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U.S. Naval Oceanography: Pathfinders of the American Military Part II

06 March 2023

From Ed Darack -Weatherwise Magazine

Weather’s Impact on Military Campaigns Historically, weather events have played key roles in outcomes of battles and entire campaigns. This happened famously during the Revolutionary War when George Washington moved much of his army across the East River under cover of fog after the Battle of Brooklyn (also called the Battle of Long Island). Outnumbered and outgunned by the British, fog allowed Washington to move roughly 9,000 of his Continental Army troops across the East River—a move that many historians claim set the stage for victory over the British, as had fog not emerged and had Washington not used it as a cloak, the British would have destroyed his army. The fog was an unpredicted, serendipitous event, one that Washington utilized to his advantage on the spot. In subsequent years, military environmental forecasts have evolved to become much more tightly involved in planning processes.
Weather’s Impact on Military Campaigns
Historically, weather events have played key roles in outcomes of battles and entire campaigns. This happened famously during the Revolutionary War when George Washington moved much of his army across the East River under cover of fog after the Battle of Brooklyn (also called the Battle of Long Island). Outnumbered and outgunned by the British, fog allowed Washington to move roughly 9,000 of his Continental Army troops across the East River—a move that many historians claim set the stage for victory over the British, as had fog not emerged and had Washington not used it as a cloak, the British would have destroyed his army. The fog was an unpredicted, serendipitous event, one that Washington utilized to his advantage on the spot. In subsequent years, military environmental forecasts have evolved to become much more tightly involved in planning processes.
During the planning for Operation Overlord, the allied invasion of Normandy in World War II, forecasts of environmental factors made prior to operational execution played vital roles in ulti­mate success on D-Day. Planners for the operation left absolutely nothing to chance. They took into consideration tides, the phase of the moon for nighttime operations, wind, waves, rain, and even fog, integrating all factors into the plan for the amphibious assault. Crucially, their careful inte­gration of a wide array of weather monitoring sys­tems allowed them to forecast a lull in inclement weather, a break that German forecasters, utilizing a less sophisticated weather monitoring and pro­cessing system than that of the Allies, failed to predict. The Allies pounced during the brief period of correctly predicted calm, a window of opportu­nity that caught the Germans by surprise and led to the Allies defeating them. Accurate environ­mental forecasting proved to be the vital compo­nent for success in the operation.  Other more recent examples, including rain soaking roadways in Ukraine and subsequently inhibiting Russian logistical efforts, demon­strate how monitoring and predicting weather— and utilizing it for tactical and operational advantage—can fend off or defeat an enemy, even a technologically advanced adversary.  There are also examples where weather and environmental factors, not properly forecasted or properly integrated into planning, have led to mil­itary defeat—and sometimes disaster. The 1980 special operations mission to rescue American hostages in Tehran, Operation Eagle Claw, ended in disaster when a Navy RH-53D helicopter crashed into an Air Force EC-130 transport air­craft at a forward staging and refueling point called Desert One, killing eight and severely injuring four. A number of factors contributed to the disas­ter, notably environmental factors. The first envi­ronmental factor was a meteorological condition where fine dust becomes suspended in the atmo­sphere. Called a “haboob” (etymologically derived from an Arabic word meaning “to rush” or “to blow”), this condition is common throughout much of the Middle East and is a form of a sand­storm. The condition reduces visibility to just a few feet. Although weather forecasters properly forecasted that conditions were ripe for haboob formation in the area, this information was never integrated into operational planning due to the nature of the mission’s classification. As a result, the pilots never knew of the environmental threat and the helicopter component of the task force plowed straight through the haboob. The reduced visibility, combined with malfunctions in naviga­tion instruments, caused one of the RH-53Ds to return to the aircraft carrier from which it launched, the USS Nimitz. It also caused a delay in the arrival of the remaining six helicopters at Desert One by 90 minutes.  The second environmental condition that played a key role in the disaster was the surface character of Desert One. An improvised, austere landing zone, it was composed of hardened dirt with loose sand and dust covering the desert floor. With the delay due to the haboob and other fac­tors, the mission was aborted by President Jimmy Carter, via satellite communication. The helicop­ters then needed to refuel for the flight back to the Nimitz. While hovering to maneuver into position to refuel from the EC-130 (which carried fuel in onboard bladders), the rotor wash from the RH-53D produced a “brownout”—a small dust storm. The disoriented pilots careened into the EC-130, causing the explosion of the two aircraft.
