Navigational sea ice analysis for the RV Xuelong in Prydz Bay, East Antarctica, 2011/12 to 2014/15

Transcription

1 Navigational sea ice analysis for the RV Xuelong in Prydz Bay, East Antarctica, 2011/12 to 2014/15 Xiao Cheng, Fengming Hui, Tiancheng Zhao, Xinqing Li, Yan Liu College of Global Change and Earth System Science, Beijing Normal University, China Petra Heil Australian Antarctic Division and Antarctic Climate and Ecosystems Cooperative Research Centre, University of Tasmania, Australia

2 Outline Introduction Data and methods Navigational analysis Discussions

3 1. Introduction Sea ice is sensitive to climate change, and also exerts significant impact on navigation and other maritime activities. Previous navigational studies in sea-ice regions resorted to use SAR data in the Arctic, especially for the Northern Sea Route and Canadian Archipelago. Recently the increase of Antarctic sea-ice extent and its regional variability have coincided with several maritime incidents. What data are required to maintain a sustained information flow on sea-ice conditions with relevance to ice navigation in Antarctica? The image was downloaded from GettyImages. The photo was taken by Miss Jiansong Zhang.

4 2 Data and methods The spatio-temporal patterns of pack ice differ significantly in Prydz Bay. RV Xuelong reaches Prydz Bay in early austral summer every year for the resupply and staff transfer. Half-hourly inbound waypoints of RV Xuelong route to Zhongshan Station, Prydz Bay, during the 28 th -30 th CHINARE MODIS imagery, sea-ice concentration (SIC) data retrieved from SSMIS and AMSR-2 data, as well as Envisat-ASAR and RADARSAT-2 SAR images were used for ice navigation. Mean Sea Level Pressure (MSLP) and wind data from the European Centre for Medium- Range Weather Forecasts' (ECMWF's) ERA- Interim reanalysis.

5 The workflow of the route planning for RV Xuelong The first two steps (top left and right box) usually took hour. One full iteration of route planning and assessment would take about 2-3 hours.

6 3 Navigational analysis RV Xuelong, ice-strengthened to Class B1, is the only Chinese polar scientific research vessel and operates in both, the Arctic and Antarctic. Per design she may travel at 1.5 knots while breaking ice of up to 1.1 m thickness (including about 0.2 m of snow). Generally, she would travel at a speed of 12 knots for SIC less than 30%, 8-10 knots for SIC between 30 and 50%, 5-8 knots with SIC ranging from 50 to 70%, less than 5 knots with SIC is within 70 to 90%, and would risk to become beset at SIC greater than 90%. (Captain Quan SHEN, RV Xuelong, personal communication)

7 3.1 Ice navigation in 2011 SIC distribution from SSMIS on 23 Nov Six-hour MSLP fields, overlain with 10-meter winds, at 00:00 UTC on November 25, 27, and 29 in In 23 Nov 2011, SIC was below 90% and as low as 70% in parts between 77 and 78 E. SAR A ridge of high pressure moved north of Prydz Bay, giving rise to minor modification in MSLP. Wind speeds were below 5 m s -1 on Nov 25 and below 10 ms -1 on Nov 27 and 29. fair weather in the following days.

8 recommended approach route A proposed route with 20 waypoints was sent to RV Xuelong based on the analysis of sea ice from the ASAR images on Nov 25 and 26. The RV Xuelong was advised to travel in the sea ice east of 76 E. Real route the RV Xuelong progressed smoothly at a speed of 5 to 10 knots after entering the pack ice, and the proposed route had only been slightly adjusted during this part of the voyage. Comparisons between navigation points of RV Xuelong (blue) from Nov 27 to 29 and the planned route (red) based on ASAR data acquired on Nov 25 and 26, 2011 (left).

9 The right panels show progress of the Russian icebreaker through the fast ice off Zhongshan Station based on ASAR data acquired on Nov 22, 25, and 27, Lead idenfication lead was created by Russian icebreaker Vladimir Ignatyuk, providing icebreaking support for M/V Ivan Papanin resupplying Bharati Station.

