1. After School Review Commack High School
Meteorology & Climate
After School Review
Commack High School

2. Ozone layer is in the stratosphere
The Atmosphere
Page 14 ESRT’s
Thermosphere
Mesosphere
Ozone layer is in the stratosphere
Stratosphere
Troposphere
Troposphere
K. Corbisiero 2010

3. Weather:
Atmospheric conditions at a specific location for a short period of time (days)
NOTE: this differs from climate because climate is the conditions over a large area over a long period of time (years)
K. Corbisiero 2010

4. Weather Variables and Instruments
Temperature
Pressure
Wind Speed
Precipitation
Humidity, Dew Point
How much the air is pushing down
(also called barometric pressure)
How fast the wind is moving
(faster when isobars are closest)
Rain, hail, sleet, or snow falling to the ground
How warm or cool the air is
Amount of moisture in the air
(water vapor)
Psychrometer
Thermometer
Barometer
Anemometer
Rain Gauge
K. Corbisiero 2010

5. Winds blow from high to low!
Land & Sea Breezes
Has to do with specific heat. Water has highest specific heat so takes longer to heat up and longer to cool down. Land heats and cools quickly. L H
Blows from land to sea
LAND BREEZE
Remember:
warm rising air is low pressure and cooler sinking air is high pressure.
Winds blow from high to low! L H
Blows from sea to land
SEA BREEZE
K. Corbisiero 2010

6. Dew Point & Relative Humidity – page 12 ESRT’s
Dew Point – the point at which condensation occurs. The air is full, and when the temperature lowers to the dew point, the moisture is forced to leave the air and condense into a liquid.
Humidity – how much moisture is in the air. 100% relative humidity mean that the air is full, no more moisture can ‘fit’ in. 0% humidity means the air is very dry.
K. Corbisiero 2010

7. Wet Bulb & Dry Bulb
The wet bulb temperature is usually cooler than the dry bulb temperature.
The closer they are, the more moisture there is in the air (the more humid it is)
K. Corbisiero 2010

8. 2°C 33 % Dew Point = ___________ Relative Humidity = ___________
Using the charts: (ESRT’s page 12)
X axis = (dry bulb – the wet bulb) = the difference between them.
Y axis = the dry bulb (dry bulb is normal air temperature)
2°C
33 %
Determine the dewpoint and relative humidity for the readings on the sling psychrometer to the left:
Dew Point = ___________ Relative Humidity = ___________
#1 Mistake Students Make – They use the wrong chart!
K. Corbisiero 2010

9. High and Low Pressure Systems
Clear (no clouds)
Dry air
Cooler air
Righty Tighty CW
Wind blows out
Sinking air mass
Cloudy
Moist humid air
Warmer air
Lefty Loosey CCW
Wind blows in
Rising air mass H L
K. Corbisiero 2010

10. Pressure Gradient Calculations – pg 1 ESRT’s Distance (use map scale)
Cloud Formation
Clouds form when warm, moist air rises and cools to a temperature below the dew point. This forces the moist air to condense. There must be condensation nuclei present (dust etc).
Pressure Gradient Calculations – pg 1 ESRT’s
Change in field value
distance
Change in air pressure
Distance (use map scale)
Gradient = =
K. Corbisiero 2010

11. Fastest wind speed because isobars are closest together
The wind is strongest between points _____ and _____ because the isobars are the __________________ together. This means there is a __________________ gradient. A
Fastest wind speed because isobars are closest together B
Closest
Steep
Wind blows from HIGH to LOW!
Calculate the gradient between points A & B:
1008 – 992 mb
35 miles
Change in air pressure
Distance (use map scale)
G = =
= 0.46 mb/mile
K. Corbisiero 2010

12. Temperature & Moisture Content
Air Masses:
Large body of air that gets its temperature and moisture content from the location it formed over.
Page 13 ESRT’s
Temperature & Moisture Content
Dry and very cool
Dry and cool
Dry and warm
Moist and warm
Moist and cool
Note:
A = Arctic – forms near the poles
P = Polar – forms in the north
T = Tropical – forms near the equator
c = Continental – forms over a continent
m = Maritime – forms over an ocean
K. Corbisiero 2010

13. NOTE: cA is NOT on this mapmP mP cP cT mT mT
NOTE: cA is NOT on this map
K. Corbisiero 2010

14. West Coast East Coast General Direction of Air Movement Across the US:
General Direction of Weather in NYS is
Northeast
K. Corbisiero 2010

15. cP cP mT Fronts Page 13 ESRT’s
Fronts are boundaries between two different air masses.
At frontal boundaries clouds form and precipitation occurs (rain in shaded area).
Page 13 ESRT’s cP cP mT
On the diagram to the left:
Label the cP and mT air masses.
Draw an arrow showing the direction the system is moving.
K. Corbisiero 2010

