Measuring Weather PDF

Measuring Weather Weather Elements Weather elements are the basic properties that we use to measure and describe weather conditions. Weather Elements Temperature Precipitation Humidity Air Pressure Wind Speed Wind Direction Cloud Cover PM 10 / PM2.5 UV  Temperature: What it measu...

Measuring Weather Weather Elements Weather elements are the basic properties that we use to measure and describe weather conditions. Weather Elements Temperature Precipitation Humidity Air Pressure Wind Speed Wind Direction Cloud Cover PM 10 / PM2.5 UV  Temperature: What it measures: How hot or cold a place is. Unit: Degree Celsius (°C) or degree Fahrenheit (°F) Instrument used: Thermometer Remark: Fahrenheit (℉) is commonly used in America  Precipitation: What it measures: The amount of moisture that has fallen from the sky to the Earth’s surface (rain, snow, hail, sleet). Unit: millimetres (mm) or centimetres (cm) Instrument used: Rain gauge (Measures the depth of liquid in the rain gauge usually per hour.)  Air pressure: What it measures: The weight of air on the Earth's surface that creates a pressing down force. Unit: millibars (mb), commonly range from 970 mb to 1040 mb. Hecto-pascal (hPa) Instrument used: Barometer  (Absolute) Humidity: What it measures: the amount of water vapour in the air. Unit: (g/m³) Relative Humidity Relative humidity = The percentage between water vapour in the air and the capacity of retaining the water vapour in the air at a given temperature. Unit: percentage (%) Instrument used: Hygrometer  Wind direction: What it measures: The direction that the wind is coming from. Unit: compass directions (North, East, West, South, Northeast, Southeast, etc.) Instrument used: Wind vane, or a Wind sock.  Wind Speed: What it measures: How fast the wind is blowing Unit: miles per hour (mph) or kilometres per hour (kph) Instrument used: Anemometer. (How the wind is turning the cups and a dial shows the speed of the turns.)  Cloud Cover: What it measures: How much of the sky is covered by clouds from a particular location Unit: Oktas - Scale ranges from 0 (clear sky) to 8 (sky completely covered by clouds) Instrument used: Eyes (We only need to look at the sky, divide it mentally by 8, then estimate how many imaginary boxes can be filled by the amount of clouds at a particular location.)  PM10: What it measures: The concentration of tiny particles (10 micrometres or less) in the air. Unit: micrograms per cubic meter of air Instrument used: Optical Particle Counter. Stevenson Screen Thermometer Hygrometer Barometer  https://padlet.com/paris80/padlet-4qg75z0gq46q2ief Installing Weather Monitoring Stations Ship High Hills (High Altitudes) Major roads and bridges and Airport Residential and commercial areas Weather balloon Weather Weather Weather is the condition of the atmosphere … … Atmosphere The layer of the mixture of air that surrounds the Earth, and it is about 1,000 kilometres thick. The atmosphere (Troposphere) is where various weather phenomena occur. Characteristics of weather Characteristics of weather Weather Weather is the condition of the atmosphere of a specific place, which can change over a short period of time.  Extreme weather On September 3, the City L government issued a statement saying that ongoing thunderstorms caused flooding, submerging large parts of the streets and disrupting transportation. Data shows that in the past two days, City L and the surrounding areas received over 76 mm of rainfall. The average annual rainfall in City L is 120 mm. Extreme weather Extreme weather refers to unusually intense or abnormal weather phenomena. These events typically exceed the normal weather patterns for a given area and can have severe impacts on humans/society, economy, and the environment. Three types of impacts of extreme weather condition Social Impact: Harm to people Economic Impact: Financial losses. Environmental Impact: Damage to the environment. Thunderstorms An extreme weather condition often involve heavy rain, lightning, and thunder. Lightning ? Lightening ? Thunder? Lightning: This refers to a sudden flash of light caused by the discharge of electricity in the atmosphere during a storm. Lightening: something becoming lighter in weight or color. Thunder: Thunder is the loud sound that follows lightning. The atmosphere The layer of a mixture of gases that surrounds the Earth.  