Climatologia

1. Understanding Weather
Prepared by Prof. Craig A. Casillas Barreto

3. Water in the Air
∗ Weather is the condition of the
atmosphere at a certain time
and place.
∗ The Condition of the
Atmosphere is affected by the
amount of water that is in the
air.

4. The Water Cycle

5. Humidity

6. Humidity (Practice)

7. Factor that Affect Relative Humidity
∗ Amount of Water Vapor,
because it changes at a
constant temperature
and Pressure.
∗ Temperature, because
the amount of humidity
decrease if the
temperature rises and
increase as the
temperature drops.

8. Methods to Measure the Relative
Humidity
∗ A Psychrometer is a instrument that
is used to measure the relative
humidity. It consist of two
thermometer, one of which is a
wet-bulb thermometer covered
with a damp cloth. The other is a
dry-bulb thermometer. The
difference in temperature of both
thermometer indicates the amount
of water vapor in the air.
∗ The larger the difference between
the two readings, is the less water
vapor is in the air and thus lower
the humidity is.

9. Clouds
∗ A Cloud is a collection of a
small water droplets or ice
crystals suspended in the air,
which forms when the air is
cooled and condensation
occurs.
∗ Clouds are classified by form
and altitude.

10. Precipitation
∗ There are four major
forms of precipitation
like:
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∗
Rain
Snow
Sleet
Hail

11. Air Masses and Fronts
∗ Air mass is a large body of air
where temperature and
moisture content are similar
throughout.
∗ The moisture content and
temperature of an air mass are
determined by the area over
which the air mass form. These
areas are called source regions.

12. Fronts
∗ Fronts are
boundary between
air masses of
different densities
and usually
different
temperature.

13. Air Pressure and Weather
∗ Different air pressure in
different areas can affect the
weather and forms:
∗ Cyclones and Anticyclones.
∗ Cyclone is an area in the
atmosphere that has a lower
pressure than the surrounding
areas and has winds the spiral
towards the center.
∗ Anticyclone the rotation of the
air around a high-pressure
center in the direction
opposite to Earth’s rotation.

14. Severe Weather
∗ Severe Weathers is a weather that can cause property
damage and sometimes death.
∗ Examples of severe weather:
∗ Thunderstorms
∗ Tornadoes
∗ Hurricanes

15. Thunderstorms
∗ Thunderstorms are a usually brief,
heavy storm that consist of rain,
strong winds, lightning, and thunder.
∗ They can form from:
∗ Cold fronts
∗ Warm and moist air near Earth’s
surface
∗ Unstable atmosphere
∗ They produce:
∗ Lightning, thunder and Severe
thunderstorms
∗ Lightning is an electric discharge that
occurs between a positively charged
area and negatively charge area.
∗ Thunder is the sound that result from
the rapid expansion of air along the
lightning strike.

17. Tornadoes
∗ Tornadoes are destructive,
rotating column of air that has a
very high wind speeds, is visible
as a funnel-shaped cloud, and
touches the ground.

18. Hurricane
∗ Hurricanes are severe
storms that develops over
tropical oceans and whose
strong winds of more than
120 km/h spiral in toward
the intensely lo-pressure
storm center.
∗ They are also called
Cyclones in Indian Ocean
and Typhoons in the Pacific
Ocean.

21. Forecasting the Weather
Weather-Forecasting Technology
∗ Meteorologist need to measure various atmospheric
conditions, such as:
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Air Pressure
Humidity
Precipitation
Temperature
Wind Speed
Wind Direction

22. Weather-Forecasting Technology

23. Radar and Satellites
∗ Radar is used to find the
location, movement and
amount of precipitation.
∗ Doppler Radar is used to
track precipitation.
∗ Weather satellites provide
images of weather
systems.

24. Weather Maps
Weather Maps shows areas
of high and low pressure as
well as the location of
fronts.