Air Masses - MEEKS SCIENCE SITE

Air Masses - MEEKS SCIENCE SITE

Air Masses Introduction Video Weather and Climate Watch the Video and Fill In the Guided Viewing Sheet https://www.youtube.com/watch?v=XirAUvS_29I

Weather vs. Climate Weather: Physical conditions in the troposphere at any given moment (temperature, pressure, humidity, precipitation, sunshine, cloud cover and wind speed and direction.

Climate: A regions general pattern of weather over a long period WEATHER INSTRUMENTS WEATHER INSTRUMENTS Different

tools are used to measure a number of the atmospheres physical properties. Measurable properties include: Temperature Pressure Moisture content Wind speed Wind direction WEATHER INSTRUMENTS Temperature

is measured with a thermometer. Temperature is measured in degrees. Non-metric Metric Units: Fahrenheit (F)

Units: Celsius (C), Kelvin (K) Temperature measures the amount of heat an object has, or the amount of molecular movement. At absolute zero (0 K or -273.16C), molecules dont move.

THERMOMETERS WEATHER INSTRUMENTS Humidity is measured with a hygrometer. Absolute humidity tells you the mass of water per

volume of air (in g/m3) Also known as vapor pressure Relative humidity tells you how saturated the atmosphere is (as a percentage). Its

the ratio of absolute humidity to the maximum amount of water the air can hold at a given temperature The dew point tells you at what temperature the atmosphere would be saturated. HYGROMETER WEATHER INSTRUMENTS

Atmospheric pressure is measured with a barometer. Pressure units: Inches of Mercury: non-metric Pascals (Pa), bars (b): metric Most Mean commonly expressed in hectopascals (hPa) and millibars (mb)

sea level pressure = 29.92, 1013.25 mb (or hPa), 101325 Pa If pressure is rising, it usually means improving weather conditions. If pressure is falling, it usually means deteriorating weather conditions. Deteriorating = getting cloudy, rainy, stormy

BAROMETERS BAROMETERS HYGROMETER They measure the pressure of different values.

A barometer measures the atmospheric pressure of the air above you the weight of the air where you are. Hygrometer measures the water vapor content of the atmosphere where you are. ANEMOMETERS

An instrument for measuring the speed of the wind, or of any current of gas. WEATHER INSTRUMENTS Wind direction is measured with a wind vane.

Wind direction is expressed as a compass direction (north, south, east, west, or a combination of those: north-northwest, east-southeast, etc.) The wind direction is the direction that the wind is blowing from. In

other words, if you turn so that the wind is blowing in your face, the direction you are looking is the wind direction. WIND VANES WHATS THE WEATHER? What Creates Weather/Climate?

Air Masses Produce Weather/Climate Air mass a large region of air (thousands of square miles) having similar temperature, pressure, and moisture characteristics Air masses move and strongly influence the changing of the weather, making them very important to understand Formation of Air Masses Air

masses attain their characteristics from the part of earths surface over which they exist Simple Examples - air sitting over tropical ocean becomes warm and moist - air sitting over a desert will be warm and dry Formation of Air Masses Source

region an area of earth where air masses form - Source regions are very large - Source regions occur at high and low latitudes (mid-latitudes are too variable) Air Masses Air

masses are classified according to their temperature and moisture characteristics: 1) Based on moisture continental (dry) or maritime (moist) 2) Based on temperature tropical (warm), polar (cold), or arctic (very cold) Air Masses

There are 5 different types of air mass: 1) Continental arctic (A) or (cA) 2) Continental polar (cP) 3) Continental tropical (cT) 4) Maritime polar (mP)

5) Maritime tropical (mT) AIR MASSES: 5 TYPES Maritime Tropical (mT) a warm & humid air mass originating in the Gulf of Mexico,

Caribbean Sea, Atlantic near the Bahamas, or off Mexicos Pacific Coast Continental a Tropical (cT) hot & dry air mass originating in/near the deserts of the southwestern U.S. or northern Mexico, or the High Plains

AIR MASSES: 5 TYPES Maritime Polar (mP) Cool and moist air mass that originates in the northern parts of the Pacific or Atlantic Oceans Continental

Polar (cP) Cold and dry air mass that originates from the northern parts of North America (Alaska and northern Canada) Arctic Very

(A) cold and dry air mass that originates from the Arctic Ocean or eastern Russia (Siberia) Continental Polar Air Mass Continental polar air masses are dry and cold Form over high-latitude land surfaces (including ice) In winter, very little solar radiation causes net cooling of air mass

Extremely dry since cold air cannot contain much water vapor Typically clear and cloudless Very stable (resists vertical motion) Water Vapor in Cold Air Continental Polar Air: Very Stable Continental Arctic Air Masses Continental

arctic air masses are extremely dry, extremely cold versions of continental polar air masses The only difference: Continental arctic air masses are shallower than continental polar air masses

Continental Arctic vs. Continental Polar Maritime Polar Air Masses Maritime polar air masses are moist and cool Form over oceans (not ice) at high latitudes Cool and moist due to contact with cold ocean water

Generally cloudy Continental Tropical Air Masses Continental tropical air masses are dry and warm Form over low-latitude land surfaces Hot and dry due to contact with hot land surfaces with little moisture Generally cloud-free Fairly unstable due to heating from below

(but dryness inhibits cloud formation) Maritime Tropical Air Masses Maritime tropical air masses are moist and warm Form over warm ocean (tropical) waters Unstable conditions (moist warm air at surface) Generally cloudy and partly cloudy Responsible for daily showers/thunderstorms in the southeast U.S.