Exosphere Thermosphere Mesosphere Stratosphere Troposphere  decreases increases decreases increases decreases The reasons for the temperature trends in each layer The reasons for the temperature trends in each layer Troposphere: As altitude increases, the number of air molecules __________ due to _________, reducing the ability to retain heat……(as air molecules have the ability to retain heat) So the temperature decreases with height. The reasons for the temperature trends in each layer Troposphere: For every 1000 metres of ascent, the temperature decreases by about 6 degrees Celsius. The reasons for the temperature trends in each layer Stratosphere: = Ozonosphere (Ozone gas) UV (ultraviolet radiation) The reasons for the temperature trends in each layer Mesosphere: Similar to the Troposphere The coldest layer of all the layers. The reasons for the temperature trends in each layer Thermosphere: As altitude increases, N2, O2, and O are heated more efficiently by solar radiation. The hottest layer of all the layers. The reasons for the temperature trends in each layer Exosphere: Void of air molecules in the outer space. Not all scientists agree that the Exosphere is really a part of the atmosphere. Troposphere and Weather Hot air balloons _ Convection current Troposphere The circulation of the warm air rises and cold air sinks. Convection current -> Wind & Precipitation Wind Air sinks → high air pressure (exerts more force on the surface). _______→ low air pressure (exerts ______ force on the surface). Wind = air naturally moves from a high air pressure area to low air pressure area Convection current -> Wind & Precipitation Precipitation Hot air rises, it carries water vapour. Hot air reaches the upper troposphere, air is cooled, condensation occurs, and suspended water droplets group together to form clouds. Water droplets become too heavy for the atmosphere to support, they fall as rain. How is rain formed? Hot air rises… …... Water droplets fall as rain. YOUR TURN!!! The formation of the Weather Weather (Wind…Precipitation…) Convection current Warm air rises & Cold air sinks Some areas with higher temperatures & Some areas with lower temperatures Weather formation is the result of uneven heating of the Earth’s surface. How is weather formed? Weather formation is the result of … … Convection current Precipitation & wind YOUR TURN!!! Tropopause refers to the atmospheric boundary that separates the troposphere and the stratosphere where air stops to cool with increased altitude. Tropopause refers to the atmospheric boundary that separates the troposphere and the stratosphere where air stops to cool with increased altitude. YOUR TURN!!! Why does weather mostly occur in the Troposphere? Because the vast amount of water vapour is concentrated in the Troposphere because of gravity. In the above layer (Stratosphere) because the air is warmer as altitudes increase, so air contains a limited amount of water vapour, as a result, a lot of weather conditions will not happen in this layer. Why does weather mostly occur in the Troposphere? YOUR TURN!!! Why do airplanes quickly ascend to the stratosphere after takeoff? To avoid extreme weather conditions in the Troposphere like turbulence, rainstorms, and windstorms. Extreme weather conditions are formed by fast-moving air (wind) and (fast condensation of water vapour) which happens in the Troposphere. It is safer to fly in the Stratosphere instead of the Troposphere. Why do airplanes quickly ascend to the stratosphere after takeoff? YOUR TURN!!!  Part A 1. Macao Meteorological and Geophysical Bureau(1) / SMG(1) 2. Weather is the condition of the atmosphere(1) of a specific place(1), which can change over a short period of time(1). 3. a b c d e f Social Environmental Environmental Social Economic Social Because …… Therefore…… Rainstorms bring heavy rainfall to During flooding, ground-level retail stores Macau. However, due to the city's roads in low-lying areas may be submerged, and being mostly made of impermeable a large quantity of goods can be damaged concrete and the drainage system being by water. Store owners will need to spend inadequately designed, flash floods may a significant amount of money to restock occur in low-lying areas in Macau. their goods. During flooding, underground parking lots in low-lying areas may flood with a large amount of water, submerging and damaging the parked vehicles. Car owners will have to spend a substantial amount of money to repair the damaged vehicles. …Etc… …Etc… 5. The earth is a sphere, and the amount of solar radiation given out by the sun is always the same. At a lower latitude, the angle of the solar radiation entering the Earth is bigger, so a smaller area is receiving and sharing the same amount of solar radiation. As a