1 / 30

Why We Care

Why We Care. or Why We Go to Sea. Who Uses the Data?. Shipboard personnel Vessel operations Ocean deployments (buoys, CTDs, towed instruments) Science during cruise Secondary users (not on cruise) Ocean and atmosphere modelers Satellite (and other remote) measurement community

toan
Download Presentation

Why We Care

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Why We Care orWhy We Go to Sea

  2. Who Uses the Data? • Shipboard personnel • Vessel operations • Ocean deployments (buoys, CTDs, towed instruments) • Science during cruise • Secondary users (not on cruise) • Ocean and atmosphere modelers • Satellite (and other remote) measurement community • Air-sea interaction researchers • Product developers (climate atlases, gridded fields) • Instrument developers

  3. Satellite Algorithm Development Courtesy Darren Jackson, CIRES, NOAA/ESRL

  4. Satellite Validation • Research vessel observations provide an independent assessment of biases in marine observations made by Earth-orbiting satellites (and other remote sensing platforms)

  5. Ocean Model Verification Ship vs. Model Ship track over model salinity

  6. Air-Sea Flux Parameterization

  7. Real-Time Forecast ValidationData QC http://catalog1.eol.ucar.edu/cgi-bin/dynamo/research/date_browse?dateUTC=20111116

  8. Where does the data go? 2007-1999 (28 cruises)

  9. How to Measure • Know what you want to measure…..parameter(s) • Know Temporal and Spatial scales • Know sensor characteristics • Accuracy, Precision, Range, …… • Know the data acquisition system • Know the environment you will be working in

  10. What to Measure • Meteorology • Wind directions and speed • Air temperature • Humidity • Pressure • Rainfall • Radiation • Oceanography • Sea temperature • Salinity • Navigation • Latitude and longitude • Course over ground • Speed over ground • Speed relative to water • Heading

  11. Time Scales

  12. Time Scales

  13. Time Scales monthly weekly …. daily

  14. Sampling Rates The Nyquist-Shannon sampling theorem in general states a signal can be reconstructed from its samples if the sampling frequency is greater than twice the highest frequency of the signal: also known as the Nyquist frequency. • Oversampling is often preferred as it: • Can aid in anti-aliasing • Can be used to increase resolution when using A/D convertors • Can also help reduce uncorrelated noise when averaging multiple samples.

  15. Accuracy / Precision Targets

  16. Accuracy/Precision

  17. An Introduction to Marine Meteorology How does the Marine Environment differ from that over land? Homogeneity Moisture source Surface friction Diurnal cycles

  18. Surface Pressure • Pressure decreases with increasing height above the surface • ~0.1 mb m-1 near the surface • At a given location, pressure varies slowly • Typical range is 990-1030 mb away from strong storms • A diurnal atmospheric tide exists with a range of ±3 mb in the tropics http://volney-bodley-weather-project.wikispaces.com/

  19. Balloon Temperature, Humidity, and Winds % C ms-1

  20. Balloon Temperature, Humidity, and Winds RH Dir Speed Temp

  21. Precipitation/Clouds Radar reflectivity 24 hr Accumulated Rain

  22. Satellite Water Vapor 24 Oct 06Z

  23. Precipitation/Clouds Time (UTC) Total Precip 1.3 to 5.6 mm

  24. Precipitation

  25. Temperature Air Rain Rate

  26. Sea Temperature Local Time

  27. Sea Temperature

  28. Radiation • Downwelling shortwave radiation • Most common measurement on a research vessel • Value ~1000 Wm-2 on clear day at low latitude • Short-term variations commonly identify passing clouds (or other shadows). • Downwelling longwave (infrared) radiation • Emitted by clouds and atmospheric gases • In tropics, ranges from 350-400 Wm-2

  29. Radiation SW LW

  30. EndLesson One

More Related