Measuring Change with Radar Imagery_Richard Goodman - Intergraph Geospatial World Tour 2013

transcript

SMARTERDECISIONS

Richard Goodman

Intergraph (UK) Ltd

Measuring Change With RADAR Imagery

Why is change measurement important

Why is change measurement important?

Devastation caused by tornadoes in Alabama, 2011

Magnitude 9.0 earthquake in Japan, 2011

Mississippi river flooding in Memphis, Tennessee, 2011

UK Floods, 2007

Oil spills

So why use RADAR data in change

measurement

The Mysterious RADAR image…

Why use RADAR data in change measurement?

• Active sensor• No sun illumination required

• Imagery collected in cloudy weather

• Pulse sent from sensor, reflected off features, return captured by

antenna

• SINGLE LOOK COMPLEX (SLC) data format• RADARSAT 1 / 2, COSMO-SkyMed, TerraSAR-X

• 2 bands of data

• Magnitude (strength of return)

• Phase (position of wave on return to antenna)

• Man-made features and infrastructure give

strong returns• Buildings

• Steel/metals

• Sub-surface features

• Interferometric processing• Interferometric pairs

• Make use of both magnitude and phase layers

• Coherence Change Detection (CCD)

• Differential Interferometric Displacement Mapping (D-InSAR)

• Accuracy to cm level

• Monitoring subsidence• Subsurface oil and water extraction

• Mining

• Natural disasters – earthquakes, volcanoes

• Human activities

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ERDAS Imagine Radar Tools

• Radar Mapping Suite• Add-on module

• Operational software• Not a toolkit!

• Directly read data into viewer• No import required

• No resampling of data

• New Radar Analyst ribbon• Fast feature extraction

• Visualisation aids

• Interferometry tools• CCD

• D-InSAR

• New Radar Analyst ribbon

• Interferometry tools – CCD & D-InSAR

• Wizard-based workflows• Intelligent defaults for parameters

• Experts can take full control

• Phase Un-Wrap algorithm• The heart of the CCD and D-InSAR

• Developed in conjunction with German Aerospace Agency (DLR)

3. Visual Interpretation

4. Automatic Detection

1. Project Setup2. Processing Steps

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Case Studies

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Data Analysis and Classification Tool

KSAT DACT Case Study

• Who/What is KSAT

• Kongsberg Satellite Services AS (KSAT) is a commercial

Norwegian enterprise

• Provides services to European Maritime Safety Agency to detect

and report oil spills using RADAR satellite imagery

• Locations

Tromsø Station & Offices at 69°39´N 18°56´E.

80 Employees

Svalbard Satellite Station (SvalSat) at 78°15´N 15°80´E

19 employees

Grimstad, (South Norway) at 58°20´N 8°21´E

4 employees

And TrollSat (Antarctica) at 72°S 2°E – That s far far south…

• The DACT Project

• KSAT has provided a service using satellite images for detection of

oil spills since 1994

• Can deliver oil spill reports to European end users promptly

• New user requirements had KSAT develop the Data Analysis and

Classification Tool with emphasis on oil spill and vessel detection

from satellite imagery

• Radar imagery ideal for quickly identifying oil spills and linking them

to possible sources (vessels/platforms)

• The System

• Customised Imagine ribbon interface with KSAT tab

• Contains shortcuts to common tools used in identification, extraction

of oil spills

• External data sources, shipping tracks, wind, wave, current, oil

platforms used to identify possible sources of spill

• Reports generated for each radar scene (clean sea, warning,

notification)

• Target turnaround time is 30 minutes from when imagery available to

report sent

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Interferometry Tools Examples

Qualitative Change Mapping with CCD

Geoinformatics magazine, July/August 2010

Qualitative Change Mapping with CCD

Magnitude Change Coherence ChangePhase CoherenceAverage Radar Magnitude

Quantitative Change Mapping with D-InSAR

Using the IMAGINE D-InSAR tool users can map VerticalDisplacement

Max Subsidence = -16.5 cm

Max Uplift = +26.6 cm

Published Displacement: +30/-18

Xia,Ye. Bam earthquake: Surface deformation measurement using radar interferometry. ActaSeismologicia Sinica, Vol.18 No.4 (451~459), July, 2005

Summary – Operational Change Measurement Workflow

Input raw RADAR data

Detected change

Report

Vector output

Questions?

Measuring Change with Radar Imagery_Richard Goodman - Intergraph Geospatial World Tour 2013

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