Category Archives: Hurricane Research

Scientists at NOAA’s Atlantic Oceanographic and Meteorological Laboratory are at the forefront of hurricane research to improve track and intensity forecasts. Every hurricane season they fly into storms, pour over observations and models, and consider new technological developments for how to enhance NOAA’s observing capabilities. The 2014 hurricane season will provide an opportunity to test some of the most advanced and innovative technologies, including unmanned hurricane hunter aircraft and sea gliders, which will help scientists better observe and, eventually, better predict a storm’s future activity.

The game plan: where we are and where we need to be

NOAA’s Aircraft Operations Center (AOC) maintains two P-3 Orions and a Gulfstream IV jet for hurricane observations. To collect data, NOAA’s hurricane researchers fly aboard these aircraft into and around the periphery of storms. A primary tool they use for measuring the hurricane environment is the dropsonde, a lightly weighted cylindrical tube equipped with a parachute and global positioning system technology. Dropsondes transmit their position every half second as they drift through a storm. These mini-weather stations are deployed from the belly of the aircraft and fall towards the ocean, sending data such as pressure, temperature, wind speed, wind direction, and moisture to scientists aboard the hurricane hunter aircraft.

NOAA’s P-3 Orion and G-IV jet. Photo credit: NOAA

While dropsondes are an excellent tool for measuring a storm’s atmospheric environment, their spatial coverage is limited. Dropsondes essentially obtain vertical profiles of a storm at discrete points. Other instruments on the aircraft measure storm properties at altitudes as great as 60,000 feet. However, NOAA’s hurricane hunter aircraft are unable to fly below 5,000 feet due to the extreme turbulence occurring between the ocean and atmosphere. This leaves a gap in the opportunity to collect potentially important data from the lower part of the storm, which may be essential to increasing the understanding of intensity change.

Congressional funding supports new unmanned aircraft

Post-Hurricane Sandy federal funding, the Disaster Relief Appropriations Act of 2013, provided NOAA with the opportunity to test new technology in hopes of better understanding and evaluating storm physics that drive intensity change. An unmanned weather drone, called the Coyote, will do just that.  The Navy originally designed the Coyote for maritime surveillance. NOAA plans to transition this unique platform into a “smart sonde” that can be used for hurricane science. During the 2014 hurricane season, the Small Unmanned Aircraft Vehicle Experiment will test the capability of the Coyote in storms, observing how well it handles severe winds and the harsh hurricane environment.

Scientists will deploy the seven pound unmanned aircraft from the P-3 Orion in the same way as the dropsondes. However, instead of drifting downward towards the ocean surface, the Coyote will open its six-foot wingspan and fly through the storm.  It can be controlled from miles away but will typically be piloted by scientists onboard the P-3s. Its relative lightweight design requires the Coyote to fly with the wind currents, but it will be directed up, down, and sideways to navigate specific flight patterns to measure the inner core and lowest altitudes of the storm.

Hurricanes are fueled by warm ocean water, and vital information needed to better understand and predict intensity change may rest close to the sea surface where manned aircraft cannot fly and the dropsondes only pass through for a few seconds. With its ability to fly for two hours in this region, the Coyote provides the opportunity for much more complete data collection, in comparison to the traditional dropsonde.

Adding a new twist to existing technology The traditional dropsonde itself will also receive an upgrade for the 2014 season with the addition of a sensor to measure sea surface temperature at splashdown. This additional last data point will provide a critical piece of information at the air-sea interface, the environment where energy transfer occurs and is most challenging to observe in a hurricane environment. (image credit: NCAR)

Diving into the ocean to improve hurricane forecasts

The 2014 season will also feature two sea gliders, remotely operated profiling instruments that dive below the ocean surface and then resurface to transmit observations of temperature and salinity. NOAA is testing two ocean gliders in critical hurricane regions of the Caribbean north and south of Puerto Rico. The gliders were deployed in July and will be recovered at the end of hurricane season.  The gliders will profile the upper ocean about 10 times daily, diving to a depth of 1,000 feet and collecting data as they ascend. When a sea glider breaks the surface, its data will be transmitted to AOML and made available in near-real time via the web.