10 Ice breaker Sisters M/V Ivan Papanin M/V Xue Long

11 3.2 Ice navigation in 2012 SIC distribution from SSMIS on 23 Nov Six-hour MSLP fields, overlain with 10-meter winds, at 00:00 UTC on November 25, 27, and 29 in In 23 Nov 2012, SIC was lower than 70%, especially in the area between 76 and 78 E below 50%, suggesting RV Xuelong could travel at good speed (8-10 knots). MODIS An anticyclone with a wind speed of less than 5 ms -1 was situated over Prydz Bay on Nov 25 and 27. On Nov 29 a cyclone was moving to the east. The surface meteorological conditions worsened, nevertheless the SIC reduced.

12 Sea ice in the region of interest as seen in composite Terra and Aqua MODIS imagery acquired on November 23 (left) and 25 (right), The blue squares are the navigation GPS points of RV Xuelong from November 28 to December 3, The zone delineated by the two red lines presents the recommended approach route recommended approach route RV Xuelong was advised to travel in the longitude band between 76 and 78 E and to pass through 66.5 S to reach the Prydz Bay Polynya by November 28, 2012 to avoid sea ice variation due to the low-pressure system Real route RV Xuelong took less than 20 hours at an average speed of 10.2 knots to pass through sea ice in Prydz Bay and reach the polynya.

13 3.3 Ice navigation in 2013 SIC distribution from SSMIS on 23 Nov Six-hour MSLP fields, overlain with 10-meter winds, at 00:00 UTC on November 25, 27, and 29 in In Nov 2013, SIC was much higher than that in 2011 or 2012, exceeding 90%. There were hardly any leads. SAR Two cyclones appeared the northern area of Prydz Bay. The wind speed on Nov 29 was less than 5-6 ms -1 in north of Prydz Bay. It would be cloudy with weak winds from Nov 27 to 30.

14 Comparisons between navigation GPS points of RV Xuelong from November 30 to December 2, 2013 and the proposed routes based on MODIS (left) and RADARSAT-2 SAR imagery (right), both acquired on November 29, The MODIS image was a composite using Terra-MODIS and Aqua-MODIS acquired on November 29, There were not many leads visible to the south of 65 S in the SAR image on Nov 27. It was impossible for RV Xuelong to pass the compact pack ice region. The MODIS image was sufficiently clear to identify leads and floe boundaries. A proposed route with 12 waypoints was identified. The waypoint information was sent to RV Xuelong on Nov 28 and updated again on 29, within about 4 hours of the next RADARSAT-2 SAR data being acquired. Real route RV Xuelong succeeded in passing through the pack ice at an average speed of 6.4 knots over 2 days along the proposed route.

15 The process of RV Xuelong breaking off from the pack ice Depression, East Antarctica in January in the Adélie Rapid changes in the ice edge and ice concentration from MODIS images in the Adélie Depression, East Antarctica during besetment of RV Xuelong in January MODIS data could be used as a sole data source for navigation because of the high frequency of revisits.

16 3.4 Ice navigation in 2014

17 Fast ice interpretation using high resolution satellite image Landsat 8 OLI, Radarsat 2,

18 GF 2 Pan image

19 4 Discussions NWP data do adequately depict the weather changes, which then induce SIC variability and hence provide information to assess the need to order SAR data. Daily SIC data remain invaluable for large-scale route planning but improper to ice navigation. MODIS data or other data with a high repeat frequency are likely to play important roles in ice navigation. SAR imagery provides accurate ice information to support ice navigation in the Antarctic on a regional or local scale.

20 Generally, there would be a time lag of approximately 4-6 hours from satellite data acquisition, data processing, and route designs to the transfer of information to RV Xuelong. For ice navigation route proposals based on a range of remotely sensed data proofed successful with some adjustments.

