Definitions

- Hydrology is the geoscience that describes and predicts the occurrence, circulation, and distribution of water of the earth and its atmosphere.

- Hydrogen bonding - the attraction of H to an electronegative atom, such as nitrogen, oxygen, or fluorine, between the positive charges of one molecule (H) and the negatively charged end of another (O)

-Specific heat is the amount of heat energy required to raise the temperature of 1 gram of water 1°C

- latent heat is the energy absorbed or released during a change of state

- Temperature is a measure of the vibratory energy of the molecules

- Viscosity is the resistance of a liquid to motion.

• - A conservative quantity is one that cannot be created or destroyed within the system. (don't gain or lose in
• its just moves from one thing to the next)

- watershed is the area of land that drains water, sediment, and dissolved materials to a common outlet at some point along a stream channel.

- Time Series is a discrete sequence of values with each value assigned to a particular time in the sequence

- The flow duration curve is a plot that shows the percentage of time that flow in a stream is likely to equal or exceed some specified value of interest.

Radiation - process by which electromagnetic energy emits from an object; radiant energy flows out of all bodies, with temperature and nature of the surface of the objects playing a key role in radiation effectiveness.

Convection - the transfer of heat by a moving substance (opposite of conduction). --> convection oven

Conduction - the movement of energy from one molecule to another without changes in the relative positions of the molecules.

Convergent (extra-tropical and frontal) resulting from air being forced upward in a low pressure system (e.g. hurricane) or from the lifting of air masses along frontal boundaries; air pushed together has nowhere to go but up

Convective – resulting from convective lifting of an air mass. Convection is the circulatory motion that occurs in a fluid or gas at a non-uniform temperature owing to the variation of its density and the action of gravity

Orographic – resulting from the lifting of air masses due to topography

1.Magnitude – amount of rain

2.Intensity – rainfall per unit of time e.g inches per hour, inches per day, inches per year

3.Duration – how long the rainfall event of interest lasts or the period of rainfall we are interested in

4.Frequency – how often an event occurs (e.g. a specific amount or amount per unit of time)

Drizzle Rain Ice Pellets (sleet) Freezing rain Snow Hail

Drizzle – fine mist with drop about 0.1 - 0.5 millimeters (0.004 – 0.02 in) low intensity

Rain – all liquid precipitation heavier than drizzle, average about 1 millimeter (0.04 in), intensities – light (<0.1in per hr), moderate (0.11 – 0.30 in per hr), heavy (> 0.30 in per hr)

Ice Pellets (sleet) – raindrops freeze as they fall when temperature is below freezing

supercooled rain that is falling on a frozen surface

Hail – 0.2 to 4 in are rounded lumps of ice

The latent heat of vaporization is the energy required to overcome the molecular forces of attraction between the particles of a liquid, and bring them to the vapor state, where such attractions are minimal.