Like a Hurricane: A Remote Sensing Story

In May NOAA predicted an 85% chance of an above normal hurricane season for 2024. In essence, that meant a forecast of 17-25 storms with winds higher than 39mph. Out of these 8-13 would become hurricanes with winds above 74mph and between 4 and 7 would be a category 3-5, resulting in winds of 111mph or higher!

The season is well underway, will extend to November, and it has already delivered Alberto (a tropical storm that brought heavy rain with 4 fatalities) and Hurricane Beryl, a category 4 hurricane, that saw sustained winds of 150mph causing power outages, flooding and storm surges.

These both mark an exceptionally early and frightening start to the season. Among the drivers, unsurprisingly, are the warming of the oceans in the Atlantic and melting ice on land, leading to sea level rises that increase the risk of storms. These are linked to climate change and human activities, among which fossil fuels is a key contributor.

Here at Minesat, we see a unique example of how remote sensing is being used to its utmost potential, with a system that incorporates satellites, airborne and ground instrumentation, with techniques including GPS, geophysics and instrumentation and monitoring, all shared with specialists, professionals and the public through web-based mapping, tracking and tools (GIS). Ground, Sky and Space – it checks all the boxes and for a good cause. Let’s dig deeper to see what and how they are doing this in more detail.

Image Credits: Hurricane Beryl from Space (NASA/Matthew Dominick link), GOES-16 Info (NASA/NOAA link), Aircraft and Ships used by NOAA (NOAA)

Starting from space, NOAA works with NASA and has two key missions to keep abreast of severe weather conditions, the GOES mission and the Polar missions (POES and JPSS).

GOES is made up of R-Series satellites, orbiting 22, 236 miles above the equator and ensuring continuous coverage across the globe since 1975. They provide images of weather patterns, hurricanes and severe storms as much as every 30sec, which is key for real time decisions. Most importantly, they carry the first operational lightning mapper – fundamental as developing storms tend to show increased lightning activity - therefore it has the potential to increase lead time for severe thunderstorms and tornado warnings.

The Polar satellite missions, split into POES and JPSS, provide full global data coverage for short-term weather forecasting and long-term climate and environmental data records and short- and long-term forecasts including predictions for severe weather events respectively. JPSS provide most of the data for numerical weather forecasting in the US and critical observations during hurricanes and blizzards.

Amazingly, these provide up to 16 channels of information bringing visible imagery, infra-red and near infra-red and microwave information to scientists and users. See here for GOES and JPSS for a whole host of resources on both missions.

All this info is fed to the OSGS (Office of Satellite Ground Services) who provide it to users on the ground in their everyday work. The OSPO (Office of Satellite and Product Operations) is responsible for scheduling and data information for GEOS and PEOS and provide imagery and products from these satellites including, near-real time imagery of current or developing cyclones.

Image Credit: Observing systems used to improve data coverage, resolution and prediction (NOAA)

In the sky, the NOAA deploy aircraft such as the NOAA P-3 Orion hurricane for low altitudes complemented with the G-IV Jet for higher altitudes. Both are loaded with instrumentation including Doppler radar, DWSDs (Directional wave spectra drifters) and bathythermograph probes. These allow the measurement of pressure, humidity, temperature and wind direction and speed at sea surface, sea-level and in the atmosphere. DWSDs provide GPS location too, used to validate satellites and weather prediction models, and improve the forecasting of surface waves associated with tropical cyclones.

Amazingly, the P-3 Orion hunter aircrafts (Kermit and Miss Piggy!) fly through storms (with a crew of 5 onboard) and with sensors transmit measurements that provide more detail on intensity and structure while their the tail Doppler radar and lower fuselage radar scan the storm horizontally and vertically providing a real time richer view (think an MRI scan). More recently, the deployment of Stepped Frequency Microwave Radiometers (SFMRs) has enabled the measurement of ocean wind speed and rain rate in hurricanes and tropical storms - key indicators of deadly storm surges. With surges being a major cause of hurricane-related deaths, they can play an important role in mitigating this risk.

In addition, the P-3 can also release drones (UAS, unmanned aircraft systems) that can stay up for hours at a time collecting wind speed, humidity, temperature and atmospheric pressure data in the boundary layer. This boundary layer is the region that influences the exchange of heat, moisture and energy between the ocean and atmosphere and as a result understanding the conditions here help support improved modelling of hurricane intensity and behaviour.

