Images

Format Specifications (single band - Depth)

MBES backscatter is measured by transmitting acoustic signals to the seafloor and analysing the strength of the returned signals, which depend on impedance contrast (hardness) and surface roughness. Higher backscatter intensity generally indicates rougher or harder surfaces. The raw data undergoes corrections for beam pattern, transmission loss, and angle of incidence. Calibration with reference areas and ground truthing with sediment or imagery samples ensures accuracy. Backscatter intensity, expressed in decibels, represents the ratio of incident and scattered waves. Processing includes georeferencing, radiometric and geometric corrections, angular dependence correction, and beam pattern adjustments, producing a backscatter mosaic and angular backscatter response curves.

Measurement type:	Backscatter
File format:	GeoTIFF
File:
Data type:	32bit floating point
Data/Pixel units	metres
Band number:	1
Description:	Multibeam backscatter measures the intensity of acoustic signals reflected from the seafloor, providing detailed information about its physical properties, such as composition and texture, which is essential for seafloor characterisation and habitat mapping.
No data value:	NaN
Valid data range:	[10 to –250]
Tiled with X and Y block sizes:	[512, 512]
Compression:	Deflate, Level-6 predictor-3
Pyramids:	Yes. Levels will be [8, 16, 32]. Compress the pyramids using deflate. Bi-linear resampling
Output Coordinate Reference System (CRS):	EPSG 4326 (geographic decimal degrees); except where source is UTM using WGS84
Horizontal Datum:	WGS84
H_Output Units:	Variable (Geographic - decimal degrees, UTM – metres)
V_Output Units:	dB
Output name:	filename \|\| .TIFF

Table 4. Format specifications for a single band MBES intensity GeoTIFF.