A lack of environmental situational awareness culminated in Operation Eagle Claw’s tragic end. The disaster, however, led to enduring military operational benefits. A subsequent investigation into Eagle Claw, led by recently retired Chief of Naval Operations Admiral James Holloway, cre­ated a report that became the primary thrust for a dramatic evolution of the Department of Defense. Called the Goldwater-Nichols Department of Defense Reorganization Act of 1986, the law ush­ered in the modern era of American joint military operations, where all Department of Defense services work together seamlessly in joint unity of effort. Today, environmental situational awareness information—like the predisposition of a desig­nated landing zone to generate brownouts, and the possibility of haboob formation in a region during a certain time of year—is carefully integrated into planning and made available for general opera­tional use throughout all services of the military. It is a result of continuously refined environmental monitoring and forecasting technology, and also a result of joint interoperability structures put in place as a result of the Goldwater-Nichols Act.
Today, countless military operations, from the smallest to largest scale, proceed seamlessly from an environmental standpoint due to detailed operational incorporation of products like those of Meteorology and Oceanography (METOC). Sometimes, however, environmental information from METOC or other Department of Defense fore­casting bodies goes unheeded. While no individual activity in a war zone can ever be considered “rou­tine”—a rubric of vigilance that is emphasized throughout the American military—oversights occur, often due to repetition of action, and this can lead to immense tragedy.  Late in the night of January 25, 2005, two Marine Corps CH-53E Super Stallion helicopters, call signs Sampson 21 and Sampson 22, launched from western Iraq’s Al Asad Airfield. The pilots, operating using night vision goggles, lifted into the night sky on a scheduled transport mission to pick up and drop off personnel throughout bases in the region. It was a type of flight that they had repeated numerous times throughout their deployment to the area of operation. Headed toward Camp Korean Village, a base near the town of Ar-Rutbah about 50 miles from the Syrian border, pilots of the two helicopters noticed visibility degrading shortly after midnight of the 26th. Sampson 21, the lead aircraft, lost contact with Sampson 22 shortly thereafter—never to be regained.  The official report cited spatial disorientation that led to “CFIT” (pronounced “see fit”): con­trolled flight into terrain. The aviators of Sampson 22, disoriented by the lack of visual references within the haboob, inadvertently flew the heli­copter onto a left-hand bank directly into the desert at over 100 mph. All 31 personnel onboard—aircrew and passengers—perished. This was the greatest single incident loss of life for Americans in the Iraq War, the Global War on Terrorism (including the war in Afghanistan, America’s longest in history) and for combat-de­ployed American military personnel since the 1983 Beirut suicide bombing attack that killed 241.  While helicopter shoot-downs and massive improvised explosive device bombings reverberate in memories long after their respective tragedies in recent wars, it was the atmosphere that directly precipitated the Sampson 22 crash, one of greater magnitude than any wrought by the Taliban or Al Qaeda on battlefields in Iraq and Afghanistan.  The official investigation cited an oversight of weather forecasts for the area, which had predicted haboob formation. Historians and military practi­tioners often state that environmental conditions, notably weather, can be a greater enemy than any human force. The Sampson 22 tragedy dramati­cally illustrates this.

At the Forefront of Technology
METOC’s Fleet Weather Center personnel not only provide detailed forecast products but have developed—and continue to refine—an advanced weather intelligence product. It is a weather-based tactical predictive model that fuses multivariate intelligence information with weather data. Hermsdorfer noted that by working with Navy and other U.S. government bodies, patterns of opera­tion of pirates in certain parts of the world emerged, based on weather. With certain weather criteria known—atmospheric events that can be reliably predicted and observed—Fleet Weather Centers can state when a certain region will be essentially guaranteed to be pirate-free for safe passage, and when to be vigilant for attacks, based on the weather in that region. To generate such advanced products, including regular daily regional forecasts, ship- and fleet-spe­cific forecasts, operational forecasts, and weath­er-based predictive analysis products, Naval Oceanography relies on one of the world’s most advanced computing centers, the Fleet Numerical Meteorology and Oceanography Center, or FNMOC, pronounced “fin-mock.” Based in Monterey, California, the Navy established FNMOC in 1961 at the very beginning of the computer revolution—and they helped advance the technology. Today, the command is composed of mathematicians, computer scientists, oceanog­raphers, and naval fleet operational and tactical experts. Personnel operate and source computing power from a range of some of the most powerful computers ever created, including those housed at the Navy Defense Supercomputing Resource Center. They also have dedicated access to the computers of the Department of Defense Supercomputing Resource Center, a unit that pro­vides computing power for a wide range of military initiatives and is sponsored by Naval Oceanography.  