into the Global Command and Communications
System-Maritime (GCCS-M), which was discussed in
chapter one. Information describing the status of all
GFMPL environmental programs and software
versions is contained in the Geophysics Fleet Mission
Program Library (GFMPL) Summary, also published
by NAVO. Both the NT and PC versions of GFMPL are
released as either unclassified or classified CD-ROMs.
The classified GFMPL CD-ROMs contain detailed
electromagnetic and acoustic models and data bases.
GFMPL is a rapid-response, on-scene,
environmental prediction system used to quickly
determine the effects of the environment on fleet
platforms, sensors, and weapon systems. Locally
collected environmental information is used to prepare
analyses of present atmospheric and electromagnetic
(EM) propagation conditions. Locally collected
oceanographic information is combined with archived
data to prepare an analysis of existing oceanographic
and acoustic conditions. Analyses and predictions are
based upon on-scene data, historical data, platform
characteristics, and weapon/sensor characteristics.
GFMPL comprises four basic functions as described
Environmental Data Assimilation
GFMPL accepts locally acquired environmental
data from various sources, catalogs and processes the
data, and then writes the data to available files for use by
the various programs. This data includes operator-
entered surface, radiosonde, refractivity,
bathythermograph, and nearshore bathymetry data.
This function also incorporates quality control checks
of environmental data input.
GFMPL generates analyses of existing
environmental conditions affecting air, surface,
amphibious, and USW operations. These analyses are
provided by atmospheric, meteorological, and
oceanographic application programs. The analyzed
data is presented in the form of graphic and tabular
displays, which can also be hardcopied and used for
performance predictions and briefings.
Sensor Detection Range/Coverage Prediction
GFMPL computes acoustic and electromagnetic
(EM) sensor range predictions based on oceanographic
and meteorological environmental profiles. Output is
used for detection/counter detection of threat/force
platforms. Platform and sensor data base parameters
can be modified as necessary (both acoustic and
atmospheric). Output is provided in either spreadsheet,
graphical, or tabular format.
Data File Maintenance
This function provides the capability to create,
maintain, and/or delete data files. This function also
ensures the integrity of the data files and provides
adequate safeguards for any classified information in
There are numerous environmental software
programs available from GFMPL, and each version
comes loaded with a different suite of programs. The
environmental programs provided with GFMPL NT
can be divided into seven broad categories, which are
EnvironmentThis option contains general
programs, such as Historical Electromagnetic
Propagation Conditions (HEPC) and Propagation
Conditions Summary (PCS). It also contains an ocean
Sound Speed Profile (SSP) program.
MeteorologyThis option contains programs
that calculate pressure altitude and density altitude data,
wind chill and heat stress values, and astronomical data
(sunrise, lunar illumination, civil twilight, etc.).
ElectromagneticsThis option contains
programs that predict radar performance and calculate
radar ranges. Electromagnetic programs include
surface-search radar range predictions and electronic
Electromagnetic path-loss curves and radar coverage
diagrams can also be produced.
OceanographyThis option contains programs
such as the Tidal Prediction and Analysis (TIDES), Surf
Forecasting (SURF), and Beach Survey Chart (BSC).
The BSC program allows for the creation, display, and
editing of a digital beach chart as surveyed by Special
AcousticThe Acoustic option contains the
Generic Acoustic Prediction (GAP) program and the
Tactical Oceanographic/Acoustic Spreadsheet (TOAS)
program. GAP is used to produce horizontal contours
of ocean temperature, sound speed, and salinity. It also