Flood Frequency Analysis - Gumbel Method
Flood Frequency Analysis is the statistical calculation of the probability of occurrence of flood of specific magnitude in a river, the specific period is called return period and the flow can be ranked as maximum possible flow. In Hydrology flow frequency analysis has occupied anTypes of Air Masses and Fronts
If the surface is warm and moist, air in the region becomes warm and moist also. If the air then moves to different regions it takes these properties along, gradually changing in response to the new area. Air masses are designated as cold or warm and moist or dry. It is a boundary between two air masses. The term has its origins analog to military operations as theTypes of Precipitation Formation Processes
Although moisture is always present in the atmosphere but it is condensed only when air is cooled and saturated with some water vapors. Usually mechanism by which air is cooled to cause precipitation is the lifting of air mass. Based on lifting of air carrying vapors, precipitation is classified as follows: Cyclonic precipitation Convective precipitation Orographic precipitationSources of Error in Measuring Precipitation
Some water is used to wet the surface of instrument. The rain recorded may be less than the actual rainfall due to the direction of the rainfall as affected by wind. Dents in the collector and tube may also cause error.Types of Precipitation Based on Lifting Mechanism
Although moisture is always present in the atmosphere but it is condensed only when air is cooled and saturated with some water vapors. Usually mechanism by which air is cooled to cause precipitation is the lifting of air mass. Precipitation is often classified according to the factor responsible for lifting of air to higher altitudes. Following are the various types of
Clear Water Scour Scouring in Hydraulic Structures
Local scour is the Erosion occurring over a region of limited extent due to local flow conditions, such as may be caused by the presence of hydraulic structures. Scour is the result of the erosive action of flowing water excavating and carrying away material from the bed and banks of streams. Potential scour can be a significant factor in the analysis of a stream crossing system.
