Changes of state of water

3. © Oxford University Press, 2008. All rights reserved. 1 Chapter 5 MOISTURE IN THE ATMOSPHERE Latent heat of evaporation Defining saturation Spatial distribution in Australia Descriptions of atmospheric moisture –Relative humidity –Mixing ratio

4. © Oxford University Press, 2008. All rights reserved. 1 Chapter 5 CLOUD FORMATION Formation requirements –Water vapour –Nucleation –Trigger mechanisms –Is cloud seeding effective to create rain?

5. © Oxford University Press, 2008. All rights reserved. 1 Chapter 5 BASIC THERMODYNAMICS Definitions Lapse rates (dry, wet) The role of saturation Calculation of cloud location using T and T d

6. © Oxford University Press, 2008. All rights reserved. 1 Chapter 5 ESTIMATING ATMOSPHERIC STABILITY Adiabatic lapse rates versus background atmospheric temperature Estimating states of stability –Absolutely unstable –Conditionally unstable –Stable Inversions

7. © Oxford University Press, 2008. All rights reserved. 1 Chapter 5 TRIGGER MECHANISMS Convection Orographic Frontal Others

8. © Oxford University Press, 2008. All rights reserved. 1 Chapter 5 CLOUD DROPLET FORMATION AND GROWTH Condensation around nuclei Collision/coalescence Wake capture The importance of convection and turbulence Identifying cloud types Altocumulus lenticularis cloud formation

9. © Oxford University Press, 2008. All rights reserved. 1 Chapter 5 DEW AND FOG Dew and frost formation Fog formation and types –Radiation –Advection –Steam –Upslope –Global frequency distribution –Fogwater as a resource

10. © Oxford University Press, 2008. All rights reserved. 1 Chapter 5 SYNOPTIC AND REGIONAL PRECIPITATION Fronts and frontal theory –Types of fronts –Lifecycle in Australia –The influence of upper tropospheric waves –Consequences Squall lines Thunderstorms

11. © Oxford University Press, 2008. All rights reserved. 1 Chapter 5 THUNDERSTORMS AND THEIR HAZARDS Scale of thunderstorm systems Initial formation Mature stage Old age The role of the jet stream Hazards –Hail –Lightning –Downbursts and microbursts –Tornadoes

12. © Oxford University Press, 2008. All rights reserved. 1 Chapter 5 TORNADOES Definition Conditions for formation Spatial and seasonal distributions Fujita destruction scale

13. © Oxford University Press, 2008. All rights reserved. 1 Chapter 5 PRECIPITATION DISTRIBUTION Northern Australia Global