Presentation is loading. Please wait.

Presentation is loading. Please wait.

Tracking an Atlantic Wave Storm with Jason-2 Altimeter Sérgio Muacho - IPMA.

Similar presentations


Presentation on theme: "Tracking an Atlantic Wave Storm with Jason-2 Altimeter Sérgio Muacho - IPMA."— Presentation transcript:

1 Tracking an Atlantic Wave Storm with Jason-2 Altimeter Sérgio Muacho - IPMA

2 Tracking an Atlantic Wave Storm with Jason-2 Altimeter - Operational oceanography (waves and wind) - Mean Sea Level - Tides - Ocean large-scale circulation - Ocean currents and eddies - Bathymetry - Tsunamis Altimetry applications for oceans and seas:

3 Tracking an Atlantic Wave Storm with Jason-2 Altimeter - Operational oceanography (waves and wind) - Mean Sea Level - Tides - Ocean large-scale circulation - Ocean currents and eddies - Bathymetry - Tsunamis Altimetry applications for oceans and seas: here we will focus on…

4 Tracking an Atlantic Wave Storm with Jason-2 Altimeter Do you know other applications of altimetry?Yes No

5 Tracking an Atlantic Wave Storm with Jason-2 Altimeter Do you know other applications of altimetry?Yes No - Ice (Ice sheets; Sea ice) - Climate (ENSO; NAO; Decadal oscillations) - Atmosphere (Cyclones; Rain) - Hydrology & land (Lake level; River level)

6 Tracking an Atlantic Wave Storm with Jason-2 Altimeter Chapter I: Introduction Jason-2 radar

7 Tracking an Atlantic Wave Storm with Jason-2 Altimeter -Satellite does not measure individual waves… - Satellite beam is about 1-2 km minimum in diameter; - Measurements are averaged (over 1s, ~7km along the track) to remove noise. Some considerations about altimetry:

8 Tracking an Atlantic Wave Storm with Jason-2 Altimeter The radar altimeter receives the reflected wave (echo), which varies in intensity over time. If sea surface is flat (a), the reflected wave's amplitude increases sharply from the moment the leading edge of the radar signal strikes the surface. In rough seas (b), the wave strikes the crest of one wave and then a series of other crests which cause the reflected wave's amplitude to increase more gradually. * We can derive ocean wave height from the information in this reflected wave: the slope of the curve representing its amplitude over time is proportional to wave height. * from Satellite Radar wave Radar wave as seen from above the surface Shape of the power as received back by the onboard radar

9 Tracking an Atlantic Wave Storm with Jason-2 Altimeter How do satellite altimeters measure ocean waves?

10 Tracking an Atlantic Wave Storm with Jason-2 Altimeter - Over ocean surface, the echo waveform has a characteristic shape that can be described analytically (Brown model); - The edge slope is related to the significant wave height (SWH) time power How do satellite altimeters measure ocean waves?

11 Tracking an Atlantic Wave Storm with Jason-2 Altimeter

12 This is an ascending or descending orbit? Ascending Descending

13 Tracking an Atlantic Wave Storm with Jason-2 Altimeter Can we use altimetry data in an operation way? Yes No

14 Tracking an Atlantic Wave Storm with Jason-2 Altimeter No, because the satellite goes over the same point every cycle (10 days at least, up to 35 days depending on the satellite) Can we use altimetry data in an operation way? Yes No

15 Tracking an Atlantic Wave Storm with Jason-2 Altimeter In my opinion, yes…! If a satellite goes over your region of interest (ROI), you can have data 2 hours after the measurements. This is relevant in oceans and sea zones with a lack of observations (buoys), such as West Iberian coast and more off-shore areas. Can we use altimetry data in an operation way? Yes No

16 Tracking an Atlantic Wave Storm with Jason-2 Altimeter The Atlantic wave storm (17 – 20 April 2012)

17 Wave storm life cycle: The early stages (synoptic conditions) Plot: surface wind >10 m/s Azores Tracking an Atlantic Wave Storm with Jason-2 Altimeter

18 Wave storm life cycle: The early stages (synoptic conditions) Plot: surface wind >10 m/s Azores Steady southwesterly flow with several cyclogenesis, some of them originate deep lows with very strong winds Tracking an Atlantic Wave Storm with Jason-2 Altimeter

19 Azores Omega Block between 14 and 20th april 2012 with some minor changes in position B B A Tracking an Atlantic Wave Storm with Jason-2 Altimeter Wave storm life cycle: The early stages (synoptic conditions)

