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Reposted by Elizabeth Wig

Dr. Rowena Lohman @rowenalohman.bsky.social · Jul 30

Let's go NISAR!!! Successful separation - now we wait on the rest of the deployment over the next week or so. #nisar #isro #nasa
science.nasa.gov/blogs/nisar/...

NASA-ISRO’s NISAR Spacecraft Separates From Rocket’s Third Stage - NASA Science

The NISAR (NASA-ISRO Synthetic Aperture Radar) spacecraft has separated from the third stage of ISRO’s Geosynchronous Satellite Launch Vehicle rocket and will

science.nasa.gov

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Reposted by Elizabeth Wig

Leah Clayton @leah-clayton.bsky.social · Mar 25

joining bluesky 🦋 | scientist + artist who thinks a lot about the intersection between the geophysical and ecological, climate futures, and resilience

A photograph of Lake Tahoe with a bright blue sky and a large tree in the center. A small inset of a black and white linocut print of the photograph.

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Elizabeth Wig @elizabethwig.bsky.social · Jan 23

Permafrost is important for so many reasons – it's a natural carbon reservoir, the base for infrastructure, and a home to many species. Understanding how it's changing and the downstream effects of these changes is so important for making good decisions about all these things!

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Elizabeth Wig @elizabethwig.bsky.social · Jan 23

Greening trends appear associated with smaller seasonal subsidence, thinner active layers, and wetter soil:

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Elizabeth Wig @elizabethwig.bsky.social · Jan 23

Burned areas have higher soil water content than unburned areas:

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Elizabeth Wig @elizabethwig.bsky.social · Jan 23

Lower soil moisture (volumetric water content) is associated with deeper active layers, suggesting that Arctic soil may become drier as the climate warms:

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Elizabeth Wig @elizabethwig.bsky.social · Jan 23

This data set measures subsidence, soil moisture, and active layer thickness of #permafrost at millions of points. This allows us to investigate what processes and relationships from smaller-scale studies hold over larger regions. What do we discover? ⤵️

Map showing swaths included in the Permafrost Dynamics Observatory's ABoVE: Active Layer Thickness from Airborne L- and P- band SAR, Alaska, 2017

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Elizabeth Wig @elizabethwig.bsky.social · Jan 23

🚨 New paper alert! 🚨

Permafrost Dynamics Observatory: Remote Sensing Big Data for the Active Layer, Soil Moisture, and Greening and Browning

We analyze a big dataset of airborne L-band SAR data over permafrost in the Arctic-Boreal region

agupubs.onlinelibrary.wiley.com/doi/full/10....

Permafrost Dynamics Observatory: 3. Remote Sensing Big Data for the Active Layer, Soil Moisture, and Greening and Browning

Lower soil volumetric water content associated with deeper active layers suggests that Arctic soil may become drier as the climate warms Burned areas have higher soil water content than unburned ...

agupubs.onlinelibrary.wiley.com

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Reposted by Elizabeth Wig

Scripps Institution of Oceanography @scrippsocean.bsky.social · Dec 13

A satellite-mounted instrument has in just one year produced higher-resolution imagery of the global seafloor than that from comparable systems over the past 30 years. 'Sea' for yourself and learn more about the new study led by Scripps Oceanography postdoctoral scholar Yao Yu. ⬇️

SWOT Sharpens Seafloor Focus

A satellite-mounted instrument has in just one year produced higher-resolution imagery of the global seafloor than that from comparable systems over the past 30 years.

scripps.ucsd.edu

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Reposted by Elizabeth Wig

Elizabeth Eiden @elizabetheiden.bsky.social · Dec 9

At #AGU24? Interested in volcanoes? Interested in Venus? Come chat with me at my poster this afternoon! Poster number 3121

Scientific poster titled “Quantifying volcanism on Venus with VenSAR: Comparison with Earth and Suggestions for Targeted Observations”

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Elizabeth Wig @elizabethwig.bsky.social · Dec 9

Happy #AGU24! If you're interested in learning about how InSAR closure phase can be used to measure moisture in soil, vegetation, or wildfire fuel materials, check out my poster Wednesday morning and talk Wednesday evening!

Remotely Sensed Fuel Moisture from InSAR Closure Phase on UAVSAR
Elizabeth Wig et al, Hall B-C (Poster Hall) (Convention Center)
Wednesday, 11 December 2024 : 08:30 - 12:20

InSAR Closure Phase for Fine-Resolution Measurements of Changing Soil and Vegetation Moisture, Elizabeth Wig et al, Marquis 1-2 (Marriott Marquis), Wednesday, 11 December 2024 : 17:00 - 17:10

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Elizabeth Wig @elizabethwig.bsky.social · Dec 5

Everything going according to plan in the Sentinel-1C launch so far... excited and hopeful for more InSAR data to come!