Climbing up to a cruising altitude of 45,000 above and around the storm, we find the G-IV Jet, keeping a track on developing hurricanes in the upper atmosphere to complement the lower altitude data form the P-3. Aside from the usual Doppler radar, these are loaded with dropwindsondes (parachuted instruments dropped from aircraft with GPS and sensors for temperature, wind, pressure and humidity – up to 20-40 along the flight track) to enable forecasters to map the steering currents that influence the movement of hurricanes.

2024 has seen another advance in technology – streamsondes. The latest addition to NOAAs hurricane kit, these ultra lightweight and biodegradable (sustainability!) instruments are dropped from the P3 to gather similar data to GPS dropwindsondes. These though, are significantly smaller allowing scientists to deploy multiple drops increasing temporal and data resolution and enhancing the picture of what is going on.

Image Credits: Saildrone, Gulfstream Jet (G-IV), Drone (Unmanned Aircraft Systems), (NOAA)

Coming down to the Ground, NOAA uses Gliders, Floats and Saildrones. Gliders are autonomous underwater vehicles (AUVs) that can dive up to 1000 meters to gather data around temperature and salinity and refine hurricane forecast models. These are complemented with Argo Floats, that measure the same conditions yet at up to 2000 metres, providing another layer of resolution to build a richer picture of hurricane formation and development.

In the past decade, this has been further enhanced with uncrewed, wind/solar powered and remotely piloted drones (sailboats) provided by SailDrone. Able to handle hurricane force conditions, these provide real-time, in-situ monitoring data crucial for predicting these storms and more importantly intensity changes above the 35 mph over the 24h period. With storm intensification a cause of extensive damage and loss of life, this technology is helping NOAA to address this very real challenge.

The SailDrone is also a pivotal player in the whole value chain – aside from making multiple concurrent measurements of wind speed, wave height, temperature, pressure and salinity it can integrate observations from gliders and aircraft. This makes it possible to measure the difference between atmosphere/upper ocean and inside/outside the hurricane and transmit this data back in real time, allowing scientists to have a full as picture as possible (from satellite, to airborne to ground and validate back again) that supports better prediction of hurricane paths and intensities and improved forecast modelling. Pretty neat. See here for a great graphic of how it all works together.

Yet how is all this data made accessible and usable to those that are impacted and those that need to make decisions?

Well for the public, government and professionals:

-       the National Environmental Satellite, Data and Information Service (NESDIS) provides a GIS based web map for anyone to see live hurricane cones of activity

-       the National Hurricane Centre provide more specific information on live storms/hurricanes wind speed, severity and even arrival time forecasts

-       key Regional Specialized Meteorology Centers (RSMC) and Tropical Cyclone Warning Centers (TCWC) participating in the WMO Tropical Cyclone Programme

For the more data-oriented industry professional, satellite data are provided through various data and tools:

-       NOAA/STAR channel loops multibands (1-16) can be downloaded here for your own analysis and projects 

-       NASA Cyclone Global Navigation Satellite System (CYGNSS) data since 2016 including wind speed, soil moisture and more here

-       This can be used alongside NOAA cones trajectory data to forecast using these tools downloadable for free! Isn’t this amazing?

A perfect example of a fully synergic use of the full remote sensing technology stack with advanced technologies (GIS, AI, ML, Web) to paint the richest picture possible of what is going on and support and provide human-centric solutions. Moreover, this data can be accessed by researchers, academics and anyone involved in severe weather events that allows the development and improvement of instruments, information and modelling and products and applications that can support our society in addressing a key challenge of climate change and trying to mitigate some of the damage it causes.

In conclusion, despite the devastating impact on human life, natural disasters have always been a part of our existence – yet the accumulated impacts of human activities resulting in climate change are seemingly increasing the frequency and strength resulting in the need to think, design and build infrastructure that can withstand or be prepared. More importantly, it shows the positive impact that the use of technology can play in preparing for such incidents and at the same time providing evidence to support our need as a society to change the way we think about how we live with nature.

At Minesat, we see the holistic approach to remote sensing integrated with the wider technology and human context NASA and NOAA are undertaking, as a perfect example of demonstrating our message and supporting positive social and environmental change.

For reference to the key articles you can read more on the ‘Hurricane Hunters’, the NOAA news release and a fantastic video on doing the job YouTube. Enjoy!