Hydrologic Cycle
97.2 ocean
2.15 glaciers
.62 ground water
FW lakes, saline lakes, soil moisture, atmosphere, stream channels hold the rest.
Atmosphere and stream channels does the most damages
River
Flat terrain
Agriculture
Body of water in motion
Clearly defined passage ways
Carries water, sediment, nutrience
River Drainage Basins and Divide
Area drained by the system
The drainage divide
3 River Types
Straight
head waters
velocity is high, very fast flowing
Braided
interchangeably channels of water
not a lot of vegetation
glaciers
can carry huge amount of sediment
Meandering
Winds back and forth
Cup bank – velocity is the fastest
Point bars on the inside – slow velocity
Oxbow lakes – when a new channel is formed
Hydrologists – scientists investigating how width, depth, velocity, and discharges are related
^ width = ^ discharge
^ depth = ^ discharge
^ velocity = ^ discharge
^ velocity = ^ particle size that can be carried
*
* Sediment transport
can be carried as the suspended load
speed of the water dictate what particles it carries
cannot be eroded
*
Stream flow Equation
Q = a x v
Allows you to predict flowing
To build things distance
Q = discharge= the volume of water a river can carry per unit time ( ex: ft3/sec)
V = velocity= the speed at which the river flowing (ft/sec)
A = cross-sectional river area (ft2)
Floods
The point at which the water over the bank
Predictable – getting better at not killing people
Buildings and damage are not getting saved
“Hydrograph”
discharge and time
hydrographs change with degree of infiltration
in forest – 80-100% are in ground water…only 0-20% go in the river slowly
in ciry – 0-10% go into the ground (because ground is paved)…90-100% go into the stream quickly
flash flood!
Infiltration – water traveling into the ground and becoming part of groundwater
Degree of urbanization
The more “urbannes”, the less infiltration
Antecedent soil...