Applicability of InSAR to tropical volcanoes: insights from Central America

Abstract Measuring volcano deformation is key to understanding the behaviour of erupting volcanoes and detecting those in periods of unrest. Satellite techniques provide the opportunity to do so on a global scale but, with some notable exceptions, the deformation of volcanoes in the tropics has been understudied relative to those at higher latitudes, largely due to technical difficulties in applying Interferometric Synthetic Aperture Radar (InSAR). We perform a systematic survey of the Central American Volcanic Arc to investigate the applicability of Interferometric Synthetic Aperture Radar (InSAR) to volcanoes in the tropics. Volcano characteristics that may prevent InSAR measurement include: (1) dense vegetation cover; (2) persistent activity; and (3) steep slopes. Measurements of deformation are further inhibited by atmospheric artefacts associated with: (4) large changes in topographical relief. We present a systematic method for distinguishing between water vapour artefacts and true deformation. Our data show a linear relationship (c. 2 cm/km) between the magnitudes of water vapour artefacts and volcano edifice height. For high relief volcanoes (e.g. Fuego, Guatemala, 3763 m a.s.l. (above sea level)) errors are of the order of 4–5 cm across the volcano's edifice but are less than 2 cm for lower relief (e.g. Masaya, Nicaragua, 635 m a.s.l.). Examples such as Arenal, Atitlan and Fuego illustrate that satellite acquisition strategies incorporating ascending and descending tracks are particularly important for studying steep-sided volcanoes. Poor coherence is primarily associated with temporal decorrelation, which is typically more rapid in southern Central America where Evergreen broadleaf vegetation dominates. Land-use classification is a better predictor of decorrelation rate than vegetation index. Comparison of coherence for different radar wavelengths match expectations; high resolution X-band radar is best suited to local studies where high-resolution digital elevation models (DEMs) exist, while L-band wavelengths are necessary for regional surveys. However, this is the first time that relationships between phase coherence and time, perpendicular baseline, radar wavelength, and land use have been quantified on the scale of a whole volcanic arc.

[1]  Peter J. Clarke,et al.  Atmospheric models, GPS and InSAR measurements of the tropospheric water vapour field over Mount Etna , 2002 .

[2]  J. M. Moore,et al.  Land surface change detection in a desert area in Algeria using multi-temporal ERS SAR coherence images , 2001 .

[3]  M. J. Carr Symmetrical and segmented variation of physical and geochemical characteristics of the central american volcanic front , 1984 .

[4]  Marie-Pierre Doin,et al.  Systematic InSAR tropospheric phase delay corrections from global meteorological reanalysis data , 2011 .

[5]  T. Wright,et al.  Multi-interferogram method for measuring interseismic deformation: Denali Fault, Alaska , 2007 .

[6]  E. Rodríguez,et al.  A Global Assessment of the SRTM Performance , 2006 .

[7]  Maurizio Santoro,et al.  Stem volume retrieval in boreal forests from ERS-1/2 interferometry , 2002 .

[8]  G. Wadge,et al.  Towards Operational Repeat-Pass SAR Interferometry at Active Volcanoes , 2004 .

[9]  Mark Simons,et al.  A survey of volcanic deformation on Java using ALOS PALSAR interferometric time series , 2011 .

[10]  Virginie Pinel,et al.  The challenging retrieval of the displacement field from InSAR data for andesitic stratovolcanoes: Case study of Popocatepetl and Colima Volcano, Mexico , 2011 .

[11]  T. Herring,et al.  GPS Meteorology: Remote Sensing of Atmospheric Water Vapor Using the Global Positioning System , 1992 .

[12]  Johan E. S. Fransson,et al.  Stem volume estimation in boreal forests using ERS-1/2 coherence and SPOT XS optical data , 2001 .

[13]  G. Wadge,et al.  Correction of atmospheric delay effects in radar interferometry using a nested mesoscale atmospheric model , 2010 .

[14]  Zhong Lu,et al.  Ground surface deformation patterns, magma supply, and magma storage at Okmok volcano, Alaska, from InSAR analysis , 2010 .

