8:55 AM | Next generation GOES-R weather satellite nearing its long anticipated launch
Paul Dorian
Overview
Weather forecasters have been waiting for this for a long, long time. The Geostationary Operational Environmental Satellite-R (GOES-R) Series is the nation’s next generation of geostationary weather satellites. There are four satellites in the series (GOES-R, GOES-S, GOES-T and GOES-U) with six primary instruments on each that will help to improve weather forecasting around the world by providing advanced imaging with faster coverage and increased spatial resolution, real-time mapping of lightning activity, and improved monitoring of solar activity. NASA is aiming to launch the $1.2 billion GOES-R satellite from Cape Canaveral, Florida on Saturday, November 19th at 5:42PM EST via an Atlas V rocket. The original launch date was set for November 4th, but delays occurred due to the threat in Florida by Hurricane Matthew.
Discussion
The US has several weather satellites in orbit, but GOES-R will be capable of taking high-resolution images of the Western Hemisphere four times better than the satellites currently in use. Instruments onboard the satellite can also take high-resolution observations of weather parameters such as wind speed, rainfall rate, snow cover and lightning. In addition to providing higher quality information for meteorologists, GOES-R will also be able to send back data at a greater rate of speed as often as once every 30 seconds which will contribute to more accurate and reliable weather forecasts and severe weather outlooks. This greater rate of speed can make a significant difference during extreme weather events such as tornado outbreaks. The ability to observe targeted areas of severe weather every 30-60 seconds will allow forecasters to see what is happening in near real-time and provide information not captured in current satellite imagery, such as the formation and evolution of rapidly-developing severe weather. Another big benefit to meteorologists by the GOES-R series of satellites will be with respect to the forecasting of tropical systems in the Atlantic Ocean. Specifically, GOES-R will provide meteorologists with better information on what is going on inside a tropical system. This advanced capability is better than relying on airplanes which can be costly and quite difficult if the tropical storm is far away from land.
In terms of lightning, the Geostationary Lightning Mapper (GLM) instrument will map total lightning (in-cloud and cloud-to-ground) continuously over the Americas and adjacent ocean regions. Research has shown that lightning flash rate increases can be a predictor of impending severe weather and total lightning data from GLM has great potential to increase lead time for severe thunderstorm storm warnings. GLM detects lightning using a high-speed camera and looks for rapid increases in light level at individual pixels compared to the slowly changing cloud scene. The GLM is sensitive to in-cloud lightning as well as cloud-to-ground lightning. This is significant as studies have indicated the total lightning activity, and the in-cloud lightning in particular, increases as storms intensify and become more likely to produce severe weather at the ground. In this way, the GLM data combined with the Advanced Baseline Imager and weather radar are expected to increase forecaster situational awareness resulting in greater warning lead-time for the public. The ground-based lightning networks detect cloud-to-ground lightning with high accuracy, but are less sensitive to the in-cloud lightning. Forecasters intend to combine the total lightning from GLM with ground-based lightning data to build a complete overall description of the lightning activity.
Not only will the next-generation satellite help out with the prediction of weather on Earth, but it will also help with weather in space as two instruments will be facing the sun. First, an instrument designed and built by CU-Boulder’s Laboratory for Atmospheric and Space Physics (LASP) known as the Extreme Ultraviolet and X-ray Irradiance Sensors (EXIS) is the first of four identical packages that will fly on the four NOAA weather satellites in the coming decade. EXIS will measure energy output from the sun that can affect satellite operations, telecommunications, GPS navigation and power grids on Earth as part of the GOES-R satellite series. Solar storms are also responsible for producing spectacular aurora near the Earth's poles. Second, the Solar Ultraviolet Imager (SUVI) is a telescope that observes the Sun in the extreme ultraviolet (EUV) wavelength range. SUVI will observe and characterize complex, active regions of the Sun, solar flares and the eruptions of solar filaments that may give rise to coronal mass ejections. "Space weather observations from GOES-R will complement those from NOAA's DSCOVR mission, providing a comprehensive look at incoming solar storms," a NOAA spokesperson said.
GOES-R is just the first step in producing more accurate weather forecasts. In 2018, another weather satellite with similar capabilities called GOES-S will be launched providing even more information about weather across the Western Hemisphere. The GOES-R series will maintain the two-satellite system implemented by the current GOES satellites flying at more than 22,000 miles above the equator matching the speed of the Earth’s rotation. The GOES system currently consists of GOES-13 operating as GOES-East in the eastern part of the constellation and GOES-15, operating as GOES-West. The locations of the operational GOES-R series satellites will be 75⁰ W and 137⁰ W. The latter is a shift from current GOES at 135⁰ W in order to eliminate conflicts with other satellite systems. The GOES-R series program is a collaborative effort between NOAA and NASA that will extend the availability of the operational GOES satellite system through 2036. GOES-R, which will be known as GOES-16 once it reaches geostationary orbit, will transition into operations immediately following an extended checkout and validation phase of approximately one year.
Meteorologist Paul Dorian
Vencore, Inc.
vencoreweather.com