# 1 Introduction

## 1.1 Why is More Hurricane R&D Needed?

The revolution in the accuracy and utility of weather forecasts that has
occurred in the past several decades has improved forecasts and warnings
for tropical cyclones. The last decade has brought major advances in
observing systems (figure 1-1), computing technology, numerical modeling
and data assimilation, and the scientific understanding of the physics
that underlie various types of weather phenomena, including tropical
cyclones.

![](media/image1.jpeg){width="4.114566929133859in"
height="3.75in"}Nevertheless, further improvements to the Nation's
tropical cyclone forecast and warning service are feasible, within
reach, and *valuable investments for our safety, security, and economic
well-being*. Whether called "hurricanes" (in the North Atlantic and in
the Pacific off the coasts of the Americas), "typhoons (in the Pacific
west of the International Date Line), or other regional appellations,
these severe cyclonic storms are causing increasing amounts of
destruction, death, and injury primarily due to the increasing
population density and economic infrastructure of coastal regions. Fifty
percent of Americans now live within 50 miles of a coastline; 90 percent
live within 200 miles of the coast and are thus potentially exposed to
the wrath of a landfalling hurricane.

Vulnerability of the U.S. mainland to damage from tropical cyclones has
increased primarily because of the growth in population (4.5 percent per
year) and wealth along the U. S. coast from Texas to Maine. In a recent
analysis of hurricane damages from 1900 to 2005, Pielke et al. (2007)
noted that their normalization method agrees with insurance industry
data in projecting a doubling of economic losses from landfalling
hurricanes every ten years. Vulnerability of U.S. overseas interests
reflects increased military presence in regions of high tropical cyclone
activity. One important contribution to avoiding loss of lives and
reducing vulnerability to hurricane landfall and tropical cyclone
movement is highly accurate meteorological forecasts that can be used to
ensure that credible warnings are issued in a timely manner. In
addition, the public and military operations being threatened must have
confidence in those warnings, understand them, and take the appropriate
actions to protect property and evacuate when necessary.

![](media/image2.png){width="4.25in" height="2.525196850393701in"}The
2005 hurricane season in the North Atlantic and Caribbean region set
records for damage to the U.S. mainland. On July 10, 2005, Hurricane
Dennis made landfall near Pensacola, Florida, with 105-kt winds and
10-foot storm surges. Florida residents were not strangers to
hurricanes, as this was the fifth hurricane to hit Florida in less than
a year. On August 25, 2005, Hurricane Katrina killed 14 in southeastern
Florida when it brought heavy rains and winds to that region. On August
29--30, Katrina blasted the Louisiana and Mississippi coasts, coming
onshore just east of New Orleans (figure 1-2). Katrina's winds and
massive flooding left thousands homeless, 2.3 million without
electricity, roads and bridges destroyed, and communications inoperable.
The storm surge caused by Katrina swamped the Mississippi Gulf Coast,
destroying hundreds of homes, roads, and much of the coastal
infrastructure. In Hurricane Katrina's wake, the estimated direct
fatalities were 1,353,[^1] making it the third deadliest hurricane in
the United States. Not only did Katrina cause a large death toll, it
also caused approximately \$100 billion in losses.

Hurricane Rita, which struck the Florida Keys and the Gulf Coast in
September after Katrina, is described below. Then, from October 18 to
24, Hurricane Wilma ravaged Haiti, Jamaica, Cozumel, Cancun, Playa del
Carmen, and eventually southern Florida. At one point, Wilma
strengthened to category 5 on the Saffir-Simpson intensity scale for
tropical cyclones (table 1-1), and on October 19 it became the deepest
(lowest pressure) hurricane on record in the Atlantic, with a pressure
dropping to 882 millibars. Wilma was the fourth storm in the 2005 season
to reach category 5.

The Saffir-Simpson hurricane scale is a rating from 1 to 5, based on a
tropical cyclone\'s present intensity. Wind speed is the determining
factor in the scale, as storm surge values are highly dependent on the
slope of the continental shelf and the shape of the coastline in the
landfall region. The Saffir-Simpson category provides an estimate of the
potential property damage and flooding expected along the coast from a
hurricane landfall.

**Table 1-1.** Saffir-Simpson Hurricane Scale

  ---------- ------------ ------------- ----------- ----------------------------
  Category   Sustained    Barometric    Storm       Potential Property Damage
             Wind^a^      Pressure      Surge\      
                          (millibars)   (feet above 
                                        normal)     

  1          74--95 mph\  \>980         4--4        No real damage to building
             (65--8n                                structures. Damage primarily
             knts)                                  to unanchored mobile homes,
                                                    shrubbery, and trees. Also,
                                                    some coastal flooding and
                                                    minor pier damage.

  2          96--110 mph\ 965--979      6--8        Some roofing material, door,
             (83--95 knt)                           and window damage of
                                                    buildings. Considerable
                                                    damage to vegetation, mobile
                                                    homes, etc. Flooding damages
                                                    piers and small craft in
                                                    unprotected anchorages break
                                                    moorings.

  3          111--130     945--964      9--12       Some structural damage to
             mph\                                   small residences and utility
             (96--113                               buildings with a minor
             knt)                                   amount of curtainwall
                                                    failures. Mobile homes are
                                                    destroyed. Flooding near the
                                                    coast destroys small
                                                    structures with larger
                                                    structures damaged by
                                                    floating debris. Terrain may
                                                    be flooded well inland.

