socialstudiesandenglish4: UNIT 2 WEATHER AND CLIMATE

THE WEATHER IS THE ATMOSPHERIC CONDITIONS

AT A CERTAIN TIME

IN A CERTAIN PLACE

THE WEATHER CAN CHANGE: IT CAN BE

SUNNY IN THE MORNING

RAINY IN THE AFTERNOON

AND WINDY IN THE EVENING

WEATHER IS DETERMINED BY FOUR DIFFERENT FACTORS:
1. TEMPETARUTE

2. HUMIDITY

3. WIND

4. PRECIPITATION.

1. THE TEMPERATURE IS A MEASURE OF HOW HOT OR COLD AIR IS.

WE MEASURE THE TEMPERATURE WITH A THERMOMETER

THERE ARE TWO TYPES OF SCALES:
CELSIUS OR CENTIGRADE (ºC) - FREEZING IS AT 0ºC
FARENHEIT (ºF) - FREEZING IS AT 32ºF.

2. HUMIDITY DESCRIBES HOW MUCH WATER VAPOUR IS PRESENT IN THE AIR. WHEN IT IS VERY HUMID, FOG AND MIST CAN FORM.

WE MEASURE HUMIDITY WITH A HYGROMETER.

3. WIND IS MOVING AIR.

DIFFERENT TEMPERATURES CAUSE WIND. HOT AIR GOES UP AND COLD AIR GOES DOWN.

TYPES OF WIND:

BREEZE (A LIGHT WIND)

GALE (A STRONG WIND)

HURRICANE (A VERY STRONG WIND)

WE MEASURE THE DIRECTION OF THE WIND WITH A WEATHER VANE.

WE MEASURE THE SPEED OF THE WIND WITH AN ANEMOMETER.

PRECIPITATION IS THE AMOUNT OF WATER THAT FALLS FROM THE CLOUDS.

THERE ARE THREE TYPES OF PRECIPITATION:

RAIN (LIQUID WATER): WATER DROPLETS THAT MEASURE MORE THAN 0,5mm ACROSS.

SMALLER DROPLETS FORM DRIZZLE, A LIGHT RAIN.

SLEET: THE AIR IS COLLER AND FROZEN CRYSTALS CAN FORM, IT IS A MIXTURE OF RAIN AND SNOW.

HAIL (SOLID WATER): FORMS WHEN WATER DROPLETS ARE PUSHED UP BY RISING AIR CURRENTS IN THUNDERSTORMS. THEY FREEZE IN THE CLOUDS AND THEN START TO FALL AGAIN.

SNOW (SOLID WATER): THE CLOUD OS LOW AND THE AIR AROUND IT IS COLD AND DRY. THE LITTLE DROPLETS INSIDE FORM ICE CRYSTALS ADN FALL AS SNOW.

WE MEASURE THE AMOUNT OF RAINFALL WITH A PLUVIOMETER OR RAIN GAUGE

CLOUDS
CLOUDS FORM WHEN WARM AIR RISES AND THEN COOLS DOWN.

THE DIFFERENT TYPES OF CLOUDS RESULT IN DIFFERENT TYPES OF WEATHER:

CUMULUS CLOUDS: FLAT AND FLUFFY = GOOD WEATHER.

STRATUS CLOUDS: FORM IN LAYERS AND ARE LOCATED LOW IN THE SKY = DRIZZLE AND FOG.

CIRRUS CLOUDS: THINNER AND LOCATED HIGHER UP IN THE SKY = BAD WEATHER IS COMING.

PREDICTING THE WEATHER
PROFESSIONAL METEOROLOGIST PREDICT WEATHER COLLECTING INFORMATION ABOUT:
RAINFALL
TEMPERATURE
SUNSHINE
WIND SPEED
TO DO THAT, THEY USE DIFFERENT DEVICES:

1. WEATHER BALLOONS CARRY INSTRUMENTS HIGH IN THE ATMOSPHERE TO MEASURE TEMPERATURE, AIR, PRESSURE AND HUMIDITY. THEN SEND THE INFORMATION TO WEATHER STATIONS.

WEATHER STATIONS SEND REPORTS TO WEATHER FORECAST CENTRES.

WEATHER SATELLITES ORBIT THE EARTH AND TAKE INFORMATION ABOUT WEATHER.

WITH ALL THESE DATA WE CAN MAKE GRAPHS

WEATHER FORECASTS USE WEATHER MAPS WITH SYMBOLS TO SHOW VISUAL PREDICTIONS.

CLIMATE IS THE TYPICAL TEMPERATURE AND PRECIPITATION IN A PLACE OVER A LONG PERIOD OF TIME.
THERE ARE THREE MAIN CLIMATIC CATEGORIES:
POLAR CLIMATES
TROPICAL CLIMATES
TEMPERATE CLIMATES