NASA Builds Small, Low-cost Weather Sensors to Track Tropical Cyclones

NASA constructed two weather instruments to test the capabilities of small, low-cost sensors in replicating the work of bigger and more expensive satellites.

The space agency reports that the instruments have been successful in trial runs and are already delivering forecast information about tropical cyclones.

COWVR and TEMPEST

The two instruments are COWVR (short for Compact Ocean Wind Vector Radiometer) and TEMPEST (Temporal Experiment for Storms and Tropical Systems).

COWVR was launched to the International Space Station (ISS) in 2021 and its role is to estimate the speed and direction of wind at the surface of the ocean. Meanwhile, TEMPEST offers measurements for atmospheric water vapor.

These instruments are part of Space Test Program-Houston 8 (STP-H8), a mission funded by the US Space Force.

The US Joint Typhoon Warning Center uses imagery derived from their data to monitor the position and strength of tropical cyclones in the Pacific and Indian oceans.

Images from COWVR and TEMPEST were also used by a forecaster at the typhoon center in Pearl Harbor, Hawaii to locate Tropical Cyclone Mandous, which wreaked havoc in the Bay of Bengal, India in December 2022.

The Naval Research Laboratory (NRL) in Monterey, California, has also been collaborating with NASA to use imagery provided by COWR and TEMPEST data.

TEMPEST and COWVR track microwave radiation from Earth's surface and atmosphere. A tropical cyclone's internal structure may be seen in microwave scans, which gives them an edge over infrared or visible light data and help forecasters find the eye even when it is hidden by clouds, according to NASA.

Compact Weather Instruments

COWVR makes use of the technologies and designs for the Jason series of ocean-observing satellites from the NASA Jet Propulsion Laboratory.

COWVR uses a rotating dish but JPL engineers were able to streamline the instrument's construction to increase power efficiency without reducing its functions.

The instrument is about the size of a minifridge as it weighs around 130 pounds (60 kilograms). It needs about 47 watts to operate, which is about the same amount of power needed by a minifridge.

TEMPEST was a flying spare from NASA's TEMPEST-D mission that was launched in 2018. It has a budget of less than $2 million and is about the size of a cereal box. It weighs around 8 pounds (4 kilograms) and uses 6.5 watts of power.

The US National Hurricane Center has begun evaluating the COWVR and TEMPEST data that the Naval Research Laboratory has submitted.

The Joint Typhoon Warning Center plans to examine them more closely to determine whether COWVR's surface wind speed and direction data - rather than merely the imagery - improve tropical cyclone forecasts.

The US Navy's global numerical weather models continue to be evaluated by the Naval Research Laboratory using raw data from COWVR and TEMPEST.