Milillo's Lab

Research

We use synthetic aperture radar to measure how the Earth’s surface moves, and how the structures built on it respond. Ice sheets lose contact with their beds. Bridges deflect under load. Ground fails after an earthquake. However, the deformation that matters is often millimetric and short-lived. We exploit the synergistic use of satellite constellations to recover it at mm/year precision, at spatial and temporal scales not reasonably accessible with in situ measurements.

Research themes

Cryosphere and ice-sheet dynamics

Where an ice sheet loses contact with its bed, and how fast that boundary is moving.

The problem

The grounding line is the boundary where an ice sheet stops resting on bedrock and begins to float. It is not a line and it does not hold still: it migrates by kilometres over a single tidal cycle, and it retreats over years as warm ocean water reaches further beneath the ice. Its position sets how much ice is exposed to ocean melt, which is why models are so sensitive to it.

Bedrock Ocean Grounded ice Floating ice shelf Grounding line retreattidal migration warm water intrusion
The grounding line is a zone, not a line. Short-repeat interferometry separates tidal migration (which reverses) from retreat (which does not).

How we measure it

We map the grounding zone from short-repeat radar interferometry. One-day and four-day repeat passes from COSMO-SkyMed, TanDEM-X and Sentinel-1 resolve the tidal flexure hinge directly, so migration can be separated from long-term retreat rather than confounded with it.

What we have found

Thwaites Glacier

Retreat of 0.8 km/yr in the fastest sector, with floating ice melting at 200 m/yr, while adjacent sectors retreat at 0.3 km/yr and melt ten times slower.

Pine Island Glacier

The grounding line migrates over a zone 2.5 km wide at tidal frequencies in 2016-2017, against 0.5 km in 1996.

Model gap

Measured retreat rates outpace what coupled ice-sheet and ocean models anticipate on yearly time scales.

Papers on this theme 19

Showing the 6 most relevant of 19. See all 92 publications.

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Study sites

Where the work happens

Every study site named in the group’s publications. Drag to rotate, scroll to zoom, or pick a site below.

Active & recently awarded grants

Building the Next-Generation Geomatics Workforce Through InSAR, Photogrammetry, LiDAR and Multimodal 3D Reconstruction at the University of Houston

PINGA2026

Uncertainty-Aware NISAR Damage Mapping for Disaster Response

Co-INASA2026Lead PI: Van Den Hoek, Jamon

Interpretable Multi-hazard Damage Assessment with Vision-Language Models and Commercial Satellite Data

Co-INASA2025Lead PI: Hoskere, Vedhus

Rapidly estimating regional earthquake impacts using commercial satellite data

Co-INASA2025Lead PI: Loos, Sabine

Volcano topography science and applications observation needs for STV

Co-INASA2024Lead PI: Lundgren, Paul R

STV Applications Needs

PINASA2024

Surface Topography and Biomass Resolution Needs for Enabling Wildfire and Vegetation-Atmosphere Modeling and Forecasts

Co-INASA2024Lead PI: Momen, Mostafa

Completed projects

COSMO-SkyMed Grounding line Dynamics in Antarctica

PINASA2024

Evaluating Umbra Space High-resolution Data for low-latency multi-hazard Damage Mapping Practices

PINASA2024

Evaluating Umbra high-resolution SAR data for sustainable water management practices and flood inundation forecasts Advancing SAR and Electro-optical data analysis for the FIRE Sense Team

Co-INASA2024Lead PI: Lee, Hyongki

Using high-resolution commercial smallsat and citizen science data for post-earthquake reconnaissance missions

PINASA2023

Evaluating Capella Space high-resolution data for Coastal Monitoring and Sustainable Water Management Practices

PINASA2022

Evaluating ICEYE Space high-resolution data for Coastal Monitoring and Sustainable Water Management Practices

PINASA2022

Earth System Data Record of Ice Motion, Grounding Line, and Bed Topography in Antarctica from NISAR and other sensors

Co-INASA2022Lead PI: Rignot, Eric

New observing strategies for beach and dune topography and implications for coastal flood risk

PINASA2021

Multi-Temporal Anomaly Detection for SAR Earth Observations

Co-INASA2018Lead PI: Hua, Hook

AFRL ML-RCP · Self-supervised optical-SAR fusion

Co-PIAFRLLead PI: Cescon, Marzia

Funding from NASA, the National Geospatial-Intelligence Agency, the Air Force Research Laboratory, the German Aerospace Center (DLR) and the Italian Space Agency (ASI).