Two gliders ready for deployment from the R/V Sultana,

off the coast of Puerto Rico (credit: NOAA/AOML)

In addition to these new technologies, the Disaster Relief Appropriations Act of 2013 also provided funding to assess the impact of data from these and other instruments in hurricane forecast models. AOML will make use of its Observing System Simulation Experiment expertise to evaluate how such ocean observations can best improve hurricane forecasts of track and intensity change.

The Hurricane Research Division is one of AOML’s three scientific research divisions. Scientists with HRD, and its precursors, have been flying into hurricanes for almost 60 years and regularly collaborate with other federal, university, and international  partners to leverage that expertise to advance hurricane science and forecasting globally. Follow the latest HRD activities during this research season on Twitter or by visiting the division website.

Originally Published August 2014 by Shannon Jones

Dr. Joe Cione of AOML’s Hurricane Research Division displays the Coyote UAV (Credit NOAA/AOML)

NOAA hurricane hunters are prepared to enter a new chapter in the use of unmanned aircraft systems: deploying an unmaned aircraft from an airplane inside a hurricane. Starting on September 14, 2014, NOAA’s hurricane hunting manned aircraft fleet will fly into position to observe any developing tropical systems in the Atlantic using this new tool. The Coyote unmanned aircraft will be the first unmanned aircraft deployed directly inside a hurricane from NOAA hurricane hunter aircraft. The goal of the Coyote is to collect temperature, pressure and wind observations below 3,000 feet, where manned aircraft can not fly safely.

The Coyote UAS is ready to launch. (Credit: NOAA/AOML)

Post-Hurricane Sandy federal funding, the Disaster Relief Appropriations Act of 2013, provided NOAA with the opportunity to test this new technology in hopes of better understanding and evaluating how storms evolve and intensify.

This new unmanned aircraft will do just that.  The Navy originally designed the Coyote for maritime surveillance. NOAA is using it now for hurricane science.

During the 2014 hurricane season, the Small Unmanned Aircraft Vehicle Experiment will test the capability of the Coyote in storms, observing how well it handles severe winds and the harsh hurricane environment.

Scientists aboard NOAA’s P-3 Orion aircraft will deploy the seven-pound unmanned aircraft from a free fall chute in the belly of the plane. The Coyote is designed to then

Chute on P3 used to launch the Coyote. (Credit: NOAA/AOML)

open its six-foot wingspan and fly through the storm. It can be controlled from miles away but will be piloted by scientists onboard the P-3s. Its relative lightweight design requires the Coyote to fly with the wind currents, but it will be directed up, down, and sideways to navigate specific flight patterns to measure the storm’s inner core and storm activity at the lowest altitudes.

Hurricanes are fueled by warm ocean water, and vital information needed to better understand and predict intensity change may rest close to the sea surface where manned aircraft cannot fly. With its ability to fly for up to two hours in this region, the Coyote will provide much more complete data than traditional air-deployed weather instruments, called dropsondes.

NOAA conducted a test-launch of the coyote from the NOAA P-3 aircraft in early September. That successful flight demonstrated the capability of the unmanned aircraft to exit the aircraft, spread its wings, execute flight maneuvers at the commend of a pilot on the P-3, and collect and transmit meteorological observations back to the P-3.

The crew monitors the in-flight Coyote UAS from the piloting station on the P3. (Credit: NOAA/AOML)

In addition to providing support for testing  new technologies, the Disaster Relief Appropriations Act of 2013 also provided funding to assess of the value of incorporating data from these and other instruments to hurricane forecast models. NOAA’s Atlantic Oceanographic and Meteorological Lab  will evaluate how such ocean observations can best improve hurricane forecasts of track and intensity change.

Originally Published in September 2014 by Shannon Jones

Gliders Patrol Ocean Waters with a Goal of Improved Prediction of Hurricane Intensity

 (This feature represents an ongoing mission or event. Most recent updates can be found by scrolling to the bottom of the page)

2014 Glider Mission:

Scientists at NOAA’s Atlantic Oceanographic and Meteorological Laboratory are in the Caribbean to launch two underwater gliders from a vessel off Puerto Rico to collect temperature and other weather data to improve hurricane forecasting.

One of the gliders will collect observations in the Caribbean Sea, and another in the North Atlantic Ocean. They are positioned to operate over the next six months (June-November) collecting data in areas where hurricanes are common and areas where there is a lack of environmental data.