  4          131--155     920--944      13--18      More extensive curtainwall
             mph\                                   failures with some complete
             (114--135                              roof structure failure on
             knt)                                   small residences. Major
                                                    erosion of beach areas.
                                                    Terrain may be flooded well
                                                    inland.

  5          \>155 mph\   \<920         \>18        Complete roof failure on
             (\>135 knt)                            many residences and
                                                    industrial buildings. Some
                                                    complete building failures
                                                    with small utility buildings
                                                    blown over or away. Flooding
                                                    causes major damage to lower
                                                    floors of all structures
                                                    near the shoreline. Massive
                                                    evacuation of residential
                                                    areas may be required.
  ---------- ------------ ------------- ----------- ----------------------------

^a^ Wind speed, measured as the one-minute average at 10 m elevation,
determines the intensity category.

The four case studies of recent severe storms presented below illustrate
both the current status of tropical cyclone forecasting and warning and
some of the challenges for doing better. These current capabilities and
their limitations are documented systematically in chapter 3. The
limitations and a prioritized list of operational needs defined by the
national operational forecast and warning centers are used in chapters
4, 5, and 6 to derive a set of research priorities and to propose the
next steps by which the national research and development (R&D)
community---including Federal agency, academic, and industry
partners---can work together to meet the challenges posed by tropical
cyclones.

## 1.2 Tropical Cyclone Forecasts and Warnings: Recent Cases

Three of the four storms described here were hurricanes that made
destructive landfalls in the contiguous United States (CONUS). They were
tracked by the Tropical Prediction Center's National Hurricane Center
(TPC/NHC), an arm of the National Oceanic and Atmospheric Administration
(NOAA) in the Department of Commerce (DOC). The fourth was a super
typhoon tracked by the Joint Typhoon Warning Center (JTWC), whose
primary mission within the Department of Defense (DOD) is to support
U.S. military operations and protect defense assets threatened by
tropical cyclones in its area of responsibility. Section 1.3 describes
the areas of responsibility and roles of each of the U.S. operational
centers for tropical cyclone forecasting and warning, along with
supporting roles played by the principal elements of the national R&D
community.

### 1.2.1 Hurricane Floyd, September 1999

![](media/image3.jpeg){width="3.25in"
height="2.6251968503937007in"}Hurricane Floyd pounded the central and
northern Bahama Islands, seriously threatened Florida, struck the North
Carolina coast, and moved up the United States east coast into New
England (figure 1-3). Floyd's center paralleled the central Florida
coast, passing about 95 miles east of Cape Canaveral on September 15. On
September 13, as Floyd neared the Bahamas, it reached its peak intensity
of 135 knots---at the top end of category four on the Saffir-Simpson
scale. After striking Eleuthera and Abaco Islands in the Bahamas on
September 14, Floyd weakened but was still a borderline category
three/four hurricane. A gradual turn to the right resulted in the track
parallel to the Florida coast. On the afternoon of the September 15th,
Floyd was near the Florida/Georgia border and moved northward toward the
Carolinas. The eyewall structure was diminishing as Floyd made landfall
near Cape Fear, North Carolina, early on September 16. Storm surge
values up to 9--10 feet were reported along the North Carolina Coast.
Weakening to a tropical storm and accelerating in forward speed, Floyd
interacted with a preexisting frontal zone along the Atlantic seaboard,
bringing heavy rains that set one-day records in several locations from
North Carolina and Virginia to portions of New England. Of the 57 deaths
attributed to Floyd, 56 were in the United States. Most were due to
drowning in freshwater flooding. Insured losses totaled \$1.325 billion,
with total damage estimates ranging from \$3 billion to \$6 billion
(Pasch et al. 1999).

The TPC/NHC began tracking Floyd on September 2 with satellite imagery
of a tropical wave emerging from western Africa. Satellite images in the
visible, infrared, and microwave bands provided the evidence to name the
growing system Tropical Storm Floyd on September 8, while it was still
750 nmi east of the Leeward Islands. In its Tropical Cyclone Report for
Hurricane Floyd, the TPC/NHC noted that, averaged over the entire
lifetime of the storm, the track forecasts were excellent. However,
during the crucial period when Floyd was approaching the U.S. mainland
and hurricane warnings were in effect, the official track forecasts and
the objective guidance models had a westward and slow bias relative to
the best track from observations. Also, the official forecasts did not
capture all of the weakening in intensity that occurred after the storm
peaked over the Bahamas. From September 13 onward, the maximum sustained
wind speed was overpredicted by as much as 30 to 40 knots (Pasch et al.
1999).

As Floyd moved toward central Florida, the forecast track indicated
potential for the western eyewall to reach the coastline. Local forecast
products and information sent to emergency managers indicated a
likelihood of category one hurricane conditions, but they also stressed
that a small deviation west of the expected track could bring category
three winds to the coast. Based on Floyd's strength, the large radius of
maximum winds, and the uncertainties in Floyd's forecast track and
intensity, local officials ordered a massive coastal evacuation (Kelly,
Bragaw, and Spratt 1999). More than 2 million people in Florida
evacuated. Floyd's turn to the north, pulled by a mid-latitude trough,
in fact came early enough that only hurricane-strength wind gusts and
severe beach erosion occurred along the Florida coast. With improved
track and intensity forecasts, such massive evacuations can be tuned and
timed more closely to affect just the communities at risk.

