Ellen Gray – NASA Disaster Response

NASA Prepares for Hurricane Zeta

A natural-color image of Hurricane Zeta (above) was acquired in the late morning on October 28, 2020, by the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite. Cameras mounted on the International Space Station captured video footage of the storm (below) just before 1 p.m. that day. Credit: NASA’s Earth Observatory

By Jacob Reed, NASA Earth Applied Sciences Disaster Program

As Tropical Storm Zeta makes landfall on the U.S. Gulf Coast, NASA has eyes on the storm with an array of Earth-observing instruments and stands ready to aid affected communities with critical data and analysis.

Zeta is following a path similar to Hurricane Delta, which after crossing the Yucatan Peninsula made its way across the Gulf of Mexico and struck the Louisiana coast as a Category 2 hurricane on October 9. As Zeta makes landfall along the northern Gulf Coast, it’s the 7th named storm to do so in this record-breaking season, following Tropical Storm Cristobal, Hurricane Laura, Tropical Storm Marco, Hurricane Sally, Tropical Storm Beta, and Hurricane Delta.

Tropical Storm Zeta is the 27th named storm of 2020, which ties the record with 2005 for the most named storms. The 2020 season is also only the second time in recorded history (the other being 2005) that the Greek alphabet has been used because the number of named storms has exceeded the number of regular names on the list. With several weeks still left in the 2020 hurricane season, 2020 is expected to surpass this previous record for most named storms in one season.

Mapping Rainfall Rates and Structure

Zeta originated in the western Caribbean from a broad area of low pressure. Originally inhibited by changes in wind speeds and directions – also known as wind shear – the system was slow to develop. But by the late afternoon of Saturday October 24, the National Hurricane Center (NHC) reported that a tropical depression had formed, the 28^th of the season. Nine hours later the system was upgraded to a tropical storm and given the name Zeta. Over the next twelve hours, Zeta remained nearly stationary and unable to intensify further. It was at about this time that the Global Precipitation Measurement Mission (GPM) Core Observatory satellite flew over Zeta at 2:15pm CDT (19:15 UTC), as shown in the animation.

GPM overpass of Tropical Storm Zeta on October 25 at approximately 2:15pm CDT (19:15 UTC). Half-hourly rainfall estimates from NASA’s multi-satellite IMERG dataset are shown in 2D on the ground, while rainfall rates from GPM’s DPR instrument are shown as a 3D point cloud, with liquid precipitation shown in green, yellow and red, and frozen precipitation shown in blue and purple. Credit: NASA Goddard Scientific Visualization Studio

Here, rainfall rates derived from the GPM Microwave Imager (GMI) and Dual-frequency Precipitation Radar (DPR) instruments provide a detailed look at Zeta. While broad bands of rain circle the storm, GPM shows that the center itself is ragged and the eye of the storm is asymmetric. Warm, moist air rising up through the atmosphere (shown by the blue surface indicating the top heights of rain clouds) is producing very heavy rainfall (shown in dark red and magenta) near the center. These processes release heat near the center of the circulating storm, helping to consolidate it. At the time of the overpass, Zeta was still classified as a weak tropical storm with maximum sustained winds reported at 40 mph by the National Hurricane Center.

Zeta began to slowly but steadily strengthen, becoming a strong tropical storm overnight with sustained winds just below hurricane intensity early the next morning. Finally, at 2:10pm CDT on the October 26, Zeta reached hurricane intensity.

At this time Zeta was about 105 miles southeast of Cozumel, Mexico and moving northwest. Zeta would go on to make landfall near Tulum at 11:10pm CDT as a Category 1 storm with maximum sustained winds reported at 80 mph by the National Hurricane Center. After crossing the Yucatan Peninsula, Zeta weakened back down to a tropical storm, but re-emerged over the southern Gulf of Mexico. Surface water temperatures were running slightly above normal in this area – still at or above ~82.4 F (28 C), which is well above the ~78.8 F (26 C) typically needed to allow for intensification.

GPM Core Observatory overpass of Tropical Storm Zeta on October 28 at approximately 3:25am CDT (8:25 UTC). Credit: NASA Goddard Scientific Visualization Studio

GPM flew over Zeta again early the morning of October 28, around 3:25am CDT (8:25 UTC) as it was strengthening in the Gulf of Mexico and headed for landfall in southeastern Louisiana. Data captured by the DPR show a symmetric storm, with a clear eye surrounded by tall thunderstorms—an indicator that the storm was strengthening after encountering the Yucatan Peninsula a day earlier.

Shortly after this overpass, the National Hurricane Center reported that Zeta had re-intensified to a Category 1 hurricane, and the NHC currently says Zeta is a Category 2 hurricane as it makes landfall along the southern coast of Louisiana Wednesday evening.

Cameras outside the International Space Station captured dramatic views of Hurricane Zeta at 12:50 pm ET October 28, as it churned 200 miles south-southwest of New Orleans packing winds of 90 miles an hour. Credit: NASA

Aiding Risk Reduction, Response and Recovery

To aid local communities in preparing for and recovering from hurricanes and other disasters, the NASA Earth Applied Sciences Disasters Program coordinates a team of experts across NASA centers to provide vital Earth-observing data and analysis. For Hurricanes Laura, Sally, and Delta, the program worked closely with stakeholders from the Federal Emergency Management Agency (FEMA), the Louisiana National Guard, and the Alabama Emergency Management Agency to provide guidance and analysis both in meetings and through data distributed on the NASA Disasters Mapping Portal. Near real-time data for tracking the storm is also made available on the portal’s Tropical Cyclone Dashboard. The program stands ready to continue to work with these agencies and provide assistance for Hurricane Zeta should the need arise.

