1. Satellite Oceanography Presented at STAO 2003 Dr. Michael J. Passow White Plains Middle School, White Plains, NY, Science Teachers Association of New York State (STANYS), and Amer. Meteorological Society Education Resource Agent

2. Ocean Satellites Permit observations globally, especially useful where no ships or buoys Developed later than meteorological and other environmental sensing because electromagnetic radiation penetrates ocean water only to limited depths Improved sensors permit inferences about ocean at greater depths

3. "Satellite Oceanography" Sensors aboard satellites provide global views and allow temporal (time) studies not possible from surface vessels. Surface topography, El Nino, and ocean winds are some of the areas being investi- gated from space. http://winds.jpl.nasa.gov/

4. Satellite Oceanography Applications Sea surface temperatures Air-sea interactions Sea Ice patterns Monitoring ocean waves Determining sea level variations Analysis of ocean currents and eddies Biological productivity Precipitation patterns

5. Problem 1— How do you get a satellite into orbit? Basically, a rocket is a chamber with an opening containing gas under pressure. A balloon can serve as a simple model. As the gas escapes, its thrust in one direction propels the rocket in the opposite direction. http://quest.arc.nasa.gov/space/teachers/rockets/principles.html

6. What keeps an object in orbit? Satellites can only stay in orbit when the gravitational pull exactly balances the forward motion (inertia). These ideas were first explained by Newton in the 1680s! http://quest.arc.nasa.gov/space/teachers/rockets/principles.html

7. Two basic satellite orbits “Polar Orbiting” (POES) Takes about 90 minutes to make one revolution Covers different areas each orbit as Earth rotates Provides detailed images Can produce time sequence Geostationary (Geosynchronous) (GOES) Remains over same portion of planet by revolving with same period as Earth’s rotation Can provide full disk or smaller views Useful for weather and communication

8. http://www.iitap.iastate.edu/gcp/satellite/images/image7.gif

9. For more detailed studies, we use “polar-orbiting” satellites Polar-orbiting satellites are much closer to the surface (700 – 800 km) and make about 14 passes each day. They can provide good time sequence studies. http://www.earth.nasa.gov/history/landsat/landsat4.html

10. Satellites can detect what’s on Earth in two ways: “passive” observation of energy reflected or radiated from the surface “active” collection of signals beamed down from the satellite and reflected back http://topex-www.jpl.nasa.gov/ Problem 2— How do you measure from a satellite?

11. Sea surface temperatures (SST) and thermal properties Visible satellites can monitor difference between incoming solar radiation and reflected light Infrared satellites can monitor IR energy emitted from surfaces AVHRR (Advanced Very High Resolution Radiometer) measure SSTs Also monitored with MODIS (Moderate Resolution Imaging Spectroradiometer)

12. SST Images [link through DStreme Ocean] http://www.cdc.noaa.gov/map/images/sst/sst.gif

13. Sea Surface Temperature Anomalies (SSTA) Images constructed by measuring difference between “observed” and “expected” values – anomalies Better approach to recognizing “what is unusual,” not just “what is” Especially useful for El Nino/La Nina studies—example: http://orbit- net.nesdis.noaa.gov/orad/sub/sst_anomaly_2m.html http://orbit- net.nesdis.noaa.gov/orad/sub/sst_anomaly_2m.html

14. SSTA images http://www.osdpd.noaa.gov/PSB/EPS/SST/climo.html

15. Ocean Color – Biological Productivity http://seawifs.gsfc.nasa.gov/cgi/seawifs_browse.pl Sea-viewing Wide Field-of-View Sensor (SeaWIFS) and MODIS have measured chlorophyll in phytoplankton to enable useful inferences about productivity http://seawifs.gsfc.nasa.gov/cgi/seawifs_browse.pl

16. SeaWIFS has allowed us to monitor the links between physical and chemical conditions and marine biology Short-term spatial and temporal variabilities Biological response to climate changes http://seawifs.gsfc.nasa.gov/SEAWIFS.html

17. Sea Surface Topography Variations in sea surface heights caused by gravity variations (sea floor topography and geology) Also seasonal changes in atmospheric and ocean circulation patterns Radar altimeters aboard TOPEX/Poseidon and Jason satellites AMS “Measuring Sea Level from Space”

18. TOPEX-Poseidon is… a partnership between the U.S. and France to monitor global ocean circulation, discover the tie between the oceans and atmosphere, and improve global climate predictions. Every 10 days, the TOPEX/Poseidon satellite measures global sea level with unparalleled accuracy. http://topex-www.jpl.nasa.gov/mission/mission.html

19. TOPEX has been especially useful in understanding… Variations in sea surface temperatures. This has been the most important instrument for observing El Nino/ La Nina changes in the Pacific Ocean, and all the effects on climate http://topex-www.jpl.nasa.gov/elnino/elnino.html

20. Jason 1 is a follow-on mission to TOPEX- Poseidon Monitors global ocean circulation, studies ties between the oceans and atmosphere, improves global climate forecasts and predictions, and monitors events such as El Niño conditions and ocean eddies. http://www.jpl.nasa.gov/missions/current/jason1.html

21. Sea Ice Extent Areal extent, amount, and thickness important for oceanographers and operationally Visible images not feasible during winter POES microwave sensors provide operational ice analyses The next slide shows an example of sea ice cover in the Northern Hemisphere

22. http://polar.wwb.noaa.gov/seaice/Analyses.html

23. Precipitation Patterns Preponderance of precipitation falls in tropical regions Previously difficult to measure because few observation stations TRMM (Tropical Rainfall Measuring Mission) began as experimental, now operational

24. TRMM Precipitation Patterns http://trmm.gsfc.nasa.gov/ This shows average rainfall in the Tropics last month. Monthly records go back to 1998.

25. Precipitation Anomaly Patterns Anomaly images show regions of that are unusually higher or lower than normal. http://trmm.gsfc.nasa.gov/images/3B43_anom_oct03.gif

26. Hurricane and Lightning Images TRMM images have permitted amazing new views of storms and related weather in the Tropics. http://trmm.gsfc.nasa.gov/images_dir/images.html

27. Activities Based on TRMM Data Institute for Global Environmental Studies (IGES) http://www.strategies.org/TRMM.html Classroom-oriented activities based on TRMM concerning ENERGY, CLOUDS, WIND, PRECIPITATION, AND WEATHER

28. Canadian Satellite Imagery Meteorological Service of Canada (Service météorologique du Canada) provides many satellite images at http://www.weatheroffice.ec.gc.ca/satellite/index_e.html These utilize NOAA GOES and POES images.

29. http://www.weatheroffice.ec.gc.ca/satellite/index_e.html#hrpt

30. Canadian Sea Ice Imagery Ice conditions monitored by satellite and ships are available at http://ice- glaces.ec.gc.ca/App/WsvPageDsp.cfm?ID=1&Lang=eng http://ice- glaces.ec.gc.ca/App/WsvPageDsp.cfm?ID=1&Lang=eng

31. Examples of Teacher-Training and Classroom-Ready Activities AMS “Measuring Sea Level from Space” DataStreme Ocean investigations – modified from the Fall 2003 pilot testing

32. This slide show is available in the “Resources” Section of “Earth2Class” michael@earth2class.org