result, the concentration of the heat energy is higher and the temperature is higher. It is the reason why a city at a lower latitude usually has a relatively higher temperature. Rubrics: If students mention the shape of the earth is a sphere, 1 points. If students mention the amount of solar radiation given out by the sun is always the same, 1 point. If students mention the angle of the solar radiation entering the Earth is bigger, 1 point. If students mention the size of area receiving the same amount of solar radiation is smaller, 1 point. If students mention the concentration of the heat energy is higher, 1 point. If students give the conclusion (temperature at lower latitude is higher), 1 point.  Part B exosphere Decreases thermosphere Increases mesosphere Decreases stratosphere Increases troposphere Decreases 2. As altitude increases, the number of air molecules decreases due to gravity. Air molecules can absorb or retain heat, so as the altitude increases, the decrease in air molecules leads to a reduced ability to retain heat, causing the temperature to drop. Rubrics: If students mention the number of air molecules decreases with height, 1 points. If students mention because of gravity, 1 point. If students mention air molecules can absorb or retain heat, 1 point. If students give out conclusion: so less amount of air molecules has less ability to retain heat, 1 point. 3. atmospheric boundary, cool 4. a. True b.hottest c. water droplets d. cooled e. uneven f. True g. 6°C To avoid extreme weather conditions in the Troposphere like (Turbulence, rainstorm, typhoon.) because extreme weather conditions are formed by fast moving air (wind) and fast condensation of water vapour), which happens in the troposphere. So it is safer to fly in the Stratosphere instead of the Troposphere. Rubrics: If students mention avoid extreme weather conditions in troposphere, 1 points. If students mention fast moving air, 1 point. If students mention fast condensation, 1 point. If students conclusion: safer to fly in the Stratosphere, 1 point. Part C anemometer Rain gauge Wind vane Optical Particle Counter Wind sock thermometer 2 How fast the air is moving. (1) The concentration of tiny particles in the air. (1) Temperature Air pressure Humidity Wind Speed - Degree Celsius ( ) Millibars (mb) Percentage (%) Kilometre per hour - Fahrenheit ( ) (km/h) Hecto-pascal (hPa) Mile per hour (mph) Stevenson Screen Thermometer Hygrometer_Barometer_ 6 A. 1.2 m from thermometer to ground 2 B. Louvres 1 C. White paint 4 D. Door faces north 5 E. Door lock on top 3 F. Double roof with lid Ship, high hills, major roads, major bridges, airport, residential and commercial areas, air balloon, satellite Global Atmospheric Circulation ④ At 60 degrees latitude, cold air from the poles and warm air ③ from 30 degrees collide -> two groups of air collide -> the It refers to the global High latitude (poles) → low temperature → air sinks group of lighter warm air is lifted by the group of cold air, → high air pressure -> Polar High-Pressure Belts while the heavier cold air sinks beneath the warm air - > low pattern of airflow. air pressure -> Subpolar Low-Pressure Belts ② The warm air rising at the equator moves horizontally Polar High-Pressure Belt towards higher latitudes and becomes cold (as they move towards the higher latitudes, air cools down) enough to Polar Easterlies sink around 30 degrees latitude → high air pressure -> Subpolar Low-Pressure Belt Subtropical High-Pressure Belts Westerlies The Relationship Between Weather and Pressure Belts: Subtropical High-Pressure Belt (Unstable) Heavy Equatorial Low- ① High temperature rainfall Northeast trades Pressure Belt Low latitude (equator) → high temperature (because Equatorial Low-Pressure Belt of higher concentration of solar radiation shared (Stable) Low/less Subtropical High- among a smaller area) → air rises → low air High temperature rainfall pressure -> Equatorial low-pressure belt Pressure Belts Southeast trades Subtropical High-Pressure Belt (Unstable) Heavy Subpolar Low- Low temperature rainfall Westerlies Pressure Belts Subpolar Low-Pressure Belt Cell is the circulation of the (Stable) Low/less Polar High- Polar Easterlies atmosphere, formed by the rising Low temperature rainfall warm air and sinking cold air. Pressure Belts Polar High-Pressure Belt Rainforests are mostly distributed along the equatorial low-pressure belt. The Coriolis force is a force caused by the Earth's rotation. Deserts are mostly distributed along the subtropical high-pressure belts. In the Northern Hemisphere, the wind is