1. Section 12.3 Gathering Weather Data

2. Data from Earth’s Surface
Section 12.3
Gathering Weather Data
Data from Earth’s Surface
A thermometer measures temperature.
A barometer measures air pressure.

3. Data from Earth’s Surface
Section 12.3
Gathering Weather Data
Data from Earth’s Surface
An anemometer measures wind speed.
A hygrometer measures relative humidity.

4. Data from the Upper Atmosphere
Section 12.3
Gathering Weather Data
Data from the Upper Atmosphere
Radiosonde - instrument used for gathering upper-atmosphere data.
A radiosonde’s sensors measure the air’s temperature, pressure, and humidity.

5. Weather Observation Systems
Section 12.3
Gathering Weather Data
Weather Observation Systems
Weather radar
A weather radar system detects specific locations of precipitation.
The Doppler effect is the change in pitch or frequency that occurs due to the relative motion of a wave, as it comes toward or goes away from an observer.

6. Section 12.3
Gathering Weather Data
Weather radar
Analysis of Doppler radar data can be used to determine the speed and direction at which precipitation moves.

7. Section 12.3
Gathering Weather Data
Weather satellites
Some weather satellites use infrared imagery to measure thermal energy at night to map cloud cover or surface temperature.
Some satellites use cameras that require visible light to photograph Earth and its clouds

8. Section 12.3
Gathering Weather Data
Weather satellites
A 3rd type of satellite imagery is called water-vapor imagery that shows moisture in the atmosphere, not just clouds.

9. Section 12.4 Weather Analysis and Prediction

10. Surface Weather Analysis
Section 12.4
Weather Analysis and Prediction
Surface Weather Analysis
Station models
A station model is a record of weather data for a particular site at a particular time.

11. Section 12.4
Weather Analysis and Prediction
Meteorological symbols are used to represent weather data in a station model.

12. Plotting station model data
Section 12.4
Weather Analysis and Prediction
Plotting station model data
To plot data nationwide and globally, meteorologists use lines that connect points of equal or constant values.

13. Plotting station model data
Section 12.4
Weather Analysis and Prediction
Plotting station model data
Isobars - lines of equal pressure
Isotherms - lines of equal temperature

14. Interpreting station model data
Section 12.4
Weather Analysis and Prediction
Interpreting station model data
The weather map shows isobars and air pressure data

15. Interpreting station model data
Section 12.4
Weather Analysis and Prediction
Interpreting station model data
Using isobars, isotherms, and station model data, meteorologists can analyze current weather conditions for a particular location.

16. Types of Forecasts Digital forecasts
Section 12.4
Weather Analysis and Prediction
Types of Forecasts
Digital forecasts
Digital forecast - created by applying physical principles and mathematics to atmospheric variables to make a prediction.

17. Section 12.4
Weather Analysis and Prediction
Analog forecasts
Analog forecast - comparison of current weather patterns to similar weather patterns from the past.

18. Section 12.4
Weather Analysis and Prediction
Short-Term Forecasts
Short-Term - most accurate and detailed forecasts because weather systems change directions, speeds, and intensities over time.
Long-Term Forecasts
Long-Term are less reliable than short-term forecasts.