The Importance of Different Air Masses: The Pineapple Express The Pineapple express a weather phenomena that impacts the NW U.S. Constant flow of maritime tropical air into the NW U.S. Significant orographic (mountain-induced) rainfall High freezing (and snow) levels

Causes destructive flooding The Importance of Different Air Masses: The Pineapple Express The Importance of Different Air Masses: The Pineapple Express Summary of Air Masses Air Mass Modification

Air masses can be modified as they move into new regions with different surface characteristics Air Mass Modification Air

masses can be modified as they move into new regions with different surface characteristics Example: Continental polar air moves southward Air Mass Modification Air Mass Modification Air Mass Modification

CAUSES OF CLIMATE: TOPOGRAPHIC EFFECTS Water heats up and cools down more slowly than land. Thus, large bodies of water affect the climates of coastal areas. Temperatures in the lower atmosphere generally decrease with altitude. Thus,

mountain climates are usually cooler than those at sea level. The temperature of the atmosphere drops three degrees Fahrenheit for every 1000 feet in elevation rise. CAUSES OF CLIMATE: TOPOGRAPHIC EFFECTS Orographic

lifting leads to rain on the windward side of a mountain. The leeward side is usually dry and warm Windward Side - More precipitation

Leeward Side - Less precipitation Air CAUSES OF CLIMATE: AIR MASSES

masses affect regional climates by transporting the temperature and humidity of their source regions. Many times, air masses will modify (cool or warm, gain or lose moisture) as they

move across the continent KNOWLEDGE CHECK During the summer, which air mass do you think has the biggest impact on Georgias weather? During the winter, which air mass do you think has the biggest impact on Georgias weather?

AIR MASSES AND FRONTAL BOUNDARIES A frontregardless of its type (cold, warm, stationary, occluded)is the boundary between two different airmasses. The barbs (triangles) and pips (semi-circles) point the

direction the airmass is moving. The wind directions on either side of a front can clue you in on where the airmasses are moving from. In North America, if the winds are from the northern half of a compass, its source is most likely polar or arctic.

If the winds are from the southern half of a compass, its source is most likely tropical. AIR MASSES AND FRONTAL BOUNDARIES Temperature gradient is the biggest clue as to whether an airmass is Arctic, Polar, or Tropical.

Moisture content can clue you in on if its continental or maritime. If there is a strong moisture gradienttheres a significant difference in dew points on either side of a boundaryhints at a difference between a maritime and continental airmass.

A change in wind direction will also clue you into a frontal boundarys position. Remember that the wind direction is where the wind is blowing from, so that should tell you something about the airmass source region.

Recently Viewed Presentations

  • Harm Reduction Strategies for Substance Abuse

    Harm Reduction Strategies for Substance Abuse

    This model states that the user suffers from a disease of the brain that does not allow them to be able to control their drinking. ... rogerian, client-centered approach. Motivational Interviewing. MI approach. Reflections, open-ended questions, creating cognitive dissonance, enhancing...
  • Pushin' Geo - Kennesaw State University

    Pushin' Geo - Kennesaw State University

    As well as colors, normals, and other vertex data. Pushin' Geo to the GPU. Jeff Chastine
  • Springer Standard Template - International Publisher Science ...

    Springer Standard Template - International Publisher Science ...

    Synonyms relevant as search terms e.g. in Google. Ideally not words from the title because title words are automatically keywords. Introduction. Explain i) why the work was conducted ii) what methodology was employed iii) why you chose this particular methodology...
  • Apostasy 1 2 . . . I will

    Apostasy 1 2 . . . I will

    If that is the case, the church would be in a state of apostasy. * In this quote, Williams clearly states that the church had fallen into apostasy and that he lived in the hope of a restoration instigated by...
  • Traumatic Traumatic Brain Brain Injury: Injury: Physical, Physical,

    Traumatic Traumatic Brain Brain Injury: Injury: Physical, Physical,

    (Capuco & Freeman-Woolpert) She frequently misses appointments-avoidance, irresponsibility He says he'll do something but doesn't get around to it She talks about the same thing or asks the same question over and over-annoying perservation He invents plausible sounding answers so...
  • Flexible and Approximate Computation through State-Space ...

    Flexible and Approximate Computation through State-Space ...

    New search methods Kestrel (challenge problem) Achieved: Studied low-cost distributed algorithms for scheduling problems. ... distributed algorithms Phase-aware problem solving for good enough/sooner enough solutions What we try to do for the program Understanding computational challenges in ...
  • Effingham County High School Celebrates May 1, 2013 National ...

    Effingham County High School Celebrates May 1, 2013 National ...

    National College Decision Day 2016. May 1st is the date that many colleges in the US require that seniors who have been admitted either accept or reject their offer of admission. Here at ECHS, today is our day to celebrate...
  • Theory of Event Expressions  Tool to design motions

    Theory of Event Expressions Tool to design motions

    We will call them primitive motions. ... In contrast, the theatre performance is always slightly different and it depends on the feedback from the audience. The public may say "Actor X had a good day today". The research questions are:...