science 1206 weather notes

Dec 6­1:17 PM

Unit 2: Weather

Weather Lore:

• ways to keep track of common trends in weather patterns

• some have scientific facts, while others are more about coincidence

• weather lore may vary from place to place as different locations have different weather patterns

• weather lore is also tied into climate

> climate: average atmospheric conditions over time

> weather: conditions of the atmosphere at the current time

What is today's weather? What is the local fall climate?

science 1206 weather notes

Dec 6­12:43 PM

• “A fine Christmas, A fat churchyard”

• “April showers bring forth May flowers”

• “March came in like a lamb and goes out like a lion”

• “If Candlemas Day be fair and fine Half the Winter is left behind”

science 1206 weather notes

Dec 6­1:15 PM

• “If the wind’s in the east on Candlemas Day, There it will stick till the first of May”

• “Winter thunder means summer’s hunger”

• “A year of snow, a year of plenty”

• “A peck of March dust is worth a king’s ransom”

science 1206 weather notes

Dec 6­1:15 PM

• “When the winds of October won’t make the leaves go; then a frosty Winter and banks of snow”

• “A warm Christmas, a cold Easter”

• “Evening red and morning grey; double signs of one fine day”

• “A red sun got water in his eye”

science 1206 weather notes

Dec 6­1:15 PM

• “The moon with a circle got water in her beak”

• “Clear moon, frost soon”

• “When the rain comes from the south, it blows the bait into the fishes mouth”

• “When the wind veers against the sun, trust it not, for back ‘twill run”

science 1206 weather notes

Dec 6­1:15 PM

• “Rain before seven, Lift before eleven”

• “After a storm come a calm”

• “Quick thaw, long frost”

• “If the goats come home in file, get your fish in covered piles”

And more!

science 1206 weather notes

Nov 22­10:30 PM

• based mainly on measured values

• still involves some observations

Value ToolAmount of precipitation Rain gaugeKind of precipitation ObservationTemperature ThermometerWind Speed AnemometerWind Direction Weather VaneHumidity HygrometerPressure Barometer

Cloud Cover / Types Radar / Satellites / Eyes

• multiple instruments are often grouped together in weather stations or weather balloons (radiosondes)

Modern Weather Prediction

science 1206 weather notes

Nov 22­10:55 PM

• while temperature is an important part of the current conditions, humidity and wind determine how it "feels" outside

> high humidity, especially in the summer, will cause it to feel hotter (humidex)

> high winds, especially in the winter, will cause it to feel colder (wind chill)

> note that the "humidity" in most forecasts is actually the relative humidity

• a change in pressure can indicate a change in weather> decreases in pressure can indicate a storm approaching> increases in pressure often indicate clearing

https://crosswordlabs.com/view/weather­terms23

science 1206 weather notes

Nov 23­11:21 AM

Weather Maps

science 1206 weather notes

Nov 27­11:55 AM

Extreme low pressure (cyclone)

High pressure system (clear sky)

science 1206 weather notes

Nov 23­11:38 AM

science 1206 weather notes

Nov 23­11:40 AM

science 1206 weather notes

Nov 22­11:23 PM

Weather Dynamics

• changing weather occurs because of uneven heating of Earth's surface

••equatorial regions receive more sunlight, and therefore more heat, than the poles

••regions that are tilted away from the sun receive less direct light so the heat is spread out over a larger area

••our dynamic weather is mainly due to the energy trying to balance out

••difference between albedo (reflection) values can also result in more heating differences

science 1206 weather notes

Dec 11­12:08 PM

• the sun is the primary source of energy for Earth

• we do not absorb all the energy from the sun

• heat energy can do one of three things

• pass through an object• be absorbed by an object• be reflected by an object

• albedo is a measure of reflection

• of the energy coming into Earth• 27% is reflected by clouds• 20% is absorbed by clouds• 3% reflected by surface• 50% absorbed by land and water

• the higher the reflection, the higher the albedo• clouds = high albedo• land = low albedo

List three items with high albedo and three with low albedo.High Albedo Low Albedo

Energy

science 1206 weather notes

Nov 28­1:10 PM

Heat Sinks

• as objects absorb energy they become warmer

Good Heat Sink

• tends to heat and cool slowly• can hold a lot of heat (high heat capacity)

• releases more heat as it cools

Poor Heat Sink

• tends to heat and cool fast• can't hold a lot of heat (low heat capacity)• releases little heat as it cools

• heat capacity refers to how much heat is required to raise the temperature of an object

• specific heat capacity refers to exactly how much heat is required to heat 1 g of a substance by 1º

science 1206 weather notes

Dec 1­8:42 AM

1) Why is the ocean a good heat sink?