“The goal of the research is to see how these unmanned tools can help us to gather unique observations initialize and evaluate ocean models used for hurricane predictions,” said Gustavo Goni, director of AOML’s Physical Oceanography Division and lead investigator on the project. “This experiment will also help assess the impact of these types of ocean observations in hurricane forecasts using observing system simulation experiments.”

Preparing to Deploy the First Glider  

The gliders will collect data on temperature and salinity from the surface of the ocean down to 1000 meters over the next six months through the rest of the Atlantic hurricane season.

The two gliders are being deployed with the help of scientists and students from the University of Puerto Rico, who are partners in the project along with the Maritime Authority of the Dominican Republic. The university contributed its research vessel, La Sultana, for the deployments. University students assisted with the deployment and will assist with data collection.

The underwater gliders are durable, autonomous, and powered by battery.  Scientists from AOML, with support from NOAA’s National Data Buoy Center, steer the gliders remotely using computers. They will traverse the two regions (identified in the image below), making repetitive dives as they descend and ascend back and forth, weaving through the upper 1000 meters of the ocean.  As the gliders reach the ocean surface at the end of each dive cycle they will transmit their data in real-time to be used by scientists all over the through the Global Telecommunications System.

These observations are a component of AOML’s Hurricane Research Division’s field program and will be used to analyze thermal conditions of the upper ocean and to evaluate existing ocean models, with the goal of improving our understanding of the role the ocean plays in the formation and intensification of tropical cyclones.

The project is funded through the Disaster Relief Appropriations Act of 2013 and AOML. It is a partnership between NOAA’s AOML, NDBC, and Environmental Modeling Center, the University of Miami’s Cooperative Institute of Marine and Atmospheric Studies, University of South Florida, the University of Puerto Rico at Mayaguez, and the Maritime National Authority of the Dominican Republic.

Update: October 2014

AOML’s two underwater gliders recently completed their one thousandth dive.

Since late July, both gliders have provided temperature and salinity profiles down to 1000 meters from the Caribbean Sea and Tropical North Atlantic Ocean. The data collected by these gliders include observations made during Tropical Storm Bertha and Hurricane Gonzalo. The gliders will continue to record temperature and salinity profiles until their planned recovery during the week of November 17th.

The glider located in the Tropical North Atlantic, north of Puerto Rico, was situated close to the path of Hurricane Gonzalo.  During Gonzalo’s passage, the glider obtained information on how the storm’s winds altered local ocean temperature and salinity conditions. Observations show changes in salinity and temperature in the upper 100m due to mixing. Two days after the passage of the storm, the glider moved northward to obtain more information from areas traveled by Hurricane Gonzalo.

Data from this underwater glider were used in real-time numerical model intensity forecasts.  In addition, this data will be analyzed in combination with those obtained during Hurricane Bertha, which also traveled over this same glider. Oceanographers will assess the impact of this data on the Tropical Cyclone intensification forecasts.  The main goal of this project is to provide ocean observations to help assess the impact of these observations on tropical cyclone intensity forecast, and of seasonal forecasts.

Update: November 2014

On November 18-19th, researchers with AOML’s Physical Oceanography Division (PhOD) successfully recovered their two underwater gliders in the North Atlantic Ocean and Caribbean Sea from the RV La Sultana of the University of Puerto Rico Mayaguez (see map below for recovery locations). These recoveries marked the end of the first underwater glider mission for AOML, which started in mid July 2014.

The recovery involved a field team at sea retrieving the gliders and a pilot team at AOML controlling the gliders and steering them to an area where they could be safely recovered. PhOD-University of Miami Cooperative Institute personnel Grant Rawson and Kyle Seaton participated in their at-sea recovery, while PhOD personnel Francis Bringas and Gustavo Goni provided the piloting support from AOML.

2015 Glider Mission:

AOML’s 2015 underwater glider campaign started successfully with the deployment of two gliders in the Caribbean Sea off Puerto Rico. AOML and partners deployed the underwater gliders on February 6, 2015. The gliders’ second mission will transect a region in the eastern Caribbean Sea providing approximately 3000 profile observations of temperature and salinity until their planned recovery in April 2015.

