Comparison between C band synthetic aperture radar and 3-D laser scanner statistics for the Baltic Sea ice

2010 ◽  
Vol 115 (C10) ◽  
Author(s):  
M. Similä ◽  
M. Mäkynen ◽  
I. Heiler
Keyword(s):  
Sea Ice ◽  
Synthetic Aperture Radar ◽  
Baltic Sea ◽  
Laser Scanner ◽  
Synthetic Aperture ◽  
The Baltic Sea ◽  
The Baltic ◽  
Aperture Radar

scholarly journals BEPERS pilot study: an experiment with X-band synthetic aperture radar over Baltic Sea ice

1992 ◽  
Vol 38 (128) ◽  
pp. 23-35 ◽  
Author(s):  
Matti Leppäranta ◽  
Rlsto Kuittinen ◽  
Jan Askne
Keyword(s):  
Pilot Study ◽  
Sea Ice ◽  
Synthetic Aperture Radar ◽  
Baltic Sea ◽  
Open Water ◽  
Synthetic Aperture ◽  
Speckle Reduction ◽  
X Band ◽  
Sar Imagery ◽  
Aperture Radar

Abstract Remote-sensing methods are the primary ones used for ice mapping in the Baltic Sea. A major methodological improvement is now being introduced by satellite radars due to their weather independency and high resolution. To learn how to use ERS-1 synthetic aperture radar (SAR) data, an extensive field programme BEPERS (Bothnian Experiment in Preparation for ERS-1) with airborne SARs has been arranged. The BEPERS pilot study was undertaken in 1987 using the French VARAN-S X-band SAR. The SAR was flown on 1 day over four study areas of size approximately 10 km x 50 km, and intensive validation observations were made. The data were most useful for the education they provided on how to work with SAR in sea-ice mapping. They have been used for developing SAR image-analysis methods, back-scatter modelling investigations and geophysical validation of SAR imagery. Cleaning-up of images consisted of speckle reduction and segmentation. Back-scatter characteristics of undeformed ice and ridges were examined. Ice-type classification was based on the box-classification method. Eight ice types were defined but basically only two types, undeformed ice/open water and deformed ice, could be discriminated. Two basic problems of high practical importance remained: how to discriminate between (1) open water and undeformed ice, and (2) ridged ice and brash ice. The data further showed illustrative examples of SAR imagery over sea ice.

scholarly journals Estimation of degree of sea ice ridging in the Bay of Bothnia based on geolocated photon heights from ICESat-2

2021 ◽  
Vol 15 (6) ◽  
pp. 2511-2529
Author(s):  
Renée Mie Fredensborg Hansen ◽  
Eero Rinne ◽  
Sinéad Louise Farrell ◽  
Henriette Skourup
Keyword(s):  
Sea Ice ◽  
Baltic Sea ◽  
Synthetic Aperture ◽  
The Baltic Sea ◽  
Ice Cloud ◽  
In Situ Observations ◽  
The Difference ◽  
The Baltic ◽  
Time Critical

Abstract. We present a comparison of Ice, Cloud and land Elevation Satellite-2 (ICESat-2) geolocated photon heights and operational ice charts from the Finnish Ice Service in the Bay of Bothnia in spring 2019. We show that ICESat-2 (IS2) retrievals from ice areas with different ridging characteristics, more precisely the degree of ice ridging (DIR), differ significantly. DIR is a particularly useful parameter for ice navigators, as it provides information on how difficult it is to navigate through an area based on e.g. sail heights and distribution of sea ice ridges. DIR estimates are included in ice charts of the Baltic Sea and are based primarily on in situ observations from an active icebreaker fleet. We show that DIR may potentially be estimated from IS2. We also present a comparison of IS2 measurements and Sentinel-1 synthetic aperture radar frames, discussing several individual cases of IS2 photon elevation behaviour over Baltic sea ice. We suggest that IS2 data can be of benefit to international ice services, especially if a time-critical photon height product were to be made available. Furthermore, we show that the difference between highest and mean photon elevations (elevation anomalies) of IS2 correspond to expected ridge sail heights in our study area. Our study is one of the first steps in creating sea ice applications beyond the traditional goal of freeboard and thickness retrieval for IS2.

scholarly journals BEPERS pilot study: an experiment with X-band synthetic aperture radar over Baltic Sea ice

1992 ◽  
Vol 38 (128) ◽  
pp. 23-35
Author(s):  
Matti Leppäranta ◽  
Rlsto Kuittinen ◽  
Jan Askne
Keyword(s):  
Pilot Study ◽  
Sea Ice ◽  
Synthetic Aperture Radar ◽  
Baltic Sea ◽  
Open Water ◽  
Synthetic Aperture ◽  
Speckle Reduction ◽  
X Band ◽  
Sar Imagery ◽  
Aperture Radar

