NPOESS:
Dave Jones and Craig Nelson
This is the fifth in a series
of articles on the National Polar-orbiting Operational
Environmental Satellite System (NPOESS). As a critical
component of an Integrated Earth Observation System,
NPOESS will continuously monitor and observe land, sea,
and air to help “take the pulse of Planet Earth.”
Introduction: Global
Disasters–Local Consequences
Each year weather and climate related natural
hazards cause thousands of fatalities and tens of billions
of dollars in economic losses worldwide. Hurricanes,
typhoons, and mid-latitude storms often cause significant
loss of property and life. In 1970, a particularly intense
tropical cyclone killed at least 300,000 people in
Bangladesh. In 1992, Hurricane Andrew caused 26 deaths and
property losses of approximately $26.5 billion. In the
wake of Hurricane Charley that made landfall near
Charlotte Harbor Florida on August 13, 2004, emergency
management officials and damage assessors have directly
linked at least 16 deaths to the storm and estimate
property losses of $7 billion to $8 billion in insured
damage. Statistics compiled from insurance companies from
1950-1999 show that major natural catastrophes across the
globe caused economic losses of nearly $1 trillion.
At the other extreme, extended periods of
drought can be equally devastating. In 1988, dry
conditions in the Midwest caused an estimated $40 billion
in crop damage. Current drought conditions in the
southwest United States are seriously depleting water
resources in the Colorado and Rio Grande River basins,
impacting agriculture as well as interstate and
international relations. On a broader front, severe
drought, inadequate harvests, and civil war in Sudan are
putting hundreds of thousands of people at risk of
starvation. While these geographically separate conditions
affect people locally, worldwide conditions may be related
globally to the combined effects of climate change and El
Niño and La Niña events.
Environmental observing systems that support better
warnings and preparedness can reduce the loss of life and
property due to severe storms or drought.
Global Environmental Monitoring
In situ (“in place”) observing systems are
effective for local and regional monitoring and for
certain measurements for which remote sensing techniques
are not well suited. However, the global expanse and often
remote locations of natural hazards and climate change
effects require observing platforms that can provide
continuous global coverage.
Operational and research polar-orbiting satellites,
along with geostationary satellites, provide
cost-effective, continuous global coverage of critical
environmental information, such as storms, pollutants,
ocean surface temperatures, precipitation, soil moisture,
snow and ice cover, and vegetation health. Dr. Richard A.
Anthes, President of the University Corporation for
Atmospheric Research (UCAR), considers satellite
observations to be the “backbone of an Integrated Earth
Observation System.” Later this decade, NPOESS will take
its place as a series of Earth observation platforms.
With NPOESS satellites in three orbits,
equally-spaced in time, most locations on Earth will be
imaged and profiled every four hours or less to provide
real-time data, products, and information on a wide
variety of parameters, such as: ocean surface temperatures
and winds; ocean color; land surface temperatures;
terrestrial vegetation, land cover characteristics, and
change; soil moisture; atmospheric temperature and
humidity; snow cover; Arctic ice packs; and Antarctic ice
shelves. These sustained measurements will assist in
essential tasks, such as: improving weather forecasts,
assessing disasters, monitoring crops and climate,
managing marine resources, and determining environmental
change.
Polar-orbiting and geostationary satellite data
(GOES) already comprise over 99 percent of the data used
in numerical weather prediction (NWP) models (National
Centers for Environmental Prediction [NCEP]). NPOESS and
GOES-R (Aug-Sept issue) will begin to build the Global
Earth Observation System as envisioned by Vice Admiral
Conrad C. Lautenbacher, Ph.D., the Undersecretary of
Commerce for Oceans and Atmosphere and NOAA Administrator,
and the representatives from 49 other countries who have
agreed to participate in the project. According to VADM
Lautenbacher, a global network of observing systems
consisting of satellites, aircraft, and other ground- and
ocean-based platforms will allow scientists to take
“regular full-body scans of the Earth.”
These “Earth scans” will provide critical input
to numerical weather prediction models. In addition, these
scans will provide excellent input to those who predict
energy needs months in advance, anticipate soil moisture
conditions, and rainfall to help farmers decide what crops
to plant and where, to monitor forest fires and issue
timely warnings of poor air quality and to anticipate
outbreaks of environment-related diseases. It is expected
that the return on federal government investments in
NPOESS and GOES-R will be enormous and continue to benefit
the nation and international community for decades to
come.
Data Management
To meet the challenges of archiving and
distributing data from the next generation of
environmental satellite systems, NOAA is developing the
Comprehensive Large Array-data Stewardship System (CLASS).
CLASS will enhance NOAA’s capabilities to provide
environmental data and information archive and access
services both nationally and internationally through
effective application of modern, adaptable data storage
and distribution technologies. CLASS will be focused on
efficient archival of vast quantities of satellite and in
situ observations, permanent and secure storage, and
rapid, cost- effective access to the data. It is
anticipated that these goals will be achieved through
increased data storage capacity; improved computer power;
use of commercially available, modular hardware and
software; enhanced communications capabilities; and
improved access through the World Wide Web using enhanced
database management tools for search, browse, subset, and
order functions.
