RECOMMENDATIONS - Revision history

Admin at 14:11, 4 March 2021

2021-03-04T14:11:48Z

2020-11-12T11:44:09Z

2020-11-12T11:43:44Z

‎How to tackle false/missed alarms with the GFMS

2020-11-12T11:43:21Z

‎How to tackle false/missed alarms with the GFMS

2020-11-12T11:40:18Z

‎How to tackle false/missed alarms with the GFMS

2020-11-12T11:39:44Z

← Older revision		Revision as of 14:11, 4 March 2021
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		+	[[File:example7.jpg\|right\|100px\|caption]]
	[[GFMS \| [Home]]]		[[GFMS \| [Home]]]
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 As the '''[[Advisory Flags]]''' can only be retrieved at a coarser resolution, we do not forward the information of the flags to the masking or to the '''[[Exclusion Mask]]'''. <br>
 As coming in the form of the additional layer, it should guide the users when interpreting the product, allowing additional insight on its local reliability at the time of Sentinel-1 acquisition.
 ----
 [[GFMS | [Home]]]

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 '''Dynamic effects''' triggered by weather conditions
 * meteorological features ('''strong wind''', '''heavy rainfall''')
-* meteorological-induced state of the soil ('''soil dryness''', '''frozen ground''', or '''wet snow'''
+* meteorological-induced state of the soil ('''soil dryness''', '''frozen ground''', or '''wet snow''')
 are flagged by the dynamic '''[[Advisory Flags]]'''. The '''[[Advisory Flags]]''' indicate locations where the SAR data might be disturbed by such processes during the acquisition, but leaves the flood and water extent layers unmasked.

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 The aforementioned challenges are the classified into '''Static effects''' and '''Dynamic effects''' with the first bound to the ground surface, land cover or topography, and the latter resulting from meteorological dynamics. This is also done with the perspective on a performant global NRT processing. <br>
 As a note: <u>static</u> is understood here with respect to the GFMS reprocessing cycle, i.e., static layers remain unchanged during NRT processing, but they might be updated in the course of a reprocessing after evolution activities.
 '''Static effects''' bound to ground surface characteristics like:
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 are addressed by the '''[[Exclusion Mask]]'''. <br>
 Pixels that could not be classified by the SAR sensor into flood area, permanent/seasonal water body, and non-water area, are highlighted in this product layer as no-data pixels.
 '''Dynamic effects''' triggered by weather conditions
@@ Line 44: / Line 46: @@
 * meteorological-induced state of the soil ('''soil dryness''', '''frozen ground''', or '''wet snow'''
 are flagged by the dynamic '''[[Advisory Flags]]'''. The '''[[Advisory Flags]]''' indicate locations where the SAR data might be disturbed by such processes during the acquisition, but leaves the flood and water extent layers unmasked.
 Both layers are delivered with the '''[[PRODUCTS | other flood product layers]]''' and aim at improving the reliability, usefulness and user acceptance of the GFMS product. <br>

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 The aforementioned challenges are the classified into '''Static effects''' and '''Dynamic effects''' with the first bound to the ground surface, land cover or topography, and the latter resulting from meteorological dynamics. This is also done with the perspective on a performant global NRT processing. <br>
-As a note: <u>Static</u> is understood here with respect to the GFMS reprocessing cycle, i.e., static layers remain unchanged during NRT processing, but they might be updated in the course of a reprocessing after evolution activities.
+As a note: <u>static</u> is understood here with respect to the GFMS reprocessing cycle, i.e., static layers remain unchanged during NRT processing, but they might be updated in the course of a reprocessing after evolution activities.
-'''Static effects'''bound to ground surface characteristics like:
+'''Static effects''' bound to ground surface characteristics like:
 * land cover (e.g., '''flat impervious areas''', '''urban areas''', '''densely vegetated areas''')
 * shadowing ('''radar shadowing''')

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 In particular, wind and heavy rainfall are hard-to-spot dynamic process as they roughen water surfaces and hence undermine the initial assumption of low backscatter due to specular reflection on smooth water surfaces.
-== How false/missed alarms are tackled in the GFMS==
+== How to tackle false/missed alarms with the GFMS==
 This discuss the abovementioned issues of SAR-based water mapping which potentially cannot be directly solved by the proposed flood detection algorithms using only NRT-available backscatter information and hence indication need on pixel level for potential misclassification due to reduced sensitivity. <br>