Sentinel-1
21 articlesLayover and Shadow: How Much of a SAR Scene Is Actually Usable?
In relief, a large share of a SAR scene can be unmeasurable before you look at it. The geometry is arithmetic — slope against incidence angle — so it can be computed for a specific pass instead of guessed at.
2026-08-23 · 6 min read
Watching a Place: Measuring a Number vs Watching for Events
Continuous satellite monitoring splits into two jobs that get confused constantly — measuring a quantity over a polygon and watching an area for events. Which one you set up decides whether your watch says nothing or says too much.
2026-08-23 · 7 min read
When Can a Satellite Next Image This Place? Pass Prediction, Explained
How satellite access windows are predicted from public orbital elements, why a predicted window is not a guaranteed image, and how to decide between waiting for a free systematic pass and paying to task a commercial one.
2026-08-23 · 7 min read
NISAR L-Band SAR vs Sentinel-1 C-Band: When Does Wavelength Decide the Answer?
NISAR's L-band radar has a 24 cm wavelength against Sentinel-1's 5.55 cm. That single difference changes what the radar sees under vegetation, how coherence behaves, and which sensor answers your question.
2026-08-03 · 8 min read
A Field Guide to Free Satellite Data Sources: Sentinel-1, Sentinel-2, VIIRS, and NASA FIRMS
Four open satellite data sources cover most monitoring needs — but each one sees the world differently. This guide explains what Sentinel-1 SAR, Sentinel-2 optical, VIIRS nighttime lights, and NASA FIRMS active fire each measure, and how to pick the right one.
2026-06-19 · 5 min read
Synthetic Aperture Radar (SAR): The Complete Guide
A complete, structured guide to Synthetic Aperture