Photo Johan Warden

Air humidity

How does air humidity vary? Relative air humidity tells you how much water vapour the air contains in relation to how much the air can hold at the temperature in question. Relative air humidity is often high during the winter and lower during the summer. The air can hold a lot more water during the summer compared with the winter.

Based on relative air humidity, other air humidity parameters can be calculated, for example absolute humidity and mixture ratios. The absolute air humidity is often low during the winter and high during the summer.

We measure relative air humidity outdoors at approx. 1.5 m above the ground. Air humidity outdoors is not the same as air humidity indoors.

Where are these measurements taken?

In the column on the right there are maps you can zoom in and out of which show the weather stations in operation in 2008.

The larger stations report temperature, precipitation, wind, air pressure, air humidity etc. several times per day. Automatic stations measure the temperature, precipitation, wind, gusts, air pressure, air humidity etc. every three hours.

The station network has changed over the years, so if there is no station marked in the area/place you are interested in, it is possible that we still have older data close by. The selection of station therefore takes place in consultation with our meteorologists.

How is the data compiled?

In SMHI's database, relative air humidity data is stored. Based on this information, other humidity measurements can be calculated. Examples of humidity measurements include:

  • relative humidity (%)
  • absolute humidity (g water/m3)
  • enthalpy (kJ/kg dry air)
  • specific humidity (g water/kg humidity air)
  • mixture ratio (g water/kg dry air)
  • vapour pressure (hPa)
  • wet temperature (°C)
  • dew point (°C)

The results are presented in the form of tables, maps or diagrams, according to your requirements. Data can be compiled in time series and monthly tables.

The number of observations of different air humidity intervals, in absolute figures or as a percentage, divided by the amount of months, can be ordered in a frequency table. The air humidity can be compared to the temperature in a temperature-humidity frequency table.

Responsible for this page Helen Ivars
Send e-mail to Helen Ivars
Close
Send e-mail You are about to send an e-mail to Helen Ivars.




Last updated 14 October 2009
Print
E-mail this to a friend
Close
E-mail this to a friend





*Required field

CONTACT PERSONS

Companies and private individuals contact the customer services department.

For technical information, dimensioning, planning and processed statistics contact Sofia Malmsten.

Non-commercial researchers should contact Else-Marie Wingqvist.


Customer Service, Climate data
Phone +46 (0)11-495 82 00
Send e-mail to Customer Service

Else-Marie Wingqvist, Hydrologist
Phone +46 (0)11-495 83 68
Send e-mail to Else-Marie Wingqvist