Streaming right now at www.esa.int/ESA_Multimed...

Image of rocket moving through sky from livestream of Sentinel-1C satellite launch

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Elizabeth Wig @elizabethwig.bsky.social · Dec 4

Would love to join this community! :)

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Elizabeth Wig @elizabethwig.bsky.social · Nov 19

Interested in joining too, thanks for organizing!

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Elizabeth Wig @elizabethwig.bsky.social · Aug 2

I hope you'll check our paper out if you have any interest in SAR, InSAR, or remote sensing of soil moisture or vegetation -- and please let me know if you have any questions 😊

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Elizabeth Wig @elizabethwig.bsky.social · Aug 2

We also show that systematic bias in the closure phase can be caused by asymmetries in the time series, where wetting and drying happen at different rates. A more asymmetric time series (wetting is much faster or slower than drying) tends to produce a more "biased" time series.

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Elizabeth Wig @elizabethwig.bsky.social · Aug 2

Estimation of soil moisture is poorer over crop land, likely because of changing vegetation. We characterize the accuracy of our estimate across different land cover types.

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Elizabeth Wig @elizabethwig.bsky.social · Aug 2

We show that cumulative InSAR closure phase can be used to estimate soil moisture at 37 sites, validating with in situ measurements in Oklahoma. The estimates can be quite accurate!

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Elizabeth Wig @elizabethwig.bsky.social · Aug 2

We use a model and real data to show that, because closure phase relates to *changes* in scattering properties, you can *cumulatively sum* a closure phase time series -- as a new way to measure soil moisture!

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Elizabeth Wig @elizabethwig.bsky.social · Aug 2

InSAR closure phase is the result of combining radar signals from satellite overpasses from 3 different times. It's particularly sensitive to changing scattering properties on the ground, such as changes in soil moisture.

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Elizabeth Wig @elizabethwig.bsky.social · Aug 2

My first first-author paper is finally published! 🥳🛰️
"Fine-Resolution Measurement of Soil Moisture from Cumulative InSAR Closure Phase"
This is the cumulative work of the 1st half of my PhD, and I'm so excited to be able to share the final product! 😄
bit.ly/closuresoil

Fine-Resolution Measurement of Soil Moisture From Cumulative InSAR Closure Phase

Soil moisture can vary spatially at the scale of agricultural fields (~10–100 m), which is generally too fine to resolve using passive radiometric methods. Active radar provides an opportunity for fin...

bit.ly

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Elizabeth Wig @elizabethwig.bsky.social · Jul 6

Going to IEEE #IGARSS2024?

Come say hi - and check out my presentation on measuring changes in vegetation moisture from InSAR closure phase! Tuesday, 11:40 in the Student Paper Competition session 😎🛰🌲

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Elizabeth Wig @elizabethwig.bsky.social · Mar 4

If you use SBAS or distributed scatterer time series for InSAR, you may be unknowingly aliasing your data! A new paper by my labmate Karissa Pepin explores how aliasing sneaks into InSAR time series & how to tailor temporal baselines to minimize this effect: bit.ly/aliasinsar

Aliasing in InSAR 2-D Phase Unwrapping and Time Series

We quantify and characterize an often-overlooked error source in interferometric synthetic aperture radar (InSAR) and derived time series: aliasing from insufficiently sampled interferograms in space ...

bit.ly

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Elizabeth Wig @elizabethwig.bsky.social · Dec 11

…Or to come to watch me present, also tomorrow (Tues) 9:10-9:20 a.m., on what the results from the @ABoVE Permafrost Dynamics Observatory can tell us about the dynamic active layer soil moisture, and greening and browning

B21D-05 Results from the ABoVE Permafrost Dynamics Observatory: What Remote Sensing Big Data Tells Us about the Dynamic Active Layer, Soil Moisture, and Greening and Browning. Elizabeth Wig. 3006 - West (Level 3, West, MC)

Elizabeth Wig @elizabethwig.bsky.social · Dec 11

AGU23 has me wishing I could split myself in half!

Tomorrow (Tues) from 9:10-9:20 a.m., I encourage you to watch my advisor discuss our work on modelling InSAR closure phase to measure high-resolution soil moisture…

G21A-05 InSAR and Fine-Resolution Measurement of Soil Moisture: An Interference Scattering Model for Nonzero Phase Closure. Howard Zebker. 158-South (Upper Mezzanine, South, MC)

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