FNMOC receives tens of millions of data points per day, according to Captain Christi Montgomery, the unit’s commanding officer. They receive data from a wide variety of platforms, including a num­ber of Navy and NOAA weather satellites, unmanned systems, and manned surface vessels. They regularly generate global and regional weather prediction products, including charts, and a number of regional and fleet- and ship-specific forecasts. With both atmospheric and oceano­graphic data, FNMOC can create extremely accu­rate models, and their base algorithms are continuously being enhanced and refined.  “We have a global atmospheric numerical model, and a global oceanography model, and we have a partnership with the Naval Research Laboratory Marine meteorology division,” explained Captain Montgomery. Furthermore, Captain Montgomery noted, they work with “ensemble” models, where different models, including those from the Air Force, are fused. “We found a lot of success running ensemble models.” One of these is called COAMPS, or Coupled Ocean/Atmosphere Mesoscale Prediction System. FNMOC personnel can create high-resolution predictive analysis oceanography-meteorology models for regions, fleets, or individual ships with this technique. Continuously advancing their techniques and technology, a legacy that dates to the earliest days of the Naval Depot of Charts and Instruments, is a demonstrated component of Naval Oceanography culture, notably at FNMOC. Captain Montgomery explained that they work in-house and with the Naval Research Laboratory to constantly upgrade forecasting. “Research and development transitions directly into naval operations all the time,” she stated.  A sister command to FNMOC, the Naval Oceanographic Office (NAVOCEANO) provides the U.S. military with detailed information vital to maritime operations throughout the globe, including underwater dynamics—oceanographic “weather.” Captain Ken Wallace, the recently departed commanding officer of the unit, explained that, although 70% of the globe is covered by oceans, roughly only 20% of it has been surveyed. “It can be an enemy, but also it can be an advan­tage.” Like the other components of METOC, NAVOCEANO continuously seeks to always maintain a tactical and operational edge through knowledge of the environment. The command ingests massive troves of data every day, including information from satellites, manned surface and subsurface vehicles, unmanned aircraft, unmanned underwater vehicles, and specialized buoys, both fixed and drifting. One of the most important types of craft used is the oceanographic survey ship, or T-AGS, pronounced “tags.” “These ships are always forward deployed,” Captain Wallace explained of the specialized data collection vessels that rank as some of the busiest in the Navy. They collect a wide spectrum of oceanographic data, including CTD (conductivity, temperature, and depth) and a number of other criteria. Wallace explained that these ships scan columns of ocean water from the seafloor to the surface, and the data collected is then fed into computers at FNMOC. Survey detachments travel throughout the globe, often battling extreme ocean conditions. “They are out there fighting heavy seas, in places where no other ships go, in inclement weather, so we understand and characterize a very complex ocean environment.” The data collected by NAVOCEANO provides the Navy with “safety of navigation support,” meaning the ability to navigate throughout the world’s oceans—and under them.

Underwater Warfare Weather Forecasting
Underwater warfare is one of the most techni­cally difficult, dangerous, and secretive of all types of military operations. Naval Oceanography is the key enabler of underwater navigation for the U.S. Navy’s submarines. The data col­lected—and then processed into continuously evolving products, notably digital charts— allows American submarines to roam the oceans freely. Using different types of sonar systems, including side-scan sonar, from both manned and unmanned platforms, the NAVOCEANO continuously gathers bathymetric data (under­water topography) of areas of interest to the Navy. Working with the National Geospatial- Intelligence Agency (charged with making maps and charts or the Department of Defense), the office then produces detailed information prod­ucts. Because GPS signals cannot penetrate water, and because they have no means (like windows) of directly visualizing their surround­ings while submerged, submarines rely primarily on inertial systems to determine their location as they ply the dark depths. Extremely sensitive gyroscopes and accelerometers, which detect movement and direction changes, internally track the motion of submarines, and hence loca­tion from a known reference position. While submarines possess active sonar that can be used for navigation, the use of such systems alerts potential enemies to the presence of the subma­rine emitting these “pings,” so this form of nav­igation is used judiciously. Accurate, up-to-date, and extremely detailed underwater charts are critical for submarine operations to proceed without potentially deadly collisions, where inertial navigation and METOC information alone guide them.
