Atmosphere Review, Cloud Types, & Form of Precipitation
ATMOSPHERE REVIEW
• The Earth’s atmosphere is vulnerable & is a thin shell compared to the size of the en6re Earth •
The layers of the atmosphere from ground up are:
• • • • • •
Troposphere Stratosphere Mesosphere Thermosphere (ionosphere) Exosphere Magnetosphere
Atmospheric Graphs
REVIEW • High-‐pressure system: air that descends because its cool • It spreads outward as it nears the ground • Brings fair weather • Low-‐pressure system: Warm air rises & draws air inward toward the center of low pressure • Rising air expands & cools • It brings clouds and precipita6on
RECALL: WEATHER - CLIMATE • Weather refers to the local proper6es of the troposphere, such as temp., pressure, humidity, cloudiness, & wind over a rela6vely short 6me period • Climate refers to the paGern of atmospheric condi6ons found across large geographic regions over long periods of @me jeopardylabs.com/play/atmosphere331. hGps://jeopardylabs.com/play/ atmosphere331
REVIEW (IN NOTES) 1. What creates wind? • Wind is created due to the uneven hea6ng of Earth’s surface & movement of air • Warmer air rises, condenses, cools, & sinks • Air travels from areas of high pressure to areas of low pressure
REVIEW (IN NOTES)
2. A person who studies weather is referred to as a what?
• A meteorologist • The word “meteor” comes from the Greek "meteoron" which meant "something in the sky” • Meteorologists study many phenomena that include the word meteor likes hydrometeors (water in the air); lithometeors (suspended soil in the air); electrometeors (electrical discharges aka lightning)
REVIEW (IN NOTES)
3. What is the defini@on for pressure? • Air pressure is the force applied on you by the weight of air molecules
4. What tool is used to measure pressure? • Barometer
REVIEW (IN NOTES) 5. High al@tudes experience _low __ pressure 6. Due to Earth’s rota@on, wind in the Northern Hemisphere rotates _to __________ the right & wind in the Southern Hemisphere rotates ________________ to the left 7. What type of weather is associated with high pressure?
• There are cooler temperatures & sunny skies (fair weather)
REVIEW (IN NOTES)
8. What type of weather is associated with low pressure? • Thunderstorms and rainy weather – warmer temperatures
9. Warm air is _LESS _____ dense and tends to RISE in the atmosphere _____
MORE dense and tends 10. Cold air is _______ SINK in the atmosphere to _______
REVIEW (IN NOTES)
11. What is the source of heat for the Earth? SUN
12. Which region gets the most direct rays? EQUAT OR 13. Which region does not get direct sunlight? THE POLES
ABSORB sunlight, 14. Dark colors __________ while light colors reflect them.
Weather and Climate
• Both weather (short-‐term) & climate (long-‐term) are the result of the interac@on of several Earth systems: 1. The movement of moisture in the water cycle that evaporates ocean water into the air where it condenses into travelling clouds/storms causing rain/snow 2. The movement of heat that begins at the sun-‐ soaked equator & moves warm air toward the poles 3. The movement of the oceans that takes icy-‐cold water from the poles to the tropics, warming or cooling the air above the water hGp://pmm.nasa.gov/educa6on/weather-‐climate
RELAT IVE HUMIDITY
• Rela@ve humidity is the amount of water vapor in the air compared with the poten&al amount at the air's current temperature • Expressed as a percentage • Depends on air temp., air pressure, & water availability • The Earth has about 326 million cubic miles of water • Only about 3,100 cubic miles of this water is in the air as water vapor > clouds > precipita6on
ABSOLUTE HUMIDITY
• Absolute humidity is a measure of the actual amount of water vapor in a par6cular sample of air • Absolute humidity is the quan6ty of water vapor in a given volume of air, expressed by weight
• Humidity indicates the likelihood of fog, precipita6on, or dew
WHAT ARE CLOUDS?
