GEOL 4220Exam # 1 Study GuideLecture 1 (Climate and Precipitation)1)Winda. Coriolis effect – bends the direction of the windb. Doldrums- air rising from the equator that moves north c. Westerlies- if you face the west, the wind is blowing at youi. Not the direction of the wind per sayd. Winds take form (temperature/humidity) of the land they are passing over2)Snowa. Snow forms to climate as well as windsi. Snow can be dry, wet, etc.3)***Stormsa. Convectional – warm air rising, cool air fallingi. Creates thunderstormsb. Frontal – cold air going over warm air OR warm air going under cold airi. Can tell difference by the types of clouds1. Warm air over cold air creates storms and come quickly resulting inincreased precipitationc. Orographic – masses of air pushed up by wind are forced up the side of mountainsi. Think sea to mountain storms. Moist air on sea side, dry air on other side of mountain. ii. Create rain shadows d. Base of mountains have half the rainfall then top of mountainse. What is the phenomena where air is lifted?i. Orographic 4)Humiditya. There is 100% humidity if the maximum amount of water is held in the atmospherei. In GA, humidity is almost always 100% - creating dewb. As air warms, humidity decreases because air can hold more water5)Precipitationa. How much do we measure precipitation?i. Depends on the type of measuring source used. Can be measured daily and hourly. b. What is a storm?i. A storm forms in response to an extreme difference in air pressure, drivenby the movement of warm and cold air. c. How much can it really rain?i. Extreme rainfall can occur but is often an outlier to the average annualprecipitation d. What is meant by a 100-year storm?i. Find max rainfall for each storm on an annual basis. Rank the biggest storms (based on probability- biggest has 1/100). Find the return period by flipping the fraction (100/1). This equals the probability of a 100 year storm. ii. Water year – starts Sep. first and ends Oct. 31st – tend not to have storms that cross that time period 6)Data Sources for Precipitationa. All rainfall is measured at a point b. Rainguage – measures precipitationi. Non recording – used in older days1. Collaborated so that areas collecting the rain produces an area of rain that is measured in depth2. Rainguage is measured at the same time every day3. Inaccurate data measurement because it is measured only once a day (doesn’t always rain all day)ii. Tipping bucket rainguage1. Every time the bucket is tipped, there is a read switch. Counts the number of tips over a period of time. You work out the rates. 2. 100 tips in an hour = a certain amount of precipitation3. Once rainfall is recorded, you can then measure intensity. c. How long does it have to not rain in order to call it a new storm?i. In GA, average is 7 hours of no rain for a new storm ii. Changes depending on locationiii. NCDN collets rainfall data internationally – daily and hourly7)Natural conditions and Distribution a. Droughts and extreme rain can cause natural fluctuations in a distribution b. Noah effect and Joseph effect – biblical explanation to statistical hydrology c. Different patterns for distribution occur in different parts of the country i. East coast – regular distribution1. Florida – more convectional storms in the summerii. Pacific coast 1. Opposite of east coasta. NW precipitation in form of snow 8)Groundwater – only care about one year for this. Rather precipitation is over many years.Lecture 2 (Infiltration and Runoff)1)Infiltration basicsa. Maximum infiltration rate can occur depending on the soil type b. Once the soil is infiltrated, water moves down through the unsaturated zone.c. Initially the soil is a mixture of both water and aird. Percolation- water moving downward e. Water table- the divide between the unsaturated zone and the saturated zonef. Groundwater is in the saturated zoneg. Baseflow- when the water table is above the earth and flow occurs on land (lakesand streams)i. Decreases with time until the system is filled with water 2)Hydrographa. Measures distance versus timeb. Can be subdivided into different components c. Has a rising limb, a peak, a recession limb, and baseflow d. All hydrographs are watershed specific – create different proportions i. Flashy watershed – hydrograph rises and falls quicklyii. Broad watersheds – have more subsurface flowiii. Hydrograph examples1. Total stream flow2. Hortonian Overland Flow- water occurring over a drainage basin when the rainfall intensity exceeds the infiltration ratea. Once there is saturation there is no more storageb. Can also be illustrated with the infiltration capacity curve 3. Baseflow- water in a river that comes from groundwatera. Should not be confused with groundwater 4. Direct Precipitation- water falling directly on the stream 5. Interflow- component of runoff where water flows at or near the surface without becoming part of the groundwater system 3)Hydraulic Conductivity a. Rate at which water can flow4)***Stream Types a. Gaining (Effluent)i. Typical of humid regions where groundwater recharges streamsii. All streams east of the Mississippib. Losing (Influent)i. Typical of arid regions where streams recharge groundwater c. Perennial streamsi. A stream that flows year roundii. Represented by solid blue lines on a mapd. Intermittent streamsi. Seasonalii. Flow only in the winter and early springiii. Once the water table drops, they stop flowingiv. Water table drop b/c of ET – plants need water to grow in spring and summer v. Represented by dotted blue line on a mape. Ephemeral streamsi. Flow only during a stormii. Never interacts with groundwater iii. Does not occur on a map – but can tell in ephemeral by contour lines5)Streamflow measurementsa. Water quality values change with streamflowi. If you are measuring water chemistry in a stream, always measure streamflow as wellb. To compare values, you must know what discharge is doing as wellc. Volume per unit time – used to measure streamflowd. Types of measurement graphsi. Average daily flow – take data throughout the day and average it1. Log average daily flow – more normally distributed2. More interested in low flows than high flows – creates problems with groundwater as well as surface water3. Streamflow is different every day for any given streamii. Flow duration curve – summarizes data for a stream 1. Take range of flow on a log scale and divide that into about 20 areas (he calls it