Just as important to submarine operations is dynamic hydrographic data—“underwater weather.” Submarines use passive sonar—essentially extremely sensitive microphones—to detect potential enemy vessels. To accurately identify the location and range of a detected enemy boat, submarine warfare spe­cialists need to know how sound waves will be refracted (bent) as they are emitted from the enemy target to their submarine’s microphones. Temperature, salinity, density, and ocean currents determine this. Even being slightly off with any of these criteria can prove deadly in actual combat. Any action by one submarine, like launching a tor­pedo, gives the other positional data through acoustics.  Hydrographic dynamics also affects subma­rine communication, which is limited to acous­tic systems and extremely long wave radio waves (wavelengths of tens or hundreds of miles), both severely limited compared to communication above water. One of the most important com­ponents of America’s strategic capability is the U.S. Navy’s fleet of SSBNs, ballistic missile sub­marines. These boats, which each carry up to 24 Trident II SLBMs (submarine launched ballistic missiles), silently lurk in key areas of the world’s oceans. When tasked to execute their mission, these submarines need to know the specific dynamics of the water in which they are oper­ating to ensure that they can receive such a message. The Naval Oceanography Office ensures that SSBN communications specialists will be able to receive such a message by provid­ing them with detailed information about the water in which they are deployed.  One of the most complex forms of naval war­fare is ASW (anti-submarine warfare). NAVOCEANO is the key enabler for the U.S. Navy in this mission. The science involves fus­ing bathymetric data with underwater dynamics data to provide American attack submarines a “blank canvas”—a picture of the native envi­ronment, free of any enemy presence. By scan­ning a region using passive sonar, Naval specialists can detect any “brushstroke” of an enemy on this canvas, and can then move in and attack, using active sonar (which also requires detailed knowledge of the water’s char­acter to the work properly) to provide high-res­olution targeting data.  Naval Oceanography also is a key enabler of military operations in one of the most import­ant of all environment types, the transition of sea to land, littoral zones. Called Fleet Survey Teams, this small component of Naval Oceanography will prove to be one of the most important in all of the Department of Defense if war should break out requiring amphibious operations where Marines and other personnel land on beachheads using amphibious assault craft. Historically, the importance of optimized environmental situational awareness in littoral combat is best exemplified by the successful Normandy landings at D-Day of Operation Overlord. Failure to adequately incorporate meteorological and oceanographic information into a mission plan is best illustrated by November 1943’s Battle of Tarawa. Planners had predicted that a rising tide would provide five feet of water depth over coral reefs. They failed to predict the neap tide (when there is the least difference between high and low water), which prohibited their landing craft from making it through the littoral zone. Although they ultimately achieved victory, the Marines suffered severe losses due to the over­sight of environmental factors.  Today, Fleet Survey Team detachments, which can operate from shore or ship, carefully survey littoral zones of interest, ensuring freedom of passage for American forces. They provide tide information (often down to the inch), locations of wrecks and submerged rocks, and other hazards. Fused with Naval Oceanography’s meteorological forecast products, Fleet Survey Team data collection ensures that any future amphibious assault proceeds like the advance at Normandy, and not as experienced at Tarawa.
Specialized Personnel
While Naval Oceanography covers a very broad range of environmental criteria, the command’s greatest strength is its composition of high­ly-specialized personnel. Many personnel begin their Navy careers in other fields, then “laterally move” into Naval Oceanography. This brings a diversity of backgrounds which helps the over­all command provide relevant information, often custom tailored, to individual specific applications. Component commands of Naval Oceanography are similarly diverse and highly specialized. This includes the Naval Ice Center. work of which is vital in understanding route-finding in cold and high-latitude portions of the globe, and the Joint Typhoon Warning Center, which provides detailed information on the globe’s most powerful storms.  Operationally, Naval Oceanography supports all types of Department of Defense missions, including special operations. The Naval Oceanography Special Warfare Center (NOSWC) directly supports special operations from an ocean­ography and meteorological standpoint. Members of this component of Naval Oceanography train and deploy with special operations units, and sometimes accompany them on operations. Commander Mark Hebert, the commanding offi­cer of NOSWC, provides a general overview of the command: “The mission of the Naval Oceanography Special Warfare Center (NOSWC) is to deploy full-spectrum Meteorology and Oceanography (METOC) teams to provide asym­metric warfighting advantage for Naval Special Warfare (NSW) globally. Many people equate NSW to Sea, Air, and Land (SEAL) forces, but it also incorporates Special Warfare Combatant Craft (SWCC) and other communities who commonly work with conventional and non-con­ventional forces.” Although the unit’s emphasis is on support of Naval Special Warfare operations, NOSWC can and regularly supports all types of special operations, throughout the globe. While a small component of METOC, personnel of the NOSWC have direct access to all of the other components of Naval Meteorology and Oceanography Command.
While the tools, techniques, and capabilities have changed over the decades from its incep­tion—many of which could never have been imag­ined in 1830—the spirit exemplified by Maury and other pioneers of Navy meteorology, oceanogra­phy, and navigation continues to drive those of METOC today; it is an enduring Pathfinder ethos.  
Part I of “U.S. Naval Oceanography: Pathfinders of the American Military” was pub­lished in the January/February 2023 issue of Weatherwise Magazine.
* Weatherwise contributing editor ED DARACK is an indepen­dent author and photographer based in Wyoming. Learn more at


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