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NOAA NDBC vs CDIP Buoys

NOAA NDBC vs CDIP Buoys

Two major buoy networks provide wave data in the United States: NOAA's National Data Buoy Center (NDBC) and Scripps Institution's Coastal Data Information Program (CDIP). Understanding their differences helps you choose the best data for your needs.

NOAA NDBC (National Data Buoy Center)

Coverage: Nationwide and global Primary mission: Marine weather and safety Operated by: National Oceanic and Atmospheric Administration

Characteristics

  • Large network: 100+ buoys in US waters plus international stations
  • Offshore focus: Many buoys located far from shore (20-100+ miles)
  • Real-time data: Updated hourly
  • Free and public: All data freely available
  • Station IDs: Typically 5-digit codes (e.g., 46225, 41113)

What NDBC Measures

  • Wave height, period, and direction
  • Wind speed and direction
  • Air and water temperature
  • Barometric pressure
  • Some stations: spectral wave data

Best For

  • General offshore conditions
  • Marine weather forecasting
  • Shipping and boating safety
  • Wide geographic coverage
  • Long-term climate data

CDIP (Coastal Data Information Program)

Coverage: US West Coast, Hawaii, Great Lakes, some East Coast Primary mission: Coastal engineering and surf forecasting Operated by: Scripps Institution of Oceanography (UCSD)

Characteristics

  • Coastal focus: Many nearshore and pier-mounted sensors
  • High-quality spectral data: Detailed wave frequency analysis
  • Specialized deployment: Optimized for surf and coastal zones
  • Station IDs: 3-digit codes (e.g., 201, 143, 100)
  • Research-grade: Scientific accuracy for coastal studies

What CDIP Measures

  • High-resolution spectral wave data
  • Detailed directional wave information
  • Swell separation by frequency bands
  • Multiple swell components simultaneously

Best For

  • Surf forecasting (especially West Coast)
  • Nearshore wave conditions
  • Detailed swell analysis
  • Separating multiple swells
  • Coastal engineering projects

Key Differences

Location Strategy

NDBC: Offshore buoys capture open ocean conditions before swells reach shore. Great for advance warning and general trends.

CDIP: Nearshore sensors show what's actually hitting the beach. Better representation of local surf conditions.

Data Resolution

NDBC: Standard wave parameters (height, period, direction). Some stations provide spectral data.

CDIP: Comprehensive spectral analysis showing multiple swell components, frequencies, and directional spread.

Update Frequency

NDBC: Hourly updates CDIP: 30-minute updates (varies by station)

Geographic Coverage

NDBC: Nationwide and global CDIP: Concentrated in California, Hawaii, with expanding coverage elsewhere

Which Should You Use?

For Surf Forecasting

West Coast: CDIP preferred - better coastal coverage and nearshore data East Coast: Mix of both - CDIP where available (Florida, Carolinas), NDBC elsewhere Hawaii: CDIP strongly preferred - excellent coverage and surf-focused Gulf Coast: NDBC primary - limited CDIP presence

For Offshore Conditions

Always use NDBC - far more offshore buoys and global coverage

For Detailed Analysis

CDIP spectral data - separates multiple swells, identifies swell sources, advanced forecasting

For General Conditions

Either works - both provide reliable wave height, period, and direction

Dual-Source Stations

Some locations have both NDBC and CDIP buoys nearby. BuoyBoy shows when both sources are available, letting you:

  • Compare readings between offshore (NDBC) and nearshore (CDIP)
  • Track swell propagation from deep water to coast
  • Verify forecast accuracy using multiple data points
  • NDBC 46225 (Torrey Pines Outer) - offshore
  • CDIP 100 (Torrey Pines Outer) - same location, different network
  • CDIP 201 (Scripps Nearshore) - very close to shore

Data Attribution

When using these networks, remember:

NDBC: Data from NOAA's National Data Buoy Center CDIP: Data from CDIP, Scripps Institution of Oceanography

Both are publicly funded and provide free data - support their continued operation by proper attribution and advocacy for ocean monitoring programs.

Bottom Line

  • NDBC: Best for offshore, nationwide coverage, marine weather
  • CDIP: Best for surf, nearshore conditions, detailed spectral analysis
  • Use both when possible for complete picture of swell conditions

BuoyBoy integrates data from both networks, automatically selecting the best source for each station and showing when multiple sources are available.