MIAMI - Hurricane season is here and a new forecasting tool may be put to use this season. The National Hurricane Center is working to incorporate what is called Satellite Aperture Radar (SAR), which is satellite derived wind information into their forecast systems.
Satellite imagery, visible and infrared, are used to show formation and development of tropical cyclones, but these tools have their limitations. Those images only allow forecasters to see what is above the clouds. Additional useful information can be found below the clouds, and SAR is the newest tool to help get that data. SAR is a crucial tool for real-time forecasting of powerful storms that is already in use for some forecasting agencies.
In 2020, the Joint Typhoon Warning Center (JTWC) gained access to the new remote sensing tool. SAR provides highly detailed data of wind speeds at the ocean surface by transmitting radar pulses and recording both the amplitude and phase of the reflected return signals. This allows for the creation of high-resolution 2D maps that can be used to help improve estimates of a storm’s eye location. SAR can be useful in estimating other important storm parameters that are commonly used by forecasters, such as maximum wind speeds, the radius of the maximum winds, and the distance and areal extent of the winds. From there forecasters can use this data to further characterize a storm.