### 1.2.2 Super Typhoon 04W (Typhoon Ewiniar), July 2006

An example from the western North Pacific of circumstances where more
accurate tropical cyclone forecasts are needed occurred in July 2006.
This intense cyclone, locally named Typhoon Ewiniar, severely disrupted
military operations in the East China Sea and the Sea of Japan.
Forecasts issued by the JTWC called for Ewiniar to move over Sasebo,
Japan, where many U. S. military vessels are stationed. Figure 1-4 shows
the forecasted track issued at 1200 UTC on July 5. In view of these
forecasts, ships were sortied (sailed) from Sasebo eastward into the
open Pacific Ocean. To execute the sortie, large amounts of shipyard
personnel time were expended to ready the ships and move them out to
sea. Furthermore, these movements away from their normal stations had a
substantial negative impact on the warfighting capability of the U. S.
military in the region for the duration of the sortie activity.

As can be seen in the final storm track in figure 1-5, Typhoon Ewiniar
in fact took a more westerly track, making landfall on the southwestern
coast of South Korea. Preliminary post analysis indicates that more
accurate forecasts, including improved NWP models, would have led to
less drastic disruptions, saving money by not moving ships from their
port and allowing key U. S. military assets to maintain an uninterrupted
readiness posture.

Tropical cyclones like Typhoon Ewiniar and the Atlantic hurricanes
impact military operations in every basin. Costs to sortie ships and
aircraft can run into the millions each year as decision-makers work to
keep assets protected while continuing national security missions. The
costs for Hurricane Katrina alone are still being calculated for units
along the Gulf Coast that were
![](media/image4.png){width="6.026377952755905in"
height="3.7992125984251968in"}impacted and units that participated in
rescue and clean up missions. Ships and aircraft routinely operate
around tropical cyclones in the northwest Pacific, where the military
services incur substantial costs to divert ships or relocate aircraft to
keep national security missions on track. Even so, the cost to sortie or
divert is far less than the cost to replace an aircraft or ship caught
unprepared by a storm-strength tropical cyclone.

![](media/image5.png){width="3.2283464566929134in"
height="3.0956692913385826in"}

Tropical cyclones in the western Pacific differ in some respects from
Atlantic basin and East Pacific storms. Typhoons, as tropical cyclones
are called in that region, are generally more frequent, more intense,
and have a large range of sizes from "midget" to "monster" storms. Each
tropical cyclone season in the northwest Pacific alone yields at least
four super typhoons. Differences arise largely because these storms
often evolve in a more complex web of dynamical processes and physical
nonlinear interactions, including feedback loops associated with the
Asian Monsoon and imbedded disturbances. Also, tropical cyclone research
and operations in the western Pacific are handicapped relative to the
Atlantic by a lesser observational data base, especially the lack of
aircraft surveillance and reconnaissance. (See section 3.1 for an
assessment of aircraft surveillance and reconnaissance capabilities.)

### 1.2.3 Hurricane Dennis, July 2005

Two of the hurricanes from the record 2005 Atlantic season provide
additional examples of ways in which improved forecasts and warnings for
tropical cyclones could better prepare the at-risk population. The first
of these is the storm surge associated with Hurricane Dennis. Dennis
made landfall on Santa Rosa Island, Florida, between Navarre Beach and
Gulf Breeze, on July 10, 2005. The maximum sustained winds at landfall
were 105 kt. Dennis produced a storm surge of 6-7 feet above normal tide
levels on Santa Rosa Island, near where the center made landfall. This
surge overwashed Santa Rosa Island near and west of Navarre Beach. A
storm surge of 6-9 feet above normal tide levels occurred in Apalachee
Bay, Florida, and inundated parts of the town of St. Marks and nearby
areas.

This surge was higher than was supported by the wind reports known for
that area prior to landfall. It was roughly 3.5 feet higher than the
surge forecast from the Sea, Lake, and Overland Surge from Hurricanes
(SLOSH) model. The likely explanation is that the unexpected surge was
triggered by a sea-rise wave that became trapped on the oceanic shelf
along the Florida west coast and propagated northward (Beven 2005). As
an Associated Press article said of the impact on the St. Marks area:
"This small fishing village on the picturesque St. Marks River received
a nasty surprise from Hurricane Dennis: Although it came ashore some 175
miles west, Dennis pushed an 8-foot storm surge down the mouth of the
river, flooding businesses and homes with chest-deep water" (Kallestad
2005). Long-time residents were "all in one piece" and happy to survive
the storm surge associated with Hurricane Dennis.

### ![](media/image6.jpeg){width="3.3751968503937007in" height="3.3751968503937007in"}1.2.4 Hurricane Rita, September 2005

The second example from the 2005 Atlantic hurricane season is Hurricane
Rita, which struck in September 2005 after Katrina. On 20 September
2005, Hurricane Rita dumped heavy rains on the Florida Keys. It reached
category 5 strength over the central Gulf of Mexico but eventually
weakened prior to making landfall as a category 3 hurricane at Sabine
Pass near the Texas-Louisiana border (figure 1-6). The strong storm
surge and heavy winds caused major damage in the Louisiana and Texas
coastal areas.