deflected to the right. Rainforests Deserts Right Right Right Right In the Southern Hemisphere, the wind is deflected to the left. Left Left Left Left Air pressure The relationship between air pressure and air movement The relationship between air pressure and air movement WHY? Your turn! high low high air pressure air pressure air pressure area area area A B C The relationship between air pressure and air movement Low air pressure area = where the warm air rises (high temperature)= exerts lower pressing down force onto the ground surface. High air pressure area = where the cold air _______ (______ temperature)= exerts ________ pressing down force onto the ground surface. Synoptic map (weather map) Which map does this map look similar to the one we studied before(F1)? Contour Map Contour line Height Synoptic map (weather map) Isobar Air pressure value （all spots on the same isobar line have the same air pressure） A map that summarizes the atmospheric conditions over a wide area at a given time. Synoptic map The units of air pressure:_____ L/H ?? The relationship between wind speed and the spacing of isobars Pressure gradient force The force that drives wind from high-pressure areas to low-pressure areas is called the pressure gradient force. Pressure gradient force Place A Wider isobars; A smaller difference in air pressure; ___________ pressure gradient force Gentle and slow wind. Place B Narrower isobars; A greater difference in air pressure; ___________ pressure gradient force Strong and fast wind. The relationship between air pressure and weather Low Air Pressure = Unstable Weather Warm air rises with lots of lower pressing down water vapour from the Low air pressure force ground surface Air cools down (the rising air is with lots of water vapour) Increases condensation Dew point Moist, cloudy, rainy, and unstable weather conditions Dew point Dew point A certain degree of temperature when the air becomes saturated with water vapour, and the condensation starts. To be more specific When air temperature decreases, its capacity to hold water vapour decreases; When the air temperature decreases to a certain temperature where the air can no longer hold its current moisture content, that certain temperature is called the dew point. (Then the condensation starts).  Saturated air?? The given temperature = 20°C Carrying capacity of Amount of water vapour in the Relative water vapour air humidity Group of air 30g 10g 10/30 = 33% Not yet saturated (A) Group of air 30g 20g 20/30 = 66% Not yet saturated (B) Group of air 30g 30g 30/30 = 100% Saturated (C) The air is saturated = cannot hold any more water vapour = Relative humidity is 100% Dew point Dew point A certain degree of temperature when the air becomes saturated with water vapour, and the condensation starts. To be more specific When air temperature decreases, its capacity to hold water vapour decreases; When the air temperature decreases to a certain temperature where the air can no longer hold its current moisture content, that certain temperature is called the dew point. (Then the condensation starts). The difference in water vapour capacity between warm and cold air The higher the temperature, the more water vapour the air can hold. The lower the temperature, the less water vapour the air can hold. Temperature Carrying capacity of water vapour W W W Group of air 10°C 10g (A) Group of air 20°C 30g (B) Group of air 30°C 50g (C) Dew point Dew point A certain degree of temperature when the air becomes saturated with water vapour, and the condensation starts. To be more specific When air temperature decreases, its capacity to hold water vapour decreases; When the air temperature decreases to a certain temperature where the air can no longer hold its current moisture content, that certain temperature is called the dew point. (Then the condensation starts).  Condensation and dew point Given: Group of air (A) ; the temperature is decreasing. Decreasing Carrying capacity of Amount of water vapour in the Relative temperature water vapour air humidity 30°C 50g 10g 10/50 = 20% Not yet saturated 10mins later (decreases) 20°C 30g 10g 10/30 = 33% Not yet saturated 10mins later (decreases) 10°C 10g 10g 10/10 = 100% Saturated Dew point! 10mins later (decreases) 8°C 6g 6g 10/10 = 100% Saturated! 4g of water vapour condenses into water droplets Dew point Dew point A certain degree of temperature when the air becomes saturated with water vapour, and the condensation starts. To be more specific When air temperature decreases, its capacity to hold water vapour decreases; When the air temperature decreases to a certain temperature where the air can no longer hold its current moisture content, that certain temperature is called the dew point. (Then the condensation starts).  