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Lidar Surveys. Jim Churnside NOAA Research. What is a lidar?. Operates like an echosounder , except with a short laser pulse instead of a short acoustic pulse. Operates from a small aircraft instead of a surface vessel.
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Lidar Surveys Jim Churnside NOAA Research
What is a lidar? • Operates like an echosounder, except with a short laser pulse instead of a short acoustic pulse. • Operates from a small aircraft instead of a surface vessel. • Penetrates to over 50 m in clear water, 20-30 m in murky coastal water.
Two Installations Piper Seminole NOAA Twin Otter
Intercomparisons • Intercomparisons have been made with acoustic and trawl surveys • Species include sardine, anchovy, herring, capelin, mackerel, and mixed schools (“baitfish”) • Correlations are high if lidar and surface surveys are close together (within about four days)
Plus Camera (or Video) • Images increase swath width, but with limited depth penetration • Images help to identify surface returns • Lidar helps to identify image features • Camera generally not useful at night (exception is low-light-level camera when bioluminescence is present)
Aircraft flight tracks 20 flights Nov. 3 – Dec. 10, 2010 26 hours, day 21 hours, night 10 000 km (San Diego to Beijing) 818 schools
Proposed Surveys • Coast-wide summer survey • Fall southern California survey • Either should be coordinated with a surface survey.
Hake Survey Survey example 2005 hake survey lines spaced by 10 nmi and extended from coastline to 50 m water depth. US portion accomplished with about two months of ship time at 11-12 kts (15,000 nmi). Aerial coverage would require about 100 hours
Budget • Coast-wide survey - $400K, including $140K aircraft costs, $250K labor and overheads (based on day and night coverage equivalent to two months of ship survey) • Southern California Survey - $115K, including $35K aircraft costs, $75K labor and overheads (based on day and night coverage of CalCOFI +) • These are total costs.
Questions • What is the best mix of ship and aircraft time to estimate sardine abundance and distribution? • Do we need to oversample with both in order to answer the first question?
Research Vessel Cost R/V New Horizon is intermediate class at $20,000 per day, or $1,200,000 for 60 days Does not include scientific personnel.
Survey Salary • GS-12, step 5, San Diego - $40 per hour • 24% benefits + 88% overhead - $85 per hour • 12 hour day – $1000 per day • 2 scientists for 60 days - $120,000 • Scientific staff of 12 for 60 days - $720,000