As stated in the TPC/NHC Tropical Cyclone Report for Hurricane Rita
(Knabb et al. 2006):

> *Official forecasts issued on 20-21 September, however, were more
> biased to the south and were late in forecasting Rita's turn toward
> the northwest. Then, on 22--23 September, official forecasts within
> about 48 h of final landfall were once again quite accurate, except
> for incorrectly antici­pating Rita to stall within a couple of days
> after moving inland (as did all of the reliable models).*

This southern bias, which called for landfall near Galveston, Texas,
with effects of the storm also forecast to impact the greater Houston
area, is clearly seen in the TPC/NHC's best track positions for
Hurricane Rita (figure 1-7) compared to the TPC/NHC advisory #10, issued
at 5 a.m. EDT, Tuesday, September 20, 2005 (figure 1-8). Given the track
and storm surge predicted for Rita, the mayor of Galveston ordered
mandatory evacuations of nursing homes and assisted-living facilities
starting at 6 a.m. Wednesday, September 21. The mayor also ordered
mandatory evacuations of other parts of the city to begin at 6 p.m. that
day. In Houston, a similar scene unfolded, as the mayor of Houston
ordered evacuations. In all, more than 1.3 million residents of Texas
and Louisiana were ordered to evacuate and seek safety from Hurricane
Rita. Highways leading out of Houston quickly became gridlocked up to
100 miles north of the city. Again, in hindsight, not all the
evacuations ordered were necessary.

## 1.3 The Need for Hurricane R&D Priorities and Coordination

![](media/image7.png){width="2.9173228346456694in"
height="2.338188976377953in"}![](media/image8.jpeg){width="3.0in"
height="2.333464566929134in"}As portrayed above, tropical cyclones can
have catastrophic impacts, which make accurate predictions of these
events of paramount importance. There is no doubt that skill in tropical
cyclone track forecasting has improved significantly during recent
decades. Emergency management and other end-user responses to these
improved forecasts and warnings result in lives saved, as well as
reduction of property damage, physical injuries, and psychological
distress. For example, in a typical hurricane season, forecasts,
warnings, and associated emergency responses are estimated to save \$3
billion (Willoughby 2001).

Even with these savings, more must be done to improve the Nation's
hurricane and typhoon forecast and warning capability. A high priority
for further tropical cyclone research is to reduce the uncertainty and
forecast bias (the difference between forecast and actual conditions) in
storm track, intensity, and the factors that drive them, to provide
targeted warnings and emergency preparations, and to ensure that
populations and locations at risk receive timely and reliable
information. There are still serious forecast challenges, especially in
support of the emergency management needs of growing coastal populations
that are vulnerable to loss of life, property damage, and socioeconomic
hardships caused by tropical cyclones. In addition, the DOD operates in
environments around the world where tropical cyclones occur regularly.
These national security missions must continue, and lives and assets
must be protected. Military decision makers must allocate limited
resources to both protect and complete the missions.

In addition to physical sciences research that must continue to meet
these forecast challenges, greater emphasis is needed on social science
research. A growing need exists to connect improved tropical cyclone
forecasts and warnings to response actions, thereby ensuring the most
appropriate responses by decision makers, by those who implement the
decisions, and by the entire at-risk population. One such research area
is how different end-users of tropical cyclone forecasts and warnings
receive, interpret, and act on that information. Because this and many
other questions in improving the effectiveness of warnings and emergency
response and preparedness require research in the social sciences, this
plan includes social science research recommendations.

## 1.4 Operational Tropical Cyclone Forecast and Warning Centers

The purpose of this plan is to guide the next decade of tropical cyclone
research efforts, justifying them through their linkages to the
operational needs of the Nation's tropical cyclone warning service. A
major part of the effort in formulating the plan was a compilation and
assessment of these operational needs.

The tropical cyclone warning service is an interdepartmental effort to
provide the United States and designated international recipients with
forecasts, warnings, and assessments concerning tropical and subtropical
weather systems. The three centers that cooperate to provide this
service are discussed below. Figure 1-9 shows the areas of
responsibility for tropical cyclone forecasts and warnings for the
TPC/NHC, the Central Pacific Hurricane Center (CPHC), and the JTWC.

### 1.4.1 Tropical Prediction Center/National Hurricane Center

The TPC is one of the twelve centers comprising the National Centers for
Environmental Prediction (NCEP), a component of the NOAA National
Weather Service (NOAA/NWS). Located at Florida International University
in Miami, Florida, the TPC is the Regional Specialized Meteorological
Center (RSMC) designated by the World Meteorological Organization (WMO)
for the northeast Atlantic Ocean, including the Caribbean and Gulf of
Mexico, and the northeast Pacific Ocean east of longitude 140º W. The
TPC provides general weather guidance, as well as specialized products
for aviation and marine interests in the tropics. Both the TPC/NHC and
the CPHC take their mission direction from the National Hurricane
Operations Plan.

![](media/image9.jpeg){width="6.3125984251968505in"
height="4.733858267716536in"} The TPC consists of three major
components:

-   The **National Hurricane Center** (NHC) maintains a continuous watch
    on tropical cyclones from May 15 in the northeastern Pacific and
    June 1 in the north Atlantic through November 30. The Center
    prepares and issues forecasts, watches, and warnings for its area of
    responsibility, as well as text advisories and graphical products.
    During the off-season, the NHC conducts an extensive outreach and
    education program to train U.S. emergency managers and
    representatives from many other countries affected by tropical
    cyclones.