16. cP cP mT Warm (mT) Cold (cP) Cold (cP) Rain at the fronts
K. Corbisiero 2010

17. Drop the decimal and keep the last three digits.
Air Pressure Encoding
mb = 201
Drop the decimal and keep the last three digits.
Air Pressure Decoding
088 =
Put the decimal in the tenths place. Add either a 10 or a 9 to the front. It must be a pressure on the conversion chart!
See that there is no such pressure as 908.8? So you know you have to use 10.
K. Corbisiero 2010

18. Station Models
Page 13 ESRT’s
K. Corbisiero 2010

19. Temp = _______________ Dewpoint = ____________ Pressure = ____________
Cloud cover = __________
Wind Speed = __________
Wind Direction = ________
Winter (temp is low)
Temp = 87F
Dewpoint = 78F
Pressure mb
Cloud cover 25%
Wind Speed = 5 knots
Wind Direction = SW
Summer (temp is high) 87
150
996 78
Best chance of precipitation:
100% Cloud Cover
Temperature and Dewpoint are very close (30 and 29!)
Low pressure!
30°F
29°F
999.6 mb
100%
20 knots NE
BONUS: Which station is summer and which is winter?
Which one has the best chance of precipitation
(give three reasons why!)
K. Corbisiero 2010

20. Long term weather conditions over a large area (year to year)
Climate
Long term weather conditions over a large area (year to year)
Weather
Short term conditions over a small area and a short time (day to day)
K. Corbisiero 2010

21. Factors Affecting Climate
Latitude – The most important factor!
The coldest climates are located near the ______________
while the warmest climates are located near the _______________.
Poles
Equator
Warm
Cold
K. Corbisiero 2010

22. Even at the equator there is snow on the top of the mountains!
Elevation –
The height of a location above sea level. Locations with a high
elevation above sea level are __________________. This is why
you can find snow on the tops of mountains!
Cold
Even at the equator there is snow on the top of the mountains!
Cold at the tops of mountains
Equator – hot at surface
K. Corbisiero 2010

23. Rising air that expands, cools, and condenses Windward Side
Topography – Mountains –
Mountains are barriers that can block circulation.
They have the ability to modify climate patterns.
The side the wind comes from is the windward.
Rising air that expands, cools, and condenses
Windward Side
Lush vegetation
Leeward side
deserts
Rain on windward side only
K. Corbisiero 2010

24. Rainforests near equator
Planetary Wind & Moisture Belts –
When rising air is cooled by adiabatic expansion, moisture is released.
These latitudes, such as the equator, have a lot of precipitation. These
areas have very humid climates (rain forests)
At latitudes of about 20 to 30 degrees, there are sinking high pressure
systems being warmed. This is where many (not all) deserts are located.
These areas are arid (deserts)
Deserts at 30°N
Rainforests near equator
Deserts at 30°S
K. Corbisiero 2010

25. Ocean Currents –
An ocean current is a stream of water that circulates through the ocean. Air above the ocean current is affected by the temperature of the water – cooler currents cool the air while warm currents warm the air. The East coast of the USA has a warm current and the West coast has a cool current. At the same latitude, the East coast will have warmer temperatures than the West coast.
K. Corbisiero 2010

26. Nearness to Large bodies of Water (Inland vs. Coastal) –
Because of waters specific heat, it cools down slowly and heats up slowly.
This causes locations near the ocean or other bodies of water to have a more moderate (small temperature range – cooler in summer and warmer in winter) than inland (continental) locations. Continental locations will experience large seasonal temperature variations.
Note – Inland means far away from the coastline where oceans are
Coastal means next to oceans or large bodies of water like the Great Lakes
Inland location
Warmer summers
And cooler winters
(larger temp range)
Coastal location
Cooler summers
And warmer winters
(small temp range)
K. Corbisiero 2010

27. (shortwave) Radiation
Climate Change
Global Cooling
Caused by pollutants, dust, or ash in the atmosphere blocking the infrared radiation from reaching the Earth. A volcanic eruption can cause this.
Global Warming
Caused by the gases carbon dioxide and methane in the atmosphere. They absorb the infrared radiation. The are released by burning fossil fuels.
Greenhouse Effect
Incoming Infrared
(shortwave) Radiation
Shortwave infrared radiation enters the greenhouse
and is
absorbed.
Long wave heat is re-radiated and unable to escape out through the glass. It gets trapped inside so it gets really really hot!
K. Corbisiero 2010

28. Too much UV is BAD for you!
Ozone
A layer of ozone in the stratosphere that blocks the Suns ultraviolet radiation (which causes skin cancer) from reaching the surface of Earth. A hole in the layer is allowing too much UV reach Earth.
Has NOTHING to do with global warming or cooling!
Too much UV is BAD for you!
Always wear sunscreen when outdoors! Even on a cloudy day!
K. Corbisiero 2010

29. The End