Climatology and Meteorology

Climatology and Meteorology


Thermometers measure temperature.

 Some types of thermometers:

   - liquid-in glass



- bimetallic


 - infrared



Liquid in Glass Thermometer


Most common for everyday use (medicine, cooking, etc.)

Liquid is either mercury or alcohol

Difficult to automate – led to development of other thermometers

Bimetallic Thermometer

Uses a coil of two different metals attached to one another

Different metals expand at different rates

Used in:

round outdoor thermometers


Also difficult to automate

Infrared Thermometer


Measures the infrared radiation emitted by an object (night-vision uses it)

Used to take an instant (not delayed) temp reading of the air.

Easily automated

- but other aspects such as ground color can affect temp readings

Thermoelectric Thermometer


Most common thermometer for automated stations

Advantages: Rugged, reliable, wide temperature range, inexpensive, and fast response

Works by passing a known voltage through a wire who’s resistance varies as a function of temperature. 



Used to measure wind speed

Most common type = cup anemometer

When the wind is gusty, it overestimates the avg. wind speed because of momentum

Must be placed far away from obstacles to be accurate (Distance = 10x the height of tallest object)

Wind Vane


Measures wind direction

Points parallel with the wind

Has a “fatter” tail than head so it won’t point 180ยบ in the wrong direction.

Easily automated with a rotating sensor inside the joint with the pole.



Measures atmospheric pressure 

Works like a weight scale for the air above it

Aneroid barometer uses gears attached to a sealed air container that expands or contracts with decreasing or increasing pressure, respectively.

Mercury barometer has a bowl with liquid in it and a tube sealed at the top and open at the bottom immersed in the liquid.  When pressure rises, the mercury in the tube rises. 


Rain Gauge


Several kinds but tipping bucket rain gauge is the most useful since it can be automated.

How it works:

    - Rain falls into one of two buckets 

    - When it’s fills up with .01” of rain,

        gravity causes it to tip

    - Other bucket fills and tips

    - Number of tips counted electronically

Other instruments

Many other instruments are used such as a hygrometer which measures humidity.

There are other instruments to collect data that we will discuss later (radar, satellites, and rawindondes)

In METR 3613 “Meteorological Instruments” you will learn MUCH more about this subject.


Networks are used to collect mass quantities of weather data.  (most are stationary)

ASOS Network (Automated Surface Observation System) – nationwide network for measuring weather conditions every hr.

Oklahoma Mesonet – unique to Oklahoma, dense network of weather stations in entire state, measuring conditions every 15 min.


View of a Typical Mesonet Station