-   The **Technical Support Branch** (TSB) provides support for TPC
    computer and communications systems. The TSB also maintains a small
    applied research and techniques development unit that develops tools
    for hurricane and tropical weather analysis and prediction. TSB also
    has a storm surge group that provides support for the SLOSH model,
    which is used to calculate storm surge.

-   The **Tropical Analysis and Forecast Branch** (TAFB) provides
    year-round marine weather analysis and forecast products over the
    tropical and subtropical waters of the eastern North and South
    Pacific and the North Atlantic basin. The branch also produces
    satellite-based weather interpretation and rainfall estimates for
    the international community. The TAFB provides support to NHC
    through manpower augmentations and tropical cyclone position and
    intensity estimates based on the Dvorak technique.

***The remainder of this document will refer to the TPC as a whole using
the standard abbreviation TPC/NHC.*** The TPC/NHC also contains the
Chief, Aerial Reconnaissance Coordination, All Hurricanes (CARCAH) unit.
This three person unit is an Operating Location of the 53^rd^ Weather
Reconnaissance Squadron (Hurricane Hunters) out of Keesler Air Force
Base near Biloxi, Mississippi. CARCAH\'s mission is to coordinate all
aerial reconnaissance requirements at TPC/NHC (Atlantic requirements)
and at the Central Pacific Hurricane Center (Central Pacific
requirements), and then task the flying units to meet these
requirements.

### 1.4.2 Joint Typhoon Warning Center

![](media/image10.jpeg){width="3.6251968503937007in"
height="2.91259842519685in"}The JTWC (figure 1-10) is a joint Air
Force/Navy tropical cyclone forecasting center. Located at Naval Base
Pearl Harbor, Hawaii, the JTWC is the DOD agency responsible for issuing
tropical cyclone warnings for the Pacific and Indian Oceans. JTWC
support encompasses more than 110 million square miles of the north and
south Pacific Ocean and Indian Ocean, reaching from the west coast of
the Americas to the east coast of Africa. The JTWC takes its mission
direction from the Commander, US Pacific Command Instruction 3140.1w
(version 1w is the latest in the series). In addition to the
watch-standing operations floor, the JTWC houses the Satellite
Operations Flight, charged with conducting all activities related to the
satellite reconnaissance used in the tropical cyclone warning process.
The JTWC also has a Techniques Development element that operationally
evaluates forecast processes and transitions them to the watch floor
operations. Both elements interface with the research and development
community to evaluate tropical cyclone research and its utility for
fast-paced military oper--ations support. A substantial amount of the
JTWC\'s numerical model computer support comes from the Fleet Numerical
Meteorology and Oceanography Center (FNMOC) at Monterey, California.

### 1.4.3 Central Pacific Hurricane Center

CPHC has forecast and warning responsibility for the central North
Pacific from 140º W longitude to the International Date Line. The CPHC
is a component of the NOAA/NWS Weather Service Forecast Office (WFO),
Honolulu, Hawaii (figure 1-11). The Meteorologist-In-Charge, WFO
Honolulu, is also the Director of the CPHC. Because the WFO Honolulu has
no authorized manpower for the specialized hurricane operations of the
CPHC, the center is activated only when a tropical cyclone crosses into
the area between 140º W longitude and the International Date Line. On
July 1, 2001, the WFO Honolulu was designated a WMO RSMC. Most outside
support, such as model and techniques development and aerial
reconnaissance, is provided through the same infrastructure that
supports the TPC/NHC.

### ![](media/image11.jpeg){width="3.104330708661417in" height="1.802755905511811in"}![](media/image12.jpeg){width="3.104330708661417in" height="1.816535433070866in"}1.4.4 Supporting Role of Other NOAA/NCEP Operational Centers

Other NCEP centers have specific responsibilities dealing with
forecasting the conditions and consequences of tropical cyclones. A
substantial amount of TPC/NHC's numerical modeling computer support
comes from NCEP's Environmental Modeling Center (EMC). The
Hydrometeorological Prediction Center (HPC) issues forecasts of inland
flooding caused by tropical cyclone rains. The Storm Prediction Center
(SPC) provides forecasts and watches for severe thunderstorms and
tornadoes. At sea, the Ocean Prediction Center (OPC) provides forecasts
to mariners that incorporate TPC/NHC official tropical cyclone
forecasts.

## 1.5 Introduction to the Tropical Cyclone R&D Community

While the tropical cyclone operational forecast and warning centers are
few in number and have clearly defined roles and geographic areas of
responsibility, numerous entities in the public and private sector,
including the academic community, contribute to tropical cyclone
research. To formulate a national plan for coordinating these research
efforts with the needs of the operational centers, it is useful to view
these decentralized, distributed research activities, in conjunction
with the operational centers, as forming a *community of practice*.
Chapter 2 examines the major R&D centers and other players in light of
their interactions. This section provides a short introduction to the
community of practice.

The tropical cyclone community of practice has grown through statutory
encouragement of collaborative R&D activities. In the NOAA Authorization
Act of 1992 (Public Law 102-567), Section 107, Congress mandated that
the DOD and the DOC establish a joint hurricane reconnaissance program
"for collecting operational and reconnaissance data, conducting
research, and analyzing data on tropical cyclones to assist the forecast
and warning program and increase the understanding of the causes and
behavior of tropical cyclones." In January 1994, the initial 5-year plan
outlining this shared responsibility was forwarded to Congress. In
addition to NOAA (in the DOC) and DOD, numerous national and
international universities and several other Federal agencies,
laboratories, and organizations conduct tropical cyclone research.

