Topic-2-Precipitation.pdf

HYDROLOGY TOPIC 2: PRECIPITATION Prepared by Sir O  Precipitation refers to any form of water, liquid or solid, that falls from the atmosphere and reaches the Earth's surface. It is a vital...

HYDROLOGY TOPIC 2: PRECIPITATION Prepared by Sir O  Precipitation refers to any form of water, liquid or solid, that falls from the atmosphere and reaches the Earth's surface. It is a vital component of the Earth's water cycle and has a significant impact on various natural processes and human activities. Precipitation can occur in different forms, such as rain, snow, sleet, and hail, depending on the atmospheric conditions. PRECIPITATION  1. Air Masses and Fronts-The collision of different air masses with varying temperatures, humidity levels, and densities can lead to the lifting of warm, moist air, resulting in condensation and precipitation along fronts (boundaries between air masses). PRECIPITATION IS INFLUENCED BY A COMPLEX INTERPLAY OF VARIOUS ATMOSPHERIC AND ENVIRONMENTAL FACTORS. THESE FACTORS CAN VARY IN DIFFERENT REGIONS AND CAN HAVE SIGNIFICANT IMPACTS ON THE TYPE, AMOUNT, AND DISTRIBUTION OF PRECIPITATION. SOME OF THE KEY FACTORS THAT INFLUENCE PRECIPITATION INCLUDE:  2. Temperature and Humidity: Warm, moist air can hold more water vapor than cold air. When moist air is cooled, such as when it rises over mountains or encounters cold fronts, it reaches its dew point and water vapor condenses, forming clouds and precipitation. PRECIPITATION IS INFLUENCED BY A COMPLEX INTERPLAY OF VARIOUS ATMOSPHERIC AND 3. Topography: Mountains can force air to rise, cool, and ENVIRONMENTAL FACTORS. condense, leading to increased precipitation on windward sides THESE FACTORS CAN VARY IN (wind-facing slopes) and a rain shadow effect on leeward sides DIFFERENT REGIONS AND CAN (rain-shadow areas are drier due to descending air). HAVE SIGNIFICANT IMPACTS ON THE TYPE, AMOUNT, AND DISTRIBUTION OF PRECIPITATION. SOME OF THE KEY FACTORS THAT INFLUENCE PRECIPITATION INCLUDE:  4. Winds and Air Circulation: Atmospheric circulation patterns, such as the movement of air masses and prevailing winds, can determine where moisture-laden air converges and rises, leading to areas of increased precipitation. 5. Ocean Currents: Ocean temperatures and currents influence the evaporation rate, moisture content, and heat exchange between PRECIPITATION IS INFLUENCED the ocean and the atmosphere, which in turn affects precipitation BY A COMPLEX INTERPLAY OF patterns over adjacent land areas. VARIOUS ATMOSPHERIC AND ENVIRONMENTAL FACTORS. 6. Global Climate Patterns: Large-scale climate phenomena like El THESE FACTORS CAN VARY IN Niño and La Niña can influence ocean temperatures and DIFFERENT REGIONS AND CAN atmospheric circulation patterns, leading to shifts in precipitation HAVE SIGNIFICANT IMPACTS ON patterns around the world. THE TYPE, AMOUNT, AND DISTRIBUTION OF PRECIPITATION. SOME OF THE KEY FACTORS THAT INFLUENCE PRECIPITATION INCLUDE:  7. Anthropogenic Factors: Human activities, such as urbanization and deforestation, can alter local microclimates and influence precipitation patterns through changes in land use and surface properties. 8. Aerosols and Pollution: Airborne particles and pollutants can PRECIPITATION IS INFLUENCED BY A COMPLEX INTERPLAY OF act as cloud condensation nuclei, affecting cloud formation and VARIOUS ATMOSPHERIC AND altering precipitation patterns. ENVIRONMENTAL FACTORS. THESE FACTORS CAN VARY IN DIFFERENT REGIONS AND CAN HAVE SIGNIFICANT IMPACTS ON THE TYPE, AMOUNT, AND DISTRIBUTION OF PRECIPITATION. SOME OF THE KEY FACTORS THAT INFLUENCE PRECIPITATION INCLUDE:  PRECIPITATION general term for all forms of moisture emanating from the clouds and falling to the ground from the time of its formation in the atmosphere until it reaches the ground Drizzle Rain Snow Hail consists of drops under greater than 0.02 precipitation in the is precipitation in 0.02in diameter inches, drops greater form of ice the form of ice balls than 0.25 in diameter crystals resulting over 0.2 in tends to break up from deposition diameter 7  MEASUREMENT OF PRECIPITATION All form of precipitation are measured on the basis of the vertical depth of water that would accumulate on a level surface if the precipitation remained where it fell. Standard Tipping Weighing Precipitation gage bucket type gage  RAIN GAUGE MAP OF THE PHILIPPINES (DOST- PAGASA) TYPE OF CLIMATE IN THE PHILIPPINES  AVERAGE RAINFALL ARITHMETIC METHOD- The arithmetic-mean method is the simplest method of determining areal average rainfall. It involves averaging the rainfall depths recorded at a number of gages. This method is satisfactory if the gages are uniformly distributed over the area and the individual gage measurements do not vary greatly about the mean σ 𝑃𝑁 𝑃𝑎𝑣𝑒 = 𝑁  AVERAGE RAINFALL THIESSEN POLYGON METHOD- The relative weights for each gage are determined from the corresponding areas of application in a Thiessen polygon network, the boundaries of the polygons being formed by the perpendicular bisectors of the lines joining adjacent gages σ 𝐴𝑁 𝑃𝑁 𝑃𝑎𝑣𝑒 = σ𝐴 TYPHOONS (REPORTING) YOLANDA REPORT ABOUT ITS: ONDOY TRAJECTORY (PROVINCES NA DINAANAN) DURATION SENDONG STRENGTH (FROM LOW TO HIGH) ROSING DAMAGES AND CASUALTIES (ECONOMIC, STRUCTURES AND DEATHS) RUPING PABLO FRANK REMING LAWIN