[15]  R. Hanssen Radar Interferometry: Data Interpretation and Error Analysis , 2001 .

[16]  Peter W. Webley,et al.  Determining radio wave delay by non-hydrostatic atmospheric modelling of water vapour over mountains , 2004 .

[17]  Pierre Briole,et al.  Volcano‐wide fringes in ERS synthetic aperture radar interferograms of Etna (1992–1998): Deformation or tropospheric effect? , 2000 .

[18]  James Foster,et al.  Mitigating atmospheric noise for InSAR using a high resolution weather model , 2005 .

[19]  Manoochehr Shirzaei,et al.  Topography correlated atmospheric delay correction in radar interferometry using wavelet transforms , 2012 .

[20]  Fabio Rocca,et al.  Permanent scatterers in SAR interferometry , 2001, IEEE Trans. Geosci. Remote. Sens..

[21]  P. Rosen,et al.  Updated repeat orbit interferometry package released , 2004 .

[22]  Zhong Lu,et al.  Ground surface deformation patterns, magma supply, and magma storage at Okmok volcano, Alaska, from InSAR analysis: 2. Coeruptive deflation, July–August 2008 , 2010 .

[23]  Denis Legrand,et al.  Insight into ground deformations at Lascar volcano (Chile) from SAR interferometry, photogrammetry and GPS data: Implications on volcano dynamics and future space monitoring , 2006 .

[24]  S. Hensley,et al.  SRTM C-band topographic data: quality assessments and calibration activities , 2001, IGARSS 2001. Scanning the Present and Resolving the Future. Proceedings. IEEE 2001 International Geoscience and Remote Sensing Symposium (Cat. No.01CH37217).

[25]  D. Massonnet,et al.  Deflation of Mount Etna monitored by spaceborne radar interferometry , 1995, Nature.

[26]  Howard A. Zebker,et al.  Remote Sensing of Volcano Surface and Internal Processes Using Radar Interferometry , 2013 .

[27]  Rowena B. Lohman,et al.  Some thoughts on the use of InSAR data to constrain models of surface deformation: Noise structure and data downsampling , 2005 .

[28]  F. Webb,et al.  Surface deformation and coherence measurements of Kilauea Volcano, Hawaii, from SIR C radar interferometry , 1996 .

[29]  G. Fornaro,et al.  Modeling surface deformation observed with synthetic aperture radar interferometry at Campi Flegrei caldera , 2001 .

[30]  Tamsin A. Mather,et al.  Measuring large topographic change with InSAR: Lava thicknesses, extrusion rate and subsidence rate at Santiaguito volcano, Guatemala , 2012 .

[31]  T. Wright,et al.  Geodetic observations of the ongoing Dabbahu rifting episode: new dyke intrusions in 2006 and 2007 , 2009 .

[32]  F. Amelung,et al.  Co-eruptive subsidence at Galeras identified during an InSAR survey of Colombian volcanoes (2006–2009) , 2011 .

[33]  K. Feigl,et al.  Radar interferometry and its application to changes in the Earth's surface , 1998 .

[34]  E. Rodríguez,et al.  Theory and design of interferometric synthetic aperture radars , 1992 .

[35]  M. Seymour,et al.  Maximum likelihood estimation for SAR interferometry , 1994, Proceedings of IGARSS '94 - 1994 IEEE International Geoscience and Remote Sensing Symposium.

[36]  Jeffrey T. Freymueller,et al.  Tracking magma volume recovery at Okmok volcano using GPS and an unscented Kalman filter , 2009 .

[37]  Michael E. Martinez,et al.  Geophysical, geochemical and geodetical signals of reawakening at Turrialba volcano (Costa Rica) after almost 150 years of quiescence , 2010 .

[38]  Rui Zhang,et al.  Surface deformation associated with the 2008 Ms8.0 Wenchuan earthquake from ALOS L-band SAR interferometry , 2010, International Journal of Applied Earth Observation and Geoinformation.