AbstractRemote-sensing methods are the primary ones used for ice mapping in the Baltic Sea. A major methodological improvement is now being introduced by satellite radars due to their weather independency and high resolution. To learn how to use ERS-1 synthetic aperture radar (SAR) data, an extensive field programme BEPERS (Bothnian Experiment in Preparation for ERS-1) with airborne SARs has been arranged. The BEPERS pilot study was undertaken in 1987 using the French VARAN-S X-band SAR. The SAR was flown on 1 day over four study areas of size approximately 10 km x 50 km, and intensive validation observations were made. The data were most useful for the education they provided on how to work with SAR in sea-ice mapping. They have been used for developing SAR image-analysis methods, back-scatter modelling investigations and geophysical validation of SAR imagery. Cleaning-up of images consisted of speckle reduction and segmentation. Back-scatter characteristics of undeformed ice and ridges were examined. Ice-type classification was based on the box-classification method. Eight ice types were defined but basically only two types, undeformed ice/open water and deformed ice, could be discriminated. Two basic problems of high practical importance remained: how to discriminate between (1) open water and undeformed ice, and (2) ridged ice and brash ice. The data further showed illustrative examples of SAR imagery over sea ice.

INVESTIGATIONS OF THE BALTIC SEA COASTAL ZONE ABOVE-WATER PART TOPOGRAPHY DYNAMICS BY MEANS OF TERRESTRIAL LASER SCANNER (SVETLOGORSK CITY, KALININGRAD REGION)

2017 ◽  
Author(s):  
Nikolay Lugovoy ◽  
Nikolay Lugovoy ◽  
Askar Ilyasov ◽  
Askar Ilyasov ◽  
Elena Pronina ◽  
...  
Keyword(s):  
Baltic Sea ◽  
Coastal Zone ◽  
Coastal Erosion ◽  
Laser Scanner ◽  
Terrestrial Laser Scanner ◽  
The Baltic Sea ◽  
Coastal Dynamics ◽  
Kaliningrad Region ◽  
The Baltic

The paper describes application of the terrestrial laser scanner for investigation of coastal dynamics of the Svetlogorskaya Bay, Baltic Sea. Methods of investigation and results of surveys repeated over the two consecutive years for quantification of coastal erosion and slope processes within the coastal zone are presented.

scholarly journals Comparison of Target Detectors to Identify Icebergs in Quad-Polarimetric L-Band Synthetic Aperture Radar Data

2021 ◽  
Vol 13 (9) ◽  
pp. 1753
Author(s):  
Johnson Bailey ◽  
Armando Marino ◽  
Vahid Akbari
Keyword(s):  
Sea Ice ◽  
Synthetic Aperture Radar ◽  
Roc Curves ◽  
Radar Data ◽  
Open Ocean ◽  
Synthetic Aperture ◽  
False Alarms ◽  
Synthetic Aperture Radar Data ◽  
Whitening Filter ◽  
Aperture Radar

Icebergs represent hazards to ships and maritime activities and therefore their detection is essential. Synthetic Aperture Radar (SAR) satellites are very useful for this, due to their capability to acquire data under cloud cover and during day and night passes. In this work, we compared six state-of-the-art polarimetric target detectors to test their performance and ability to detect small-sized icebergs <120 m in four locations in Greenland. We used four single-look complex (SLC) ALOS-2 quad-polarimetric images from JAXA for quad-polarimetric detection and we compared with dual-polarimetric detectors using only the channels HH and HV. We also compared these detectors with single-polarimetric intensity channels and we tested using two scenarios: open ocean and sea ice. Our results show that the multi-look polarimetric whitening filter (MPWF) and the optimal polarimetric detector (OPD) provide the most optimal performance in quad- and dual-polarimetric mode detection. The analysis shows that, overall, quad-polarimetric detectors provide the best detection performance. When the false alarm rate (PF) is fixed to 10-5, the probabilities of detection (PD) are 0.99 in open ocean and 0.90 in sea ice. Dual-polarimetric or single-polarimetric detectors show an overall reduction in performance (the ROC curves show a decrease), but this degradation is not very large (<0.1) when the value of false alarms is relatively high (i.e., we are interested in bigger icebergs with a brighter backscattering >120 m, as they are easier to detect). However, the differences between quad- and dual- or single-polarimetric detectors became much more evident when the PF value was fixed to low detection probabilities 10-6 (i.e., smaller icebergs). In the single-polarimetric mode, the HV channel showed PD values of 0.62 for open ocean and 0.26 for sea ice, compared to values of 0.81 (open ocean) and 0.77 (sea ice) obtained with quad-polarimetric detectors.

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