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The purpose

Boulder Environmnetal Sciences and Technology develops and fabricates microwave radiometers, passive microwave sensors for environmental observations.

Space-based microwave radiometers are the most impactful sensors (see, e.g., Recent progress in all‑sky radiance assimilation, Alan Geer, et al., 2019) for weather forecast errors reduction and climate observations (e.g., Impact of satellite data, English, S.J., et al., 2013).

Our goal is to make meteorological observations more prevalent, informative, consistent, precise, and accurate.  We believe developments in radiometry will have a tremendous impact on the way scientific data is taken.

Clear air atmospheric absorption within the microwave spectrum from 2 to 1,000 GHz

How does it work?


The microwave spectrum covers a large range of wavelengths, from about 0.3 mm at 1,000 GHz to about 30 cm at 1 GHz. This wavelength range is capable of providing important measurements, such as snow cover, soil moisture, sea ice, rain rate, snowflakes, hail, atmospheric humidity and temperature, profiles, and more. The most important observations of the Earth water and energy cycles are done by microwave radiometers.

One of the most important assessments of the atmosphere is water content. Water drives weather events. Practically any form of water provides a significant signal within the microwave spectrum. Because of this, microwave radiometry can obtain very useful information regarding clouds, surfaces under the clouds, and the status of the atmosphere. In addition to measurement of the total atmospheric column of water (gas), radiometers also can evaluate cloud liquid water equivalent. Moreover, radiometer are the most effective sensor for detection of cloud particle phase, i.e., whether a cloud is composed from ice, liquid, or a mixure of the two. That is very useful for detecting supercooled liquid in the atmosphere, which is very dangerous for aviation.

Longer wavelengths can penetrate clouds, fog, and smoke, providing unique observations of things concealed by a cloudy sky.

A ground-based radiometer pointed upward can “see” the complete atmosphere, all the way up to background cosmic microwave radiation, allowing it to “see” the Big Bang.

Other names used for radiometry:

     – Passive microwave remote sensors

     – Microwave radiometers

     – Radiometers

     – Millimeter wave radiometers

     – Microwave temperature and humidity profilers​​