Wind and Air Pressure Notes

Slides:



Advertisements
Similar presentations
What we now know: Difference between weather and climate.
Advertisements

Weather.
Global Wind Patterns and Weather & Weather Basic
12.2 Weather Systems Coriolis effect The Coriolis effect, which is a result of Earth’s rotation, causes moving particles such as air to be deflected.
Fronts Weather Systems
Weather and Climate. Meteorology The study of the atmosphere The study of the atmosphere –Rain, dust, haze, smoke, lightening-- the weather.
Meteorology 12.1 The Causes of Weather.
Air masses and Fronts.
Weather Systems SWBAT describe how the rotation of Earth affects the movement of air; compare and contrast wind systems; identify the various types of.
Objectives Vocabulary
Guided Notes for Weather Systems
* The relative measure of the amount of water vapor in the air * Psychrometer – measures the humidity * Water vapor affects the density of the air. * Cold.
[ORIGIN from Greek anemos ‘wind’][ORIGIN from Greek baros ‘weight’]
Introduction to Meteorology UNIT 10 STANDARDS: NCES 2.5.1, 2.5.2, 2.5.3, 2.5.4, 2.5.5, LESSON 1.
Air Masses and Fronts. An air mass is a large volume of air in the troposphere with similar characteristics of temperature, pressure and moisture as the.
Meteorology Regents Earth Science St. Martin de Porres School Mrs. Canfield.
The Causes of Weather Meteorology is the study of atmospheric phenomena. The Causes of Weather.
8 th Weather Student Part 2. Cloud Cover Symbols You will often see the circles drawn on a weather map MENU.
What is an Air Mass?  Air masses are large bodies of air which have similar temperature and moisture characteristics.  Air masses form when air stays.
Wind Atmospheric Circulation (22:39min). Wind The horizontal movement of air from an area of high pressure to an area of lower pressure. Caused by the.
AIR MASSES AND FRONTS By: Ms. Nail.
Whooosh!!!!! When you open the valve on a bicycle tube, the air rushes out. Why? The air inside the tube is at a higher pressure than the air outside the.
Dynamics in Earth’s Atmosphere
Climatic Interactions
Section 1.2 The Causes of Weather
Air Masses and Fronts.
Global and Local Winds.
12.2 Weather Systems.
Weather Patterns and Maps
Sit somewhere Pick up a weather sheet and complete.
Dynamics in Earth’s Atmosphere
What direction do high and low pressure systems spin
Section 12.2 – Weather Systems
REMINDER – QUIZ CH.11 WEDNESDAY
Weather Systems Essential Questions
Air Masses and Fronts REVIEW
Under Pressure As we know, the air in the atmosphere is made up of a number of gases. These gases press down on the Earth’s surface, exerting a force.
Weather Systems.
Section 2: Weather Systems
Air Masses, Fronts.
24-1 Air Masses.
Warm-up What is weather?.
Dynamics in Earth’s Atmosphere
Chapter 12 The Causes of Weather.
Airflow of cyclones & anticyclones
Local Winds.
12.2 Weather Systems.
Objectives Compare and contrast the three major wind systems.
Journal #46 What do the following symbols mean? c m P T
Just how does it work? Atmospheric pressure= 14.7 psi
Weather Vs Climate Activity
Section 2: Weather Systems
Air Masses and Fronts.
Global Winds.
Air Masses Chapter 21 Section 1.
North American Air masses
Weather Forecasting.
Air Masses, Fronts.
Air Masses and Fronts.
Winds.
Just how does it work? Atmospheric pressure= 14.7 psi
Latitude What is Latitude? Lines of Latitude run horizontally
Bellringer A bunch of cloud droplets join together. What is this called? Coalescence Quiz FRIDAY, will cover
Wind and the Coriolis Effect
Air Masses and Fronts Page 21 Air mass
Air Masses and Fronts.
Winds Wind is caused by differences in air pressure.
Weather Systems 12.2.
Air Pressure and Winds Earth Science Ch. 19.
Winds- Now with even better explanations!
Presentation transcript:

Wind and Air Pressure Notes Wind is named for the direction its COMING FROM, NOT the direction its going to. Therefore, a northeast wind means its coming from the northeast and moving towards the southwest. Example: Wind speed = 12 mph, Wind direction = SE This means the wind is moving at 12 mph FROM the southeast.

Wind and Air Pressure When a high pressure system develops, air moves outward from the high pressure area and clockwise. When a low pressure system develops air moves inward to the low pressure area and counterclockwise.

H L

Wind and Air Pressure Air pressure is measured using a barometer. The units are either millibars (metric) or inches of mercury (English). Lines that connect equal air pressure on a weather map are called isobars. The closer the isobars are to each other, the higher the wind speed.