• A cloud is a large collec6on of very 6ny droplets of water or ice crystals • The droplets are so small & light that they can float in the air • The characteris6cs of clouds are dictated by many factors: the amount of water vapor, the temperatures at that height, the wind, & the interplay of other air masses
CLOUD COVERAGE
• Moisture in the atmosphere forms clouds which cover an average of 40% of the Earth at any given 6me • A cloudless Earth would absorb nearly 20% more heat from the sun
• Clouds cool the planet by reflec@ng sunlight back into space • This is known as Albedo
“ALBEDO”
• Albedo is the frac6on of solar energy (shortwave radia6on) reflected from the Earth back into space
• It is a measure of the reflec@vity of the earth's surface
“ALBEDO” • Ice, esp. with snow on top of it, has a high albedo: most sunlight hi^ng the surface bounces back towards space • Water is much more absorbent & less reflec6ve • So, if there is a lot of water, > solar radia6on is absorbed by the ocean than when ice dominates
“ALBEDO”
CLOUD TYPES Cloud Group
Cloud Height
Cirrus High Clouds = Above 18,000 a. Cirrostratus Cirrus Cirrocumulus Altostratus Middle Clouds 6,500 a. to Altocumulus = Alto 18,000 a. Stratus Low Clouds = Up to 6,500 a. Stratocumulus Stratus Nimbostratus
Cloud Type
CLOUDS
• Cirrus clouds are the most common of the high clouds; predict fair to pleasant weather – (whispy, thin, high up) • Altostratus clouds are gray, mid level clouds composed of ice crystals & water droplets (may indicate rain, snow, or storms)
• Cumulus clouds are white, puffy clouds oaen called "fair-‐weather clouds”
CLOUDS
#1.
#2.
Cirrus clouds
#3.
Altoculumus clouds
Cumulus clouds
CLOUDS
CLOUDS
CLOUD COVERAGE
• Clouds reduce the amount of heat that radiates into space by absorbing the heat radia6ng from the surface & reradia@ng some of it back down • The process traps heat like a blanket
PRECIPITAIT ON
• Air containing water vapor cools in atmosphere & therefore condenses to form droplets of liquid water • There are many different types of precipita6on: rain, snow, hail, & sleet
• They all come from clouds • They’re all forms of water that fall from the sky • They all affect life on Earth
PRECIPITAIT ON – rain
• Rain
• Drops of liquid water fall from the clouds when water vapor condenses around dust p ar6cles i n t he c louds.. • Forming 6ny droplets that eventually get too big for the cloud t o h old s o t hey f all... • Growing larger as they collect more water on their way down
PRECIPITAIT ON – snow
• Snow • Snow is ice that falls from the sky • Each snowflake is a delicately complex arrangement of ice crystals • A snowflake forms when water vapor sublimates, or turns directly from a gas into its solid form, ice
PRECIPITAIT ON – hail
• Hail • Hail is ice that falls from the sky, oaen in round shapes • Hailstones form within thunderstorm clouds when upward moving air keeps pellets of frozen water from falling • The pellets grow larger as drops of very cold water hit them and freeze • Eventually the balls of ice become so large & heavy that they fall to the ground as hailstones
PRECIPITAIT ON – hail
PRECIPITAIT ON – sleet
• Sleet • Sleet is like slush falling from the sky • Sleet forms when raindrops freeze into ice as they fall to the ground • They are usually smaller & weGer than hailstones
hGp://www.eo.ucar.edu/basics/wx_2_b.html
Exit Ticket: Weather & Fronts
1. Draw & color the symbol for a cold front & a warm front 2. Explain the movement of air in a high pressure system 3. What type of weather is associated with a low pressure system? 4. Which clouds are whispy, thin, & high up? 5. List the 4 main layers of the atmosphere star6ng @ the ground & going up 6. What surface has a high albedo? 7. What tool is used to measure air pressure? 8. A person who studies the weather is a....