Combining multiple datasets and tools allows NASA to see the big picture of a storm and its impacts, and helps answer broader questions about how communities can better prepare for, and recover from, the storms of the future. For Hurricane Zeta, researchers will have a unique opportunity to gauge the vulnerability or resilience of a region that was recently impacted by several destructive storms, and to study their compounding effects. Attempting to determine what damage was caused by which storm will be a challenging task on its own. However, attempting to answer these tough questions can provide critical guidance to help communities build back better and strengthen them for the disasters and challenges that lie ahead.

Mapping Burned Areas From Southern California’s Bobcat Fire

A damage assessment map showing areas in Angeles National Forest that were likely damaged from the Bobcat Fire on September 7th, 8th, 13th, and 14th. Credits: Alaska Satellite Facility, NASA-JPL/Caltech, European Space Agency, NASA Earth Applied Sciences Disasters Program. — A damage assessment map showing areas in Angeles National Forest that were likely damaged from the Bobcat Fire on September 7th, 8th, 13th, and 14th. **Credits:** Alaska Satellite Facility, European Space Agency, NASA Earth Applied Sciences Disasters Program. The image contains modified Copernicus Sentinel data (2020), processed by ESA and analyzed by the NASA-JPL/Caltech ARIA team.

As wildfires continue to rage in the western U.S., NASA’s satellites are helping to track the burned areas and map damage in California and beyond.

One of those fires is the Bobcat Fire in Southern California, which has burned over 100,000 acres – making it one of the largest fires in Los Angeles County’s history. The Damage Proxy Map above shows areas in Angeles National Forest that were likely burned from the Bobcat Fire, ranging from moderate (yellow) to severe fire damage (red). Comparing the maps from September 7^th, 8^th, 13^th and 14^th shows how the fire spread over the course of the week, and how close the Bobcat Fire came to roads and other infrastructure.

NASA scientists with the Advanced Rapid Imaging and Analysis (ARIA) team at NASA’s Jet Propulsion Laboratory and California Institute of Technology created the maps using satellite data collected before and during the fires.

The NASA Earth Applied Sciences Disasters Program is working to provide maps like this one and other materials to regional agencies – including the California State Guard and the Federal Emergency Management Agency – to improve understanding of the impacts from the western U.S. fires and the potential risks to people, infrastructure, and the environment. Learn more about NASA’s efforts supporting the western U.S. fires on the NASA Disasters Mapping Portal and NASA Disasters website. – Sofie Bates

Highlights of How NASA’s Disasters Team Helps Reduce Risk

The International Day of Disaster Reduction 2018 is on October 13, and NASA is marking the occasion by sharing highlights of how we provide data to support disaster reduction and help improve recovery efforts. The NASA Disasters Team, a part of the Applied Sciences Program within NASA’s Earth Science Division, promotes the use of streamed data to prepare for, respond to and recover from natural and technological disasters. The NASA Disasters team targets a spectrum of disasters including floods, earthquakes, volcanoes, landslides, and oil spills, as well as assesses hazards to vulnerable populations and livelihoods.

Here’s a few ways in which the Disasters Team is working to reduce risk:

The Atmospheric Infrared Sounder (AIRS) onboard NASA's Aqua satellite shows Hurricane Michael on October 10, 2018. — The Atmospheric Infrared Sounder (AIRS) onboard NASA’s Aqua satellite shows Hurricane Michael on October 10, 2018. Credit: NASA JPL-Caltech

NASA’s AIRS instrument was used to support disaster risk reduction by providing critical information to Florida emergency managers on the impact of wind direction and speed before Hurricane Michael made landfall.

The Advanced Rapid Imaging and Analysis (ARIA) team created a damage proxy map (close-up right) for Palu, Indonesia. Credit: NASA JPL-Caltech

NASA’s ARIA team created damage proxy maps after the Palu, Indonesia earthquake. These images help governments and responders identify areas that experienced significant damage and allocate resources accordingly to reduce risk.

Radar view of floodwaters in the Carolinas from Hurricane Florence. Credit: NASA — Floodwaters in the Carolinas from Hurricane Florence. Credit: NASA

To support disaster risk reduction NASA developed an airborne radar mission to give agencies like FEMA and the U.S. Forest Service a much-needed view of floodwaters that threatened areas in North Carolina and South Carolina.

Night light show San Juan, Puerto Rico, before Hurricane Maria, 2017. Credit: NASA Goddard — Night lights show San Juan, Puerto Rico, before Hurricane Maria, 2017. Credit: NASA Goddard

NASA used its Black Marble technology to pinpoint where the lights went out after Hurricane Maria devastated Puerto Rico. Knowing where the power is out-and how long the power has been out-allowed first responders to better deploy rescue and repair crews and to distribute life-saving supplies.