Detailed information
A new cloud radar which has been developed over 10 years, may help climate scientists as well as meteorologists. It has been developed by researchers and engineers at the UK’s Science and Technology Facilities Council in collaboration with the Met Office.

Conventional weather monitors ‘can see the outside of the cloud and can tell what height it is,’ explains Brian Moyna, Senior Systems Engineer at the STFC. ‘Instruments, such as ceilometers, are often used for determining the height of the cloud base. However, they give limited information on what is happening above the cloud base. Our cloud radar gives detailed information on the cloud composition and can detect multiple layers of cloud up to a 16km altitude.’

Seeing ice and water
The level of detail given by the cloud radar has created a degree of excitement at the UK’s Met Office. ‘What our radar does is give an image that’s similar to a catscan,’ says Moyna. ‘We can find where the ice and water particles are’ Improved detail enables predictive modelling by forecasters and climate scientists.

‘What we are trying to do is to give meteorologists and climate scientists a really good picture of what’s happening inside the cloud,’ says Moyna. ‘You can measure the humidity of the cloud and the atmosphere directly above it. Being able to determine the amount and distribution of water, in a vertical section of the atmosphere, is extremely useful for refining atmospheric models used in predicting the weather and climate change.’ Normally such data could be gathered using probes such as a ‘radiosonde’ attached to weather balloons, ‘but these seldom give a true vertical profile, being blown horizontally by winds’ says Moyna.

Low cost
This radar is low cost, low power and very portable. In comparison preparing and using a radiosonde is time consuming. ‘Launching a radiosonde,’ says Moyna, ‘generally requires a person to prepare the balloon and launch it every few hours from a dedicated weather station, so coverage is somewhat limited.  The cloud radar can be operated anywhere with access to mains power – data is logged on the instrument and can be downloaded periodically or via the internet (if available). A network of cloud radars could, therefore, potentially provide greater coverage than is possible with radiosondes.’