Sustainicum Collection

Consus The aim of the project is to establish a regional science-society network for sustainability innovations in Albania and Kosovo in order to strengthen the connection and collaboration of institutions in the field of higher education, research and practice.

Resource facts

  • Independent of the number of students
  • Up to 3 lecture units
  • Internet connection necessary
  • English, German

Resource Description

Instruction file

Additional attachments

Energy balance and energy flows in the environment – Influence of latent evaporation energy on ground surface temperature(Resource ID: 202)

This building block is mainly comprised of a guide to conducting the experiment listed below, accompanied by a description of the basic conditions, which must be met. The influence of latent evaporation energy on the energy balance and subsequently on the temperature of a surface area is demonstrated by the experiment described below. This experiment can be conducted outdoors or indoors.

Authors: Prof. Dr. Philipp Weihs, Prof. Dr.  Josef Eitzinger, Ing. Wolfgang Laube

Basic concept of the building block

The following experiment, which should be conducted on a homogeneous surface, demonstrates the influence of latent evaporation energy on surface area temperature. Students should understand the influence of evaporation on the energy balance and ground temperature and be able to measure and quantify this.

Description of the building block

The measurements can be taken within a time frame of two hours. By measuring the temperature of a surface area with the help of a thermal camera, spatial differences in temperatures on a surface are made visible.

Thermal pictures can be taken on a homogeneous paved surface.

Heated water with a higher temperature than the surface area is poured over a specified point. At the beginning, the thermal camera sees this wet surface as a hot point. When the water evaporates the heat is slowly drawn away from the wet surface area, leading to a decrease in temperature. This temperature decrease slowly, becoming visible in the thermal camera images. At the end of the experiment, the wet area is cooler than the dry surrounding surface area.

Both indoor and outdoor trial areas are appropriate, including areas of the BOKU trial sites in Groß-Enzersdorf and the Türkenschanze.

The building block is divided into four steps:

Step 1: Directions to conducting the experiment

Step 2: Setting-up the experiment

Step 3: Conducting experiment

Step 4: Analysing and interpreting the data

The course materials include:

  • Short instructions to the building block
  • A video (http://youtu.be/xHoiySZp-5c)
  • A theoretical explanation of the observed phenomena
  • Recommendations for implementing the building block in the course
  • Bibliography and links
Contact details for borrowing physical devices
Institut of Meteorology; Wilhelm Exner Building, 1st Floor; Peter Jordan Strasse 82, A-1190 Wien
Learning Outcomes
This building block is appropriate for all courses that are hands-on, exercise-oriented and that focus on the balance of energy and radiation, as well as heat generation. Students should be able to understand the influence of evaporation on the energy balance and ground temperature and be able to quantify and measure this.
Relevance for Sustainability
Evapotranspiration, for example with vegetation, has a cooling effect due to the withdrawl of latent heat. Evapotranspiration can counter excessive heat developments (e.g. in urban settings).
Related Teaching Resources
    Preparation Efforts
    Funded by
    Funded by the Austrian Federal Ministry of Science and Research within the framework of the call "Projekt MINT-Massenfächer" (2011/12)

    Comments Write Comment


    Philipp Weihs


    Philipp Weihs
    This teaching resource is allocated to following University:
    BOKU - University of Natural Resources and Life Sciences Vienna
    Institute of Meteorology (BOKU Vienna)


    Creative Commons

    Teaching Tools & Methods

    • Video
    • formteaching_experiment