A practical guide to accurate air temperature measurement

Mandatory equipment

  1. Temperature sensor - How accurate is enough? We'll get to that later in this article.

  2. Solar radiation shield - Why you ask? So that your sensor does not heat up in the sun like your car.

Set your goal

We all want to measure accurately...! So lets see how we can get there.  There are two ways:

  1. Buy a sensor & from Rotronic or Vaisala for hundreds or even thousands of dollars
    OR

  2. Mount your afforadable sensor where it can measure well...in a good solar radiation shield.

Your environment

A farm field, a dusty city street, near the ocean,

What is really important?

Do Benefits outweigh Sensor Cost?

STANDARD RADIATION SHIELDS

  • Low-cost multi-plate radiation shield

    • $100

    • increases error by 1°C (2°F) or more

    • protects sensor only from direct sunlight

  • Mid-range Radiation Shield like Davis 7714

    • $100

    • increases error by 0.5°C (1°F)

  • High-end multi-plate radiation shield from Vaisala

    • $300+

    • increases error by 0.3°C (0.6°F) or more

Double-Helix Technology

  • Helical MeteoShield Radiation Shield

    • $200

    • increases error by 0.1°C (0.2°F)

TEMPERATURE SENSORS

  • Thermistor like from Decagon

    • $30

    • accurate to ± 0.5°C (1°F)

  • Low-cost digital Temperature & Humidity probe from Davis

    • $50

    • accurate to ± 0.3°C (0.6°F)

  • Mid-range Temperature & Humidity probe like MeteoTemp or Rotronic

    • $250...$500

    • accurate to ± 0.2°C (0.4°F)

  • High-end Temperature & Humidity probe like from Vaisala

    • $2000+

    • accurate to ± 0.1°C (0.2°F)

 

Lets tear away the BS and get to the point!