ESRT – page 13 has a pressure conversion chart which will be helpful. 996.0 millibars 29.41 inches

Not so windy!! Windy!!

Air Masses An air mass is a large body of air that takes on the characteristics of the area over which it formed. There are 2 main ways to classify air masses: 1. Those that form over land are dry. We call these continental (c) air masses. 2. Those that form over water are moist. We call these maritime (m) air masses.

ESRT– bottom of page 13 gives you the names and symbols of these air masses for free!

Air Masses 1. Tropical (T) = warm 2. Polar (P) = cold Once it is determined if it’s a continental air mass or a maritime air mass, there are 3 different temperature classifications: 1. Tropical (T) = warm 2. Polar (P) = cold 3. Arctic (A) = VERY cold

cT = continental tropical (dry and warm) Now, we can combine the “c” or “m” from the type of air mass and the “T”, “P”, or “A” from the temperature to create each type of air mass: cT = continental tropical (dry and warm) cP = continental polar (dry and cold) mT = maritime tropical (moist and warm) mP = maritime polar (moist and cold) cA = continental arctic (dry and very cold) Not commonly used outside of ESRegents There is no such thing as a mA air mass – it would be so cold that the moisture would be frozen.

ESRT– bottom of page 13 gives you the names and symbols of these air masses for free!

Global Winds There are three basic wind zones on Earth. 1. The trade winds 2. The prevailing westerlies 3. The prevailing easterlies

Global Winds The trade winds are found at 30º N and 30º S latitude. At these 2 places, air sinks, warms up and then moves towards the equator where it rises again. This process is a convection current!!

Page 14 of ESRT

L The sinking air from the north and south hemispheres converge at the equator and are forced upward. This creates a low pressure at the equator.

Global Winds The prevailing westerlies flow between 30º and 60º north and south latitude. We are located in this zone!

Remember, wind is named for the direction it comes from Remember, wind is named for the direction it comes from. So, these winds are actually blowing towards the east. **This is why weather moves from west to east in the United States!! These winds move towards the poles.

Page 14 of ESRT N This is us W E S

Global Winds The prevailing easterlies (a.k.a. polar easterlies) are found between 60º north and south latitude and the north or south poles. They are characterized by very cold air.

Global Atmospheric Circulation Model

ESRT– bottom of page 14 has a planetary wind belt diagram Global Winds ESRT– bottom of page 14 has a planetary wind belt diagram

The Coriolis Effect Because the Earth rotates from west to east all winds in the northern hemisphere blow opposite the direction than the ones in the southern hemisphere. In addition, because it rotates, all winds on Earth are slightly bent or curved rather than straight. This is called the Coriolis Effect. Winds curve to the right in the northern hemisphere and to the left in the southern hemisphere.

Coriolis Cannon Game!! Rolling a ball on a Merry go Round

Coriolis Force

The Jet Stream The jet stream is literally a river of wind high in the atmosphere. The jet streams can steer major air masses, pressure systems, and fronts in certain directions. There are two main jet streams in each hemisphere. A subtropical jet stream and a polar jet stream.

Coriolis Force

Fronts Sometimes air masses can collide with each other. This will form a front. A front is a narrow region separating two air masses of different densities. There are four types of fronts: 1. Cold front 2. Warm front 3. Stationary front 4. Occluded front

Fronts Cold Fronts: In a cold front ,cold dense air will displace (warm air and force the warm air upwards. Type of weather associated with this type of front is clouds, rain, and thunderstorms. The symbol on a weather map is a blue line with blue triangles that point in the direction of the cold air movement.

Warmer Colder Warm Cold

Cold Front and Warm Fronts

Fronts Warm Fronts: In a warm front, warm air advances and displaces cold air. Since cold air is more dense, so it stays on the bottom and the warm air rides over the top of it and condenses into water vapor. Weather associated with a warm front is usually a lot of clouds and rain. The symbol on a weather map is a red line with red semicircles pointing in the direction the warm air advances.

Colder Warmer

Cold Front and Warm Fronts

Fronts Stationary Front: Sometimes, when two air masses meet, neither one advances. They both stay stationary. It’s kind of like a battle between the two air masses! You may get rain and clouds with this type of front, but not always. Symbol on a weather map is a cold front symbol on one side and a warm front symbol on the other side.

Warmer Colder

Fronts Occluded Front: Some cold air masses move so fast that they overtake a warm front. Warm air will get wedged upward. There are now 2 cold air masses. The original one associated with the warm front and the new one that overtook the warm front.

Fronts Since warm air is squeezed upward, clouds and rain is very common on both sides of the occluded front. Occluded fronts are associated with low pressure systems. Symbol is alternating triangles and semicircles. It almost looks like a zipper. The cold front symbol moves in on the warm front symbol and zips together to create and occluded front.

Fronts ESRT– bottom of page 13 gives you the front symbols with their names.