2) Why is soil a poor heat sink?

3) Compare the daily average temperatures of St. John's, NL and Ville­Marie, QC. Why might there be such a difference?

"During the day the temperature may reach 50°C, when at night it may fall to below 0°C. Deserts have less than 250 mm of rainfall per year. The rain can be unreliable. Most deserts are found between 20° and 35° north and south of the equator."

4) Consider the difference between day and night temperatures locally. Why is the amount of change so different in Newfoundland compared to a desert?

* ST JOHN'S A NL 47°37' N 52°44' W

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Year Code

Daily Average (°C)

­4.5 ­4.9 ­2.6 1.9 6.4 10.9 15.8 16.1 12.4 7.4 3.0 ­1.5 5.0 A

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Year Code

Daily Average (°C)

­15.0 ­12.8 ­6.4 2.9 10.5 15.7 18.3 17.1 12.3 6.0 ­1.8 ­9.6 3.1

VILLE MARIE QC 60.52 47°21' N 79°26' W

science 1206 weather notes

Dec 1­9:20 AM

Energy Transfer

• Four basic forms of energy transfer involved in weather

1) Radiation

• transfer of energy in waves (no medium required)

• how the sun transfers energy to Earth

• important as the sun is the source of energy for Earth

2) Conduction

• transfer of energy through collision of particles

• occurs best in solids because particles are close

• occurs too slowly to have a major impact on weather

3) Convection

• vertical transfer of energy by movement of particles in fluid (liquid or gas)

• as fluid gains energy (warms) the particles spread so they become less dense and rise

• cooler fluid replaces the warm fluid that has moved

• very important to weather when combined with advection

4) Advection

• the horizontal transfer of energy by movement of particles

• essentially part of convection current

• very important to weather when combined with convection

heat source

warm air rises

air moves from high to low pressure

air moves from high to low pressure

air cools and falls

Convection Current

science 1206 weather notes

Dec 3­12:29 PM

Questions

1) Why isn't conduction considered important to weather?

2) What type of energy transfer would you consider most important? Why?

3) Describe how heat from a baseboard heater spreads through a room.

4) Usually baseboard heaters are installed near windows with the controlling thermostat on the opposite wall. Why might this be the case?

science 1206 weather notes

Dec 8­12:00 PM

Condensation ­

Evaporation ­

Runoff ­

Transpiration ­

Sublimation ­

Precipitation ­

Water Cycle

• water that is absorbed by land is part of groundwater

• groundwater will eventually find its way back into the water cycle

science 1206 weather notes

Jan 14­11:47 AM

Water Cycle Diagram

science 1206 weather notes

Dec 8­12:41 PM

Travelling Through The Water Cycle

Using at least 4 state changes write an interesting story of the history of the water coming out of a household tap.

science 1206 weather notes

Dec 4­9:09 PM

Atmosphere’s Role in Supporting and Protecting Earth:

The atmosphere acts as a shield that protects Earth in different ways:

• protection from solar radiation

• ozone protects Earth's surface from harmful ultraviolet rays

• protection from meteor impact> since the density of the atmosphere increases the closer you

come to Earth’s surface, meteors burn up due to friction as they approach Earth’s surface

• oxygen, nitrogen, and carbon dioxide are needed to support life

• regulates the water cycle, supplies Earth's surface with water

• keeps temperatures within life‐supporting range

• circulates air to maintain a fairly constant balance of energy worldwide

MOST OF THE TIME

science 1206 weather notes

Dec 9­1:23 PM

Wind

• wind is the movement of air in the atmosphere

• local winds occur in small regions (relatively)

• prevailing winds are wind patterns that affect large regions around the world

• the Corilolis Effect along with convection currents causes these prevailing winds

• the Corilolis Effect is actually fairly weak and is often exaggerated

science 1206 weather notes

Dec 9­2:10 PM

science 1206 weather notes

Dec 9­2:12 PM

science 1206 weather notes

Dec 12­12:51 PM