### 1.5.1 Federal R&D Organizations

Federal R&D in the physical sciences either specific to understanding
and predicting tropical cyclone behavior or relevant to it is conducted
within or overseen by the NOAA in the DOC, the National Science
Foundation (NSF), the Office of Naval Research (ONR) and the U.S. Army
Corps of Engineers (USACE) in DOD, the National Aeronautics and Space
Administration (NASA), and the U.S. Geological Survey (USGS) in the
Department of the Interior. The work within each of these entities is
described briefly below and in more detail in section 2.2.

In addition, R&D related to emergency preparedness for and response to
tropical cyclones is conducted or overseen by the Federal Emergency
Management Agency (FEMA) in the Department of Homeland Security and by
the Office of Policy Development and Research (PD&R) in the Department
of Housing and Urban Development (HUD). The Department of Health and
Human Services conducts some relevant research on the psychological
stresses resulting from major hurricane strikes. The National Institute
of Standards and Technology (NIST), through its Building and Fire
Research Laboratory, conducts research on facility construction that
includes reducing the human and economic losses from natural hazards
such as tropical cyclones. The R&D roles of these entities are described
in section 2.3.

#### National Oceanic and Atmospheric Administration

The majority of research within NOAA specific to understanding and
predicting tropical cyclone behavior is conducted or managed by the
Hurricane Research Division (HRD) of the Atlantic Oceanographic and
Meteorological Laboratory (AOML), a facility within the NOAA Office of
Atmospheric Research (OAR). Within NOAA's NWS, research specific to or
related to tropical cyclones is conducted by the Storm Prediction Center
(one of the NCEP centers), some of the WFOs, and the CPHC. The Center
for Satellite Applications and Research (STAR), which is part of NOAA's
National Environmental Satellite, Data, and Information Service
(NESDIS), conducts a tropical cyclone research program that emphasizes
satellite-based observations. STAR is the Federal partner from NESDIS in
the Joint Center for Satellite Data Assimilation (JCSDA).

#### National Science Foundation

The NSF is the funding source for about 20 percent of all federally
supported basic research conducted by U.S. colleges and universities.
The physical, biological, and ecological aspects of NSF's
hurricane-related research are managed through its Geosciences
Directorate (GEO) and Biological Sciences Directorate (BIO).
Hurricane-related engineering research is supported through various
programs within the Directorate for Engineering (ENG).

A number of major academic research centers with tropical cyclone
programs and research projects receive a substantial part of their
funding from the NSF, through grants managed by these NSF directorates.
See sections 1.5.2 and 2.5 for further information on these centers and
their role in the tropical cyclone community of practice.

#### Department of Defense

Within ONR, the Ocean Atmosphere & Space Research division has a Marine
Meteorology and Atmospheric Effects program, whose topics of interest
include problems of predictability, data assimilation into models, and
tropical cyclone evolution and behavior. The Naval Research Laboratory
(NRL) is the Navy's corporate laboratory and is aligned with ONR. Within
NRL, the directorate most directly involved in tropical cyclone research
is the Ocean and Atmospheric Science and Technology Directorate.

#### National Aeronautics and Space Administration

NASA contributions to tropical cyclone R&D are primarily in the area of
developing instrumentation for and interpreting the data from
satellite-based observing systems. A mandate of NASA's Science Mission
Directorate is to investigate high-impact weather events, including
severe tropical storms, through a combination of spaced-based
observations, high-altitude research aircraft, and sophisticated
numerical models. NASA investigations in these areas constitute a
three-pronged strategy to better understand the physics and impacts of
tropical cyclones.

#### U.S. Geological Survey

The USGS is working with NOAA and NASA to improve understanding and
prediction of floods, landslides, and debris flows triggered by intense
meteorological phenomena, including the heavy rains typical of
landfalling tropical cyclones. The mechanism to integrate the research
efforts underway in each of the three agencies is the proposed
Hurricane-Flood-Landslide Continuum Project. The USGS components include
precipitation-runoff modeling of watershed systems. These computer
models are used to simulate and evaluate the effects of various
combinations of precipitation, climate, and land use on stream flow,
sediment yield, and other hydrologic components.

### 1.5.2 Academic Partners in Tropical Cyclone R&D

The National Center for Atmospheric Research (NCAR), located in Boulder,
Colorado, is a federally funded research and development center operated
by the University Corporation for Atmospheric Research (UCAR). UCAR is a
nonprofit consortium of North American member universities, each of
which grants doctoral degrees in the atmospheric and related sciences,
plus an increasing number of international affiliates offering
comparable degrees, and North American academic affiliates offering
predoctoral degrees. NSF is the primary sponsor for NCAR, but it also
receives funding from NOAA, NASA, DOD, the Department of Energy, the
Federal Aviation Administration, and the U.S. Environmental Protection
Agency. Working with multiple agency sponsors, NCAR and collaborators
are investigating ways to improve forecasts of changes in hurricane
intensity and prediction of wind, waves, and rain at landfall.