[39]  Jan-Peter Muller,et al.  Interferometric synthetic aperture radar (InSAR) atmospheric correction: GPS, moderate resolution Imaging spectroradiometer (MODIS), and InSAR integration , 2005 .

[40]  Matthew E. Pritchard,et al.  Duration, magnitude, and frequency of subaerial volcano deformation events: New results from Latin America using InSAR and a global synthesis , 2010 .

[41]  P. Rosen,et al.  Atmospheric effects in interferometric synthetic aperture radar surface deformation and topographic maps , 1997 .

[42]  T. Dixon,et al.  Stratovolcano growth by co‐eruptive intrusion: The 2008 eruption of Tungurahua Ecuador , 2010 .

[43]  Juliet Biggs,et al.  Multiple inflation and deflation events at Kenyan volcanoes, East African Rift , 2009 .

[44]  Jan-Peter Muller,et al.  Surface movements of emplaced lava flows measured by synthetic aperture radar interferometry , 2001 .

[45]  H. Balzter Forest mapping and monitoring with interferometric synthetic aperture radar (InSAR) , 2001 .

[46]  Howard A. Zebker,et al.  Decorrelation in interferometric radar echoes , 1992, IEEE Trans. Geosci. Remote. Sens..

[47]  M. Simons,et al.  An InSAR‐based survey of volcanic deformation in the central Andes , 2004 .

[48]  Zhong Lu,et al.  Magmatic activity beneath the quiescent Three Sisters volcanic center, central Oregon Cascade Range, USA , 2002 .

[49]  D. Remy,et al.  Accurate measurements of tropospheric effects in volcanic areas from SAR interferometry data: application to Sakurajima volcano (Japan) , 2003 .

[50]  Paul Siqueira,et al.  A survey of temporal decorrelation from spaceborne L-Band repeat-pass InSAR , 2011 .

[51]  Jan-Peter Muller,et al.  Assessment of the potential of MERIS near‐infrared water vapour products to correct ASAR interferometric measurements , 2006 .

[52]  J. N. Lima,et al.  Seasonal tropospheric influence on SAR interferograms near the ITCZ - The case of Fogo Volcano and Mount Cameroon , 2010 .

[53]  D. Schmidt Time-dependent land uplift and subsidence in the Santa Clara Valley , 2003 .

[54]  G. Wadge,et al.  Steady downslope movement on the western flank of Arenal volcano, Costa Rica , 2010 .

[55]  Glen S. Mattioli,et al.  Ground deformation at Soufriere Hills Volcano, Montserrat during 1998-2000 measured by radar interferometry and GPS , 2006 .

[56]  K. Feigl,et al.  Discrimination of geophysical phenomena in satellite radar interferograms , 1995 .

[57]  Robert W. Bruce,et al.  Theory and design , 2012 .

[58]  Hannes Isaak Reuter,et al.  A first assessment of Aster GDEM tiles for absolute accuracy, relative accuracy and terrain parameters , 2009, 2009 IEEE International Geoscience and Remote Sensing Symposium.

[59]  Thomas Fournier,et al.  Accounting for Atmospheric Delays in InSAR Data in a Search for Long-Wavelength Deformation in South America , 2011, IEEE Transactions on Geoscience and Remote Sensing.

[60]  P. Rosen,et al.  SYNTHETIC APERTURE RADAR INTERFEROMETRY TO MEASURE EARTH'S SURFACE TOPOGRAPHY AND ITS DEFORMATION , 2000 .

[61]  M. Simons,et al.  A multiscale approach to estimating topographically correlated propagation delays in radar interferograms , 2010 .

[62]  C. Werner,et al.  Satellite radar interferometry: Two-dimensional phase unwrapping , 1988 .

[63]  H. Zebker,et al.  Fault Slip Distribution of the 1999 Mw 7.1 Hector Mine, California, Earthquake, Estimated from Satellite Radar and GPS Measurements , 2002 .

[64]  Gianfranco Fornaro,et al.  A new algorithm for surface deformation monitoring based on small baseline differential SAR interferograms , 2002, IEEE Trans. Geosci. Remote. Sens..