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22 Mass: 10kg Dimension: 27cm cube Polar ice monitoring CO2 density measurement(experimental) Orbit: 600km altitude, sun synchronous, 10:30 LTDN 2015/5/22 WNISAT 1, Nov.21, 2013 Red, Near Infrared Spectral bands:blue, Green, Ground resolution:500 m Capture area:500 x 500 km WNISAT-1 focuses on the ice monitoring mission in summer, which enables it to be practical enough for the client, albeit a very low-cost micro-satellite.

23 Mission Definition: TW1 Mission Targets/Tasks 3 cubesats networking based on Gamalink and CSP Monitoring sea ice in polar region Gaining the maritime traffic information in polar region Demonstration of autonomous formation flight IOD & validation of ADS-B / Gamalink / Micro-propulsion / GPS-BD receiver Orbit: 480km, 8:00am, SSO Launch time:

24 TW-1 Satellites Configuration TW-1A: 3U CubeSat Gamalink Camera TW-1A GPS/BD Receiver Micropropulsion S-band transmitter TW-1B: 2U CubeSat Gamalink AIS receiver GPS/BD receiver TW-1C: 2U CubeSat Gamalink ADS-B Receiver GPS/BD receiver TW-1B TW-1C 24

25 25 TW-1A

26 Introduction to BNU Polar UAV Team GCESS BNU

27 BNU Polar UAV Team Now: 3 Types, 6 Drones 3 Pilots Successful cases both in Arctic & Antarctica Target till December 2015: 4-5 Types, near 10 Drones 4-5 Pilots

28 2 Types of Rotor UAV Drones 1 Type of Fixed-wind UAV

29 DJI PHANTOM - 2 Weight: 1 kg Working Height: m Max continuous working time: 15 min Successful cases: Jan Mayen (70 N) Ny-Alesund (79 N) Monacobreen(Monaco Glacier) (80 N)

30 DJI PHANTOM - 2 Ny-Alesund

31 Polar Elf - 1 Weight: 6-11 kg Working Height: 10m- 200m Max continuous working time: 20 min Mapping resolution: <0.1m

32 Polar Elf - 1 Now: Ny-Alesund, Arctic ( 9 successful flights) Coming case King George Island, Antarctica (Dec. 2015)

33 Polar Elf - 1 Pilot Mr. Li and Polar Elf 1 at Ny Alesund, April 30 th

34 Polar Hawk - 1 Weight: 7 kg Working Height: m Max Continuous Working Time: 75 min Mapping resolution: m Successful cases: Ny-Alesund, Arctic (2014.8) Larsemann Hills, Antarctica ( )

35 Polar Hawk - 1 Taking off at Ny-Alesund, August 2014

36 Successful Cases August 2014: Ny-Alesund, Svalbard, Arctic December February 2015 (CHINARE 31): Larsemann Hills, Antarctica April 2015: Ny-Alesund, Svalbard, Arctic

37 Ny-Alesund 2 flights: 1 test flight & 1 complete course 107 images have been obtained DOM, DEM & 3D Model data of nearby glaciers have been processed Flying route and the controling interface

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41 Digital Elevation Model (DEM)

42 3D Model 872 m 30 m

43 Larsemann Hills 6 flights: 2 test flights & 4 complete courses 2240 images have been obtained DOM, DEM & 3D model data have been processed

44 Larsemann Hills Flying routes above Larsemann Hills

45 Larsemann Hills DOM of Larsemann Hills

46 Larsemann Hills DEM of Larsemann Hills

47 Larsemann Hills A part of the 3D model of Larsemann Hills

48 Zhongshan Station (CHINA)

49 Law Base (AUSTRALIA)

50 Balti Station (INDIA)

51 Ny-Alesund 9 flights: 7 test flights & 2 complete course 451 images have been obtained 3 videos have been obtained, total time 16 minutes 37 seconds Flying route and the controling interface

52 Ny-Alesund Snapshot of working at on Austre Lovenbreen, Ny-Alesund

53 Ny-Alesund Nadir view image of snowmobile ruts from height of 50 meters

54 Ny-Alesund Oblique image of the front of Austre Lovenbreen, Ny-Alesund

55 THE END TNANK YOU