NOAA and NASA are collaborating so lessons learned
can be applied from NASA’s past work designing the
EOSDIS data system, which primarily serves the science
research community. NOAA’s challenge is to better serve
a large number of growing user communities with
operational and research needs.
Ocean Remote Sensing
For the 71 percent of the Earth covered by water,
space-based remote sensing provides the only means of
obtaining synoptic views of the world’s oceans and their
surface processes at high spatial resolution over time
periods ranging from hours and days to weeks and years.
Ocean observations comprise approximately
one-fourth of the 55 requirements for geophysical
measurements that will be made by NPOESS sensors. These
requirements were established based primarily on existing
capabilities and current uses of remote sensing data for
applications such as maritime weather warnings, sea ice
mapping, ship routing, monitoring of biological
productivity zones, harmful algal bloom detection,
fisheries management, and climate change analysis.
However, many ocean observations from NPOESS and other
observing systems will be used to protect, restore, and
manage the use of coastal and ocean resources. Users also
projected needs for higher resolution satellite data to
support operations in coastal and open ocean regions.
Although NPOESS will carry only one instrument
designed specifically for ocean observations (i.e., a
Radar Altimeter), ocean requirements have directly and
substantially “driven” the design and acquisition for
the VIIRS and CMIS instruments. With these instruments,
NPOESS will deliver higher resolution (spatial and
temporal) and more accurate measurements of: sea surface
temperature (SST), ocean surface
wind vectors/stress, ocean color, suspended matter, and
derived parameters, such as harmful algal blooms, sea ice
(edge motion, age, surface temperature, thickness);
oceanic heat flux, significant wave height, and sea
surface topography. Coastal change will also be an
important product from NPOESS as more and more people move
to the coastline. Barrier islands move and change, they
are dynamic systems that can be monitored from space.
Natural Hazards Monitoring
New sensors are yielding valuable information for
the early detection and tracking of developing tropical
depressions that often grow into tropical storms and
hurricanes. Recent studies by scientists at NOAA’s
Atlantic Oceanographic and Meteorological (AOML)
Laboratory have demonstrated that in some cases the closed
circulation in surface winds of a developing tropical
depression can be detected in observations of ocean
surface wind speed and direction from the SeaWinds
scatterometer on NASA’s QuikSCAT satellite, prior to
seeing cloud swirls in the more traditional visible and
infrared satellite imagery. According to Dr. Kristina
Katsaros, former Director of AOML, “with more precise
input about ocean surface wind speed [and direction],
models [will] have more precise information that [may]
lead to more accurate predictions of a hurricane’s
evolution and course.” The CMIS instrument on NPOESS
will provide the operational capability for observing
ocean surface wind speed and direction that will be an
important addition to the other tools available to the
tropical cyclone forecasting community. Data from CMIS
will help improve detection and tracking of developing
tropical cyclones in their earliest stages, far from land
and surface ship observations where satellites provide the
primary source of information on these storms. Near
hurricane landfall, precipitation, and soil moisture
measurements from CMIS, may also yield critical
information for emergency managers in areas susceptible to
flooding and mudslides.
While forecasts of hurricane landfall and intensity
have improved over the years, there is room for
improvement. Data from the atmospheric sounders (ATMS and
CrIS) on NPP and NPOESS will be used to generate vertical
cross-sections through hurricanes to derive quantitative
information on the warm core and intensity of storms. And,
multiple sensors on NPOESS (i.e., VIIRS, CMIS, ATMS, and
CrIS) will allow forecasters to more accurately diagnose
hurricane intensity and thereby improve numerical model
predictions for hurricane tracks, landfall, and intensity.
From land to sea, to wind, rain and drought,
improved global monitoring of the Earth will benefit the
world’s people and provide valuable information about
our dynamic and changing environment. This added knowledge
from NPOESS and other future satellite systems combined
should help to lessen the impact of those changes. NPOESS
will be an important step in making that a reality.
Higher (spatial, temporal, and spectral) resolution
and more accurate sounding data from instruments on NPOESS,
with greater aerial coverage, will also provide the
necessary increase in data resolution in order to support
continuing advances in numerical weather prediction models
to improve short- to medium-range weather forecasts. We
will dive in further and explore just how NPOESS will
contribute to improved numerical weather prediction in our
next article.
About the Authors:
Dave Jones is Founder, President and CEO of
StormCenter Communications, Inc. (stormcenter.com).
He is also President of the Foundation for Earth Science
and sits on the Executive Committee of the ESIP Federation
(esipfed.org).
Craig Nelson is the former Executive Director of
the NPOESS Integrated Program Office (IPO). He is employed
by General Dynamics Advanced Information Systems as a
support contractor to the IPO and can be reached at [email protected].
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