Introduction to CDIP
The Coastal Data Information Program (CDIP) is an extensive network for
monitoring waves and beaches along the coastlines of the United States.
Since its inception in
1975, the program has produced a vast database of publicly-accessible
environmental data for use by coastal engineers and planners, scientists,
mariners, and marine enthusiasts. The program has also remained at
the forefront of coastal monitoring, developing numerous innovations
in instrumentation, system control and management, computer hardware
and software, field equipment, and installation techniques.
CDIP is operated by the Ocean Engineering Research Group (OERG), part of
the Integrative Oceanography Division (IOD) at Scripps Institution
of Oceanography (SIO).
History and Funding
With seed money from the
California Sea Grant Program, Dr.
Richard J. Seymour and the OERG staff developed a wave data collection
system which could be accessed remotely by normal telephone lines.
Managed by David Castel, CDIP was joined in 1991 by Co-PI Dr. Robert Guza and
Associate PI Dr. William O'Reilly. Following his retirement in 2005, Julie
Thomas, a long time employee of the program took over the management
position. CDIP has grown
steadily over the years so that to date it has deployed and maintained wave
measuring stations at well over 100 locations in the western
hemisphere. The majority of these stations were deployed along the US
Pacific and Atlantic coasts, while others with some exceptions still
occupy locations in the Great Lakes,
Hawaiian Islands, Guam, Brazil, and the Gulf of Mexico.
At some locations, the wave data have been complemented by the
collection of other climatological parameters - temperature, winds and air
pressure. In all respects - from sensor reliability to the speed
of data distribution - CDIP has advanced significantly from its beginnings.
In the early years, most of the wave data were collected close to
shore using underwater pressure sensors which in turn were connected to
proximate land-based field stations via high density armored electrical
cables. At prescribed intervals, in response to querying phone calls from
CDIP's central computing facility, the remote stations would telemeter the
data over standard phone lines
to SIO where they would be quality controlled and analyzed in quasi real
time and archived for dissemination
to coastal engineers and others in
the oceanographic community via printed monthly and annual reports.
Not long after its inception in 1977, CDIP began to collect directional
wave data using arrays of underwater pressure sensors. Then, in 1978,
non-directional buoys came into use, allowing data collection from
locations further offshore. In the 1980s, use of all these instruments
was expanded to many new locations. It was in the 1990s, however, that
CDIP's operations underwent a wide range of changes.
In the 1990s CDIP first began to use directional buoys. These buoys,
which measure sea surface temperature and wave direction in addition
to wave energy, have become CDIP's primary instrument. By the late
1990s the nature of data acquisition increased
to the point that continuous data collection was achieved at a nominal one
Hz. sampling frequency. Equally
momentous, in 1996 the program started to make its data available
in real-time over the internet, including the highly popular swell models.
Today, all of CDIP's data and products are available on the web in
near real-time. Rapid dissemination of quality controlled data continues to
be a hallmark of the program.
Datawell buoys can be equipped with Iridium satellite communication
capabilities. CDIP is now in the
process of converting all of their buoys to make use of Iridium communications,
eliminating the need for shore stations and allowing for buoy deployments further
from the coastline. In the years
to come, CDIP will continue to strive to provide the most complete,
accurate, and timely collection of wave and climatological data
CDIP was established largely in response to a call for the development
of a nearshore wave climatology for the United States which would allow
coastal engineers and planners to make more rational design decisions.
This focus was intensified with the addition of the US Army Corps of
Engineers as a program sponsor. As the steward of the nation's coastal
infrastructure, the USACE requires reliable, long-term wave measurements
for use in planning, designing, and operating coastal projects. Fulfilling
this need remains a central aim of CDIP to this day, one that the group
takes very seriously. Waves are a critical factor in all shore
processes, playing a central role in everything from stresses on coastal
structures to sand transport and beach formation.
Wave data are also used in other research contexts, and CDIP strives to
provide data suitable for these areas of study as well. For instance,
laboratory and analytical research into the physics of wave
generation, propagation, and transformation requires field measurements
for calibration and verification. Similarly, studies of extreme events -
where coastal structures may be damaged, or nearshore activities
disrupted - rely heavily on accurate wave data sets.
CDIP's goals are not, however, limited to supplying the research
community with data. Another central focus of the group's work is
providing real-time wave data to a variety of users. Through the CDIP
website and in cooperation with NOAA's
National Weather Service and
Data Buoy Center,
the program's latest measurements are distributed to thousands of
users every 30 minutes. These users are both professional - harbor
masters, lifeguards, mariners, etc. - and recreational - boaters, surfers
and beach-goers. Through the widespread distribution of this information,
CDIP aims to promote public safety and the responsible use and enjoyment
of our coastal resources.
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