Is the dew point fixed? Decreasing Carrying capacity of Amount of water vapour in the Relative temperature water vapour air humidity 30°C 50g 10g 10/50 = 20% Not yet saturated 20°C 30g 10g 10/30 = 33% Not yet saturated 10°C 10g 10g 10/10 = 100% Saturated Dew point! 8°C 6g 6g 10/10 = 100% Saturated! 4g of water vapour condenses into water droplets  Is the dew point fixed? (NO!) The given temperature = 20°C Amount of water Carrying capacity of water Relative Dew point vapour in the air vapour humidity Group of 25g 30g 25/30 = 83% ~18°C air (A) Group of 15g 30g 15/30 = 50% ~13°C air (B) Group of 5g 30g 5 /30 = 17% ~8°C air (C) The dew point changes with the amount of moisture in the air. The relationship between air pressure and weather Low Air Pressure = Unstable Weather Warm air rises with lots of lower pressing down water vapour from the Low air pressure force ground surface Air cools down (the rising air is with lots of water vapour) Increases condensation Dew point Moist, cloudy, rainy, and unstable weather conditions The relationship between air pressure and weather High Air Pressure = Stable Weather Cold air sinks from the higher pressing down high air pressure upper Troposphere force The sinking air warms up 1. Source of water vapour (Dry) 2. Air water vapour capacity Decreases condensation Stable; clear skies. Ozonosphere UV (ultraviolet radiation) Why do airplanes quickly ascend to the stratosphere after takeoff? This is because in the troposphere there are always a lot of wealther in there but after the airplane get out of the troposphere to the straosphere there will not have any wealther in that lay. Why does wealther mostly occur in the Troposphere? In the above layers (stratosphere) because the air is warmer as altitude increase, so air contains a limited amount of water vapour. The vast amount of water vapour is concentrated in the troposphere because of the gravity. Why do airplanes quickly ascend to the stratosphere after takeoff? To avoid extreme weather conditions in the Troposphere like ( Turbulence, rainstorm, typhoon) Wealther Temperature: Degree Celsiuo (°C）or Degree Fahrenheit (°F) Thrmometer Preciptation: The amount of moisture that has fallen from the sky to the Earth’s surface ( rain, snow, hail, sleet) millimetes ( mm) or centietres ( cm ) Rain gauge depth of liquid Air pressure: The weight of air on the Earth surface that creates a pressing down force. millibars (mb) 970 mb to 1040 mb Barometer Humidity: the amount of water vapour in the air percentage(%) Hygrometer amount of water vapour in the air at a given temperature Wind direction: compass directions ( North, East, West, South, Northeast, Southeast, etc.) wind vane, or a Wind sock SW to NE( Southwest) NW to SE( Northwest) Wind speed: NE to SW( Notheast) How fast the wind is blowing miles per hour (mph) or kilometers per hour ( kph) Anemometer turning the cups and a dial Cloud Cover: Oktas 0 Oktas (clear shky) to 8 Oktas( sky completely covered by clouds) Divide oit mentally by 8 Eyes PM10: The concentratupion of tiny particles(10 micrometres or less(p) in the air Optical Particle Counter SMG= Macao Stevenson Screen Thermometer Hygrometer Barometer Installing Weather Monitoring Stations Ship Hight Hills (High Altitudes) Major roads and bridges and Airport Residential and commercial areas Weather balloon Why does the temperature decrease with height in the troposphere? The greater the different in air pressure, the stronger the faster the wing. 1. Isobal 2. wider 3. small 4. air pressure 5. gentle 6. slow 7. narrower 8. greater 9. air pressure 10. strong 11. fast Pressure gradient force It is a force that drives wind from high air pressure areas to low air pressure area. LAP = unstable weather Warm air rises from the lower atmosphere. air cools down ( with lots of water vapour). Lower pressing down force. increase condenstion. LAPA unstable weather Fog A group of water droplets suspended in the lower troposphere. Radiation Fog The Global distribation of rainforests is mainly distributed along the equatorial low-air pressure belt. Q1: 1...........belt 2. High tempera 3.......rises 4. Low...pressure 5. Unstable weather 6. Increased condensation 7. Heavy rain 8. Plants ( heavy rain/high temperature 9. Con: Q2: The Coriolis force In the northern hemisphere, the wind is deflected to the right. In the southern hemisphere, the wind is deflected to the left.