20 Wave storm generation and propagation Adapted for Tracking an Atlantic Wave Storm with Jason-2 Altimeter

21 Wave storm propagation (03UTC 17 April-12): model results (WAM/ECMWF) and Jason-2 Tracking an Atlantic Wave Storm with Jason-2 Altimeter

22 Wave storm propagation (17 and 18 Apr 2012): model results (WAM/ECMWF) Tracking an Atlantic Wave Storm with Jason-2 Altimeter

23 Approaching shore in Bay of Biscay and West Iberian coast (19 and 20 Apr 2012): model results (WAM/ECMWF) Tracking an Atlantic Wave Storm with Jason-2 Altimeter

24 Let’s track the storm… with Jason-2! Tracking an Atlantic Wave Storm with Jason-2 Altimeter

25 Jason-2 data and wave model forecast (03 UTC 17-Apr) Tracking an Atlantic Wave Storm with Jason-2 Altimeter

26 Jason-2 data and wave model forecast (03 UTC 17-Apr) Tracking an Atlantic Wave Storm with Jason-2 Altimeter

27 Jason-2 data and wave model forecast (03 UTC 18-Apr)

28 Tracking an Atlantic Wave Storm with Jason-2 Altimeter Jason-2 data and wave model forecast (03 UTC 18-Apr)

29 Tracking an Atlantic Wave Storm with Jason-2 Altimeter Jason-2 data and wave model forecast (18 UTC 18-Apr)

30 Tracking an Atlantic Wave Storm with Jason-2 Altimeter Jason-2 data and wave model forecast (21 UTC 18-Apr)

31 Tracking an Atlantic Wave Storm with Jason-2 Altimeter Jason-2 data and wave model forecast (06 UTC 19-Apr)

32 Tracking an Atlantic Wave Storm with Jason-2 Altimeter Important ideas: We collect 5 passages during a three days period (17, 18 and 19 April 2012) in our ROI; Jason-2 data is in good agreement with wave model and buoys (~2400 points with a mean difference of 3,5cm); We can use altimetry information to supply the lack of buoys in off-shore areas (we can monitor sea conditions!).

33 Tracking an Atlantic Wave Storm with Jason-2 Altimeter Important ideas: We collect 5 passages during a three days period (17, 18 and 19 April 2012) in our ROI; Jason-2 data is in good agreement with wave model and buoys (~2400 points with a mean difference of 3,5cm); We can use altimetry information to supply the lack of buoys in off-shore areas (we can monitor sea conditions!). But…. It is difficult to track a storm only with the altimetry data: Altimetry doesn’t give you an idea of sea conditions in all your ROI; Miss important information for marine forecasters, such as wave direction.

34 Jason-2 data against buoys data in West Iberian coast Tracking an Atlantic Wave Storm with Jason-2 Altimeter

35 Jason-2 data and wave model forecast (03 UTC 18-Apr) º

36 º ~1,4m 02h45m, 18-Apr Tracking an Atlantic Wave Storm with Jason-2 Altimeter Jason-2 data against buoys data

37 Tracking an Atlantic Wave Storm with Jason-2 Altimeter Jason-2 data and wave model forecast (18 UTC 18-Apr) º

38 Jason-2 data against buoys data º ~7,8m 17h17m, 18-Apr Tracking an Atlantic Wave Storm with Jason-2 Altimeter

39 Additional issues:

40 Tracking an Atlantic Wave Storm with Jason-2 Altimeter Jason-2 near costal regions (e.g., NW Iberian coast)

41 Tracking an Atlantic Wave Storm with Jason-2 Altimeter Jason-2 near islands (e.g., Azores) North swell: Wave refraction is well represented by altimetry

42 Tracking an Atlantic Wave Storm with Jason-2 Altimeter Update – Atlantic ePort !

43 Tracking an Atlantic Wave Storm with Jason-2 Altimeter Atlantic ePort (http://eumetrain.org) Archive: 10 April 2012 onwards

44 Portuguese Hydrographical Institute (www.hidrografico.pt)www.hidrografico.pt Spanish Hydrographical Institute (www.puertos.es)www.puertos.es Tracking an Atlantic Wave Storm with Jason-2 Altimeter Acknowledges

45 Tracking an Atlantic Wave Storm with Jason-2 Altimeter - Thank you! -


Download ppt "Tracking an Atlantic Wave Storm with Jason-2 Altimeter Sérgio Muacho - IPMA."

Similar presentations


Ads by Google