Other academic R&D active centers in research on tropical cyclone
observing and forecast methods are the University of
Wisconsin-Cooperative Institute for Meteorological Satellite Studies
(UW-CIMSS) and the Cooperative Institute for Research in the Atmosphere
(CIRA), an R&D center at Colorado State University. Academic centers
engaged in related research include the Cooperative Institute for
Oceanographic Satellite Studies (CIOSS) at Oregon State University and
the Cooperative Institute for Climate Studies (CICS) at University of
Maryland.

In general, Federal agencies that sponsor *extramural research* programs
on tropical cyclone evolution and behavior, societal impacts of
hurricanes and related severe weather phenomena, or satellite-based
observations of relevant atmospheric and oceanic properties provide
funding to university-based researchers. The research projects may be
part of an ongoing program at one of the major academic centers such as
NCAR, CIMSS, or CIRA, or they may be conducted by an individual
principal investigator (PI) on the faculty of a college or university.

### 1.5.3 Coordination Roles in the Tropical Cyclone Community of Practice

With multiple Federal entities funding R&D directed at a broad array of
topics related to the tropical cyclone life cycle, observing systems,
computer modeling for storm prediction and warning, and the consequences
of tropical storms on both land and sea, coordination of these separate
programs is essential to ensuring the most productive overall return,
over the long term, for the substantial investment of taxpayer dollars.
Section 2.4 provides further details on the coordinating entities and
mechanisms listed here:

-   The mission of the **Office of the Federal Coordinator for
    Meteorological Services and Supporting Research** (OFCM), located
    within NOAA, is to ensure the effective use of Federal
    meteorological resources by leading the systematic coordination of
    operational weather requirements, services, and supporting research
    among the Federal agencies. The focus of OFCM coordination is on
    applied research necessary to meet operational needs and the
    effective transition of results from such research into operations.
    OFCM hosts the annual **Interdepartmental Hurricane Conferences**,
    which provide a forum for the Federal agencies with operational and
    R&D responsibilities related to tropical cyclones, together with
    emergency managers and other representatives of the agencies' user
    communities, to review the Nation's tropical cyclone forecast and
    warning service and make recommendations on how to improve it.

-   The **Office of Science and Technology Policy** (OSTP) works with
    the Office of Management and Budget (OMB) to provide all Federal
    agencies with general guidance on national priorities for R&D
    programs. The Director of OSTP manages the **National Science and
    Technology Council** (NSTC) for the President. This Cabinet-level
    council prepares R&D strategies that are coordinated across Federal
    agencies to form investment packages aimed at accomplishing multiple
    national goals.

    -   One of the four primary committees of the NSTC is the
        **Committee on Environment and Natural Resources** (CENR), whose
        **Subcommittee on Disaster Reduction** (SDR) is the NSTC entity
        most closely related to coordination of tropical cyclone R&D
        across agency boundaries.

    -   Another standing subcommittee of the CENR is the **United States
        Group on Earth Observations** (US GEO), which is continuing the
        strategic planning and implementation for the U.S. Integrated
        Earth Observation System (IEOS). IEOS represents the U.S.
        contribution to the Global Earth Observing System of Systems
        (GEOSS), an international effort to achieve comprehensive,
        coordinated, and sustained observations of the Earth system.

-   The **National Science Board** (NSB) provides national science
    policy advice to the President and serves as the governing board for
    NSF.

-   The **U.S. Weather Research Program** (USWRP) is a partnership of
    Federal entities with the academic and commercial communities. NOAA,
    NASA, NSF, and the Navy currently participate. In 1998, the fifth
    Prospectus Development Team for the USWRP published "Landfalling
    Tropical Cyclones: Forecast Problems and Associated Research
    Opportunities" (Marks and Shay 1998). NOAA subsequently requested
    funding, as part of its Natural Disaster Reduction Initiative, to
    support the USWRP priorities for improving the forecast accuracy and
    lead-time for hurricane landfall location using state-of-the art
    instruments deployed from NOAA aircraft during coordinated hurricane
    surveillance missions.

-   The **Joint Center for Satellite Data Assimilation** (JCSDA) was
    formed by NOAA, NASA, and DOD in 2001 to expedite the process of
    assimilating data from new satellite-based observing systems and
    instruments into operational models used to prepare forecasts and
    warnings. As illustrated in section 1.2, advances in satellite-based
    imagery and observing techniques have been a major contributor to
    recent improvements in forecasts and warnings for tropical cyclones.

### 1.5.4 Other Participants in the R&D Community

The community of practice for tropical cyclone R&D and operations
includes international participants. Other nations that are vulnerable
to the damaging effects of tropical cyclones include Japan, China,
Taiwan, Korea, and Australia. The national meteorological agencies in
these countries typically have a closely allied research center or
institute that contributes to the global effort to understand tropical
cyclones and improve operational forecast and warning capabilities.
International cooperation and coordination includes both the broad
strategic planning effort of GEOSS and a number of important joint
experimental activities such as the Pacific Asian Regional Campaign of
the [TH]{.underline}e [O]{.underline}bserving system
[R]{.underline}esearch and [P]{.underline}redictability
[EX]{.underline}periment (THORPEX). The main objective of this regional
THORPEX campaign is to advance the understanding and predictability of
high-impact weather over Asia and the western Pacific, with emphasis on
tropical cyclones from genesis to their decay or transition to
extratropical status.