 

Professor Julio Morell and Luis Pomales of The University of Puerto Rico at Mayaguez deploy the underwater glider. Photo Credit: NOAA/AOML

What’s new? During this mission, in addition to temperature and salinity data, the gliders now feature oxygen sensors that can measure dissolved oxygen during the ocean profiles. This new addition will help scientists learn about changes in oxygen in the upper ocean which might impact ecosystems in the Caribbean Sea. During hurricane season, the oxygen sensor will be used by scientists to monitor how dissolved oxygen is affected by the passage of a storm. Scientists also completed a firmware update which allows collection of pH profile data by using the sensors already installed in the gliders. Data from this mission will allow scientists to observe upper ocean conditions in this area to help seasonal forecasts of the Atlantic Warm Pool.

More information about the locations of gliders, data, and a summary of objectives can be found at AOML’s glider program page.

While tropical cyclones can dramatically impact coral reefs, a recent study reveals their passage also exacerbates ocean acidification, rendering reef structures even more vulnerable to damage. Calcifying marine organisms such as corals that thrive in alkaline-rich waters are increasingly imperiled as seawater becomes more acidic due to the ocean’s uptake of carbon dioxide. The detrimental effects upon these organisms have been documented, but less is known about how reefs might react to ocean acidification when coupled with an additional stress factor such as a tropical cyclone.

To assess how reefs might respond to such a scenario, coral researchers Derek Manzello, Ian Enochs, and Renee Carlton from the Cooperative Institute for Marine and Atmospheric Studies at the University of Miami’s Rosenstiel School and NOAA’s Atlantic Oceanographic and Meteorological Laboratory, along with researchers from the University of Washington and NOAA’s Ocean Acidification Program, collected data from reefs in the Florida Keys before, during, and after the passage of Tropical Storm Isaac in August-September 2012. Their findings appear online in the Journal of Geophysical ­Research.

Tropical Storm Isaac as it passes over the Florida Keys on August 26, 2012. Image Credit: NOAA

The team analyzed seawater carbonate chemistry and environmental data from Cheeca Rocks and Little Conch Reef, both coral monitoring sites, as well as data from a coastal marine automated network station at Molasses Reef.

They found that Tropical Storm Isaac caused both an immediate and prolonged decline in seawater pH and carbonate saturation state at the two coral reef sites studied. The post-storm pH levels were the lowest recorded values to date from over two years of high-resolution data measured at the Cheeca Rocks ocean acidification monitoring site, and this depression in pH lingered for more than a full week.

Prior concerns regarding ocean acidification and coral reefs assumed carbonate undersaturation would not occur at reefs in the foreseeable future due to their location within the highly supersaturated tropical oceans. However, the study demonstrates that carbonate undersaturation at reefs will occur from even the passage of a modest tropical storm when coupled with ocean acidification.

Coral bleaching at Cheeca Rocks in the Florida Keys. Image credit: NOAA

With climate models projecting a steady increase in the rate of ocean acidification, along with stronger, more frequent tropical cyclones, the future for coral reefs thus appears bleak. In the coming decades, tropical cyclones could depress carbonate seawater saturation ­levels to such an extent that reefs will undergo periods of post-storm dissolution, weakening coral reef frameworks and worsening the widespread ecological and economic consequences of the coral reef crisis.

NASA’s Global Hawk departs for its mission out of NASA’s Wallops Flight Facility near Chincoteague, Va. (Photo credit: NASA)

NOAA hurricane scientists are expanding their observations this summer, working with NASA’s Hurricane and Severe Storm Sentinel (HS3) mission and its innovative Global Hawk unmanned aerial vehicles to push the boundaries of hurricane operations. NASA looked to NOAA’s hurricane experts to augment its HS3 science team, supporting their five-year mission to investigate the processes that underlie hurricane formation and intensity change in the Atlantic Ocean basin.

The Hurricane Research Division at AOML has a long history of using NOAA’s P-3 Orions and the G-IV jet hurricane hunter aircraft to observe the inner core and environment of these storms, studying the dynamics of structure and intensity change. The P-3’s often fly right through the eye of hurricanes to collect observations, where small parachuted instruments called dropsondes are deployed to collect temperature and pressure data and measure wind-speed. AOML pioneered the use of these instruments in hurricanes and are world experts in the requisite data processing and real-time transfer of data to operational modeling centers and NOAA’s National Hurricane Center.

NASA worked with NOAA’s Earth System Research Laboratory and its engineering partners at the National Center for Atmospheric Research to re-design and implement as autonomous dropsonde system for the Global Hawks platform. Hurricane researchers at AOML process data obtained from the dropsonde system and with 26 hours of flight time per mission that can mean up to 89 drops per flight.