Also important to the U.S. community of practice are nongovernmental
bodies representing the professional scientific community. The National
Academy of Sciences (NAS) and its operational component for conducting
studies, the National Research Council (NRC), have Congressional
charters to advise the U.S. Government. The American Meteorological
Society Policy Program has as its national priorities public health and
safety, economic growth, the protection of the environment, and national
security. Both bodies play important roles in communicating consensus
perspectives from the scientific community to decision makers in the
Federal policy and coordinating entities noted in section 1.5.3, as well
as in the Federal agencies with operational responsibilities or R&D
programs.

## 1.6 Formation of the JAG/TCR

The impetus for this Tropical Cyclone R&D Plan was a principal action
item, agreed upon by the participants in the 58^th^ Interdepartmental
Hurricane Conference (IHC) in 2004, to develop a comprehensive strategy
for tropical cyclone research and development to guide interagency
efforts over the next decade. (As noted above, OFCM hosts an IHC each
year.) Subsequently, the Interdepartmental Committee for Meteorological
Services and Supporting Research (ICMSSR) strongly supported this action
at its November 2004 meeting. To implement the action, the Federal
Coordinator for Meteorology formed the Joint Action Group for Tropical
Cyclone Research (JAG/TCR) in early 2005. During the group's first
meeting, members developed a rough outline for this plan and agreed to
compile previous research plans and efforts into one reference location.
The outcome of these efforts was the development of a Reference Report
Webpage, <http://www.ofcm.gov/tcr/tcr-index.htm>.

The vision of the JAG/TCR was to maximize the potential of the tropical
cyclone community partnerships to improve hurricane prediction,
preparedness, and resiliency for societal benefit by strategically
matching research results to operational requirements. The JAG/TCR
members agreed that past research planning efforts clearly outlined the
tropical cyclone community's priorities, objectives, and strategies, as
developed and vetted through many meetings and workshops. These
significant past efforts are reviewed in section 2.8.

## 1.7 Structure of the R&D Plan

This introductory chapter illustrates the fundamental rationale for
continuing efforts to further advance tropical cyclone forecasts and
warnings. It introduces the operational centers for the Nation's
tropical cyclone warning service, serving both civilian and military
needs, and the community of practice that supports these operational
centers.

Chapter 2 describes in more detail the community of practice.
Understanding how this community works---its strengths and its
limitations---is crucial for formulating and implementing a
community-wide, comprehensive strategy for tropical cyclone R&D that can
guide interagency efforts over the next decade. Chapter 2 also reviews
recent and concurrent planning activities that were taken into account
in formulating the research priorities.

Chapter 3 assesses the current capabilities and limitations of the
Nation's tropical cyclone warning service. These capabilities constitute
a classic end-to-end meteorological warning and forecasting system, from
data collection through data assimilation and NWP modeling, to
dissemination of warnings and forecasts, including end-user education,
training, and outreach.

Chapter 4 uses the same end-to-end system structure to present the
JAG/TCR's perspective on the future capabilities required to meet both
current operational needs and emerging needs ***identified by the
operational centers**.* This perspective draws heavily on recent
significant research planning efforts and products, as well as on the
expertise of the JAG/TCR members collectively and of the R&D and
operational organizations they represent. In Chapter 5, these future
capabilities are translated into a set of research priorities, around
which a comprehensive R&D strategy for the next decade can be built.
Chapter 6 presents a summary of key findings and the JAG/TCR
recommendations for next steps that can be taken by the cognizant
Federal agencies and coordinating entities to begin implementation of
this strategy.

Literature references for the citations in the report body and the
appendices are in the References section after chapter 5. Appendices A
through K provide backup information on the current operational
capabilities reviewed in chapter 3.

-   Appendix A---Satellite data currently used in NCEP's operational
    data assimilation systems

-   Appendix B---Impact on tropical cyclone forecast skill of
    improvements in global prediction models and operational
    high-resolution regional models

-   Appendix C---Research NWP models relevant to improvements in
    tropical cyclone prediction

-   Appendix D---Forecasts and models currently in use at the TPC/NHC
    and CPHC

-   Appendix E---Forecasts and models currently in use at the JTWC

-   Appendix F---Guidance model errors in tropical cyclone storm track
    during 2005

-   Appendix G---Guidance model errors in tropical cyclone intensity
    during 2005

-   Appendix H---Example of recent public education and outreach through
    an article in NOAA's online *NOAA Magazine*

The remaining appendices provide supporting details for chapters 4
through 6.

-   Appendix I---Satellite observations to be assimilated at NCEP as new
    observing instruments come on line

-   Appendix J---MetOp Satellite Data Pertinent to Tropical Cyclone
    Analysis and Forecasting

-   Appendix K---Recent developments in data assimilation for NWP
    modeling

-   Appendix L---NCEP plan for development of improved global NWP models

-   Appendix M---Future work planned for the HWRF Air-Sea-Land-Hurricane
    Prediction System

-   Appendix N---Questions from the Air-Sea Interactions in Tropical
    Cyclones Workshop

-   Appendix P---The JAG/TCR's recommended research areas for tropical
    cyclone--related social science R&D

-   Appendix Q---Acronyms used in the report body and the appendices

[^1]: This estimate as of May 15, 2006, is based on information from
    affected states' departments of health. The estimate includes direct
    fatalities only and does not include out-of-state evacuee fatalities
    included in some calculations. Fatalities by state: Louisiana 1,097;
    Mississippi 238; Florida 14, Alabama 2; and Georgia 2.