Each HS3 flight averages three times the length of a traditional hurricane hunter flight, allowing the aircraft to fly further and much higher than the flight path of the NOAA P-3’s. This expanded flight track allows the Global Hawks to directly sample regions of the Atlantic typically only observed via satellites. One type of large-scale feature that is of particular interest is Saharan dust storms.

These dust storms bring a massive layer of very dry air out over the Atlantic Ocean, known as the Saharan Air Layer, or SAL.  Scientists believe that this injection of extremely dry air into the birthplace of Atlantic hurricanes inhibits storm development. A SAL has been present in the eastern Atlantic since July and continues to interact with nascent tropical waves rolling off of Africa.

This summer NOAA and NASA scientists will coordinate Global Hawk flights along with NOAA’s hurricane hunter aircraft to observe the convection that drives intensification within the core of hurricanes, as well as the broader environment that may influence track as well as intensity.

In its 2013 Atlantic hurricane season outlook issued today, NOAA’s Climate Prediction Center is forecasting an active or extremely active season this year.

For the six-month hurricane season, which begins June 1, NOAA’s Atlantic Hurricane Season Outlook says there is a 70 percent likelihood of 13 to 20 named storms (winds of 39 mph or higher), of which 7 to 11 could become hurricanes (winds of 74 mph or higher), including 3 to 6 major hurricanes (Category 3, 4 or 5; winds of 111 mph or higher).

These ranges are well above the seasonal average of 12 named storms, 6 hurricanes and 3 major hurricanes.

“With the devastation of Sandy fresh in our minds, and another active season predicted, everyone at NOAA is committed to providing life-saving forecasts in the face of these storms and ensuring that Americans are prepared and ready ahead of time.” said Kathryn Sullivan, Ph.D., NOAA acting administrator. “As we saw first-hand with Sandy, it’s important to remember that tropical storm and hurricane impacts are not limited to the coastline. Strong winds, torrential rain, flooding, and tornadoes often threaten inland areas far from where the storm first makes landfall.”

Three climate factors that strongly control Atlantic hurricane activity are expected to come together to produce an active or extremely active 2013 hurricane season. These are:

• A continuation of the atmospheric climate pattern, which includes a strong west African monsoon, that is responsible for the ongoing era of high activity for Atlantic hurricanes that began in 1995;
• Warmer-than-average water temperatures in the tropical Atlantic Ocean and Caribbean Sea; and
• El Niño is not expected to develop and suppress hurricane formation.

“This year, oceanic and atmospheric conditions in the Atlantic basin are expected to produce more and stronger hurricanes, said Gerry Bell, Ph.D., lead seasonal hurricane forecaster with NOAA’s Climate Prediction Center. “These conditions include weaker wind shear, warmer Atlantic waters and conducive winds patterns coming from Africa.”

NOAA’s seasonal hurricane outlook is not a hurricane landfall forecast; it does not predict how many storms will hit land or where a storm will strike. Forecasts for individual storms and their impacts will be provided throughout the season by NOAA’s National Hurricane Center.

New for this hurricane season are improvements to forecast models, data gathering, and the National Hurricane Center communication procedure for post-tropical cyclones. In July, NOAA plans to bring online a new supercomputer that will run an upgraded Hurricane Weather Research and Forecasting (HWRF) model that provides significantly enhanced depiction of storm structure and improved storm intensity forecast guidance.

Also this year, Doppler radar data will be transmitted in real time from NOAA’s Hurricane Hunter aircraft. This will help forecasters better analyze rapidly evolving storm conditions, and these data could further improve the HWRF model forecasts by 10 to 15 percent.

The National Weather Service has also made changes to allow for hurricane warnings to remain in effect, or to be newly issued, for storms like Sandy that have become post-tropical. This flexibility allows forecasters to provide a continuous flow of forecast and warning information for evolving or continuing threats.

“The start of hurricane season is a reminder that our families, businesses and communities need to be ready for the next big storm,” said Joe Nimmich, FEMA associate administrator for Response and Recovery. “Preparedness today can make a big difference down the line, so update your family emergency plan and make sure your emergency kit is stocked. Learn more about how you can prepare for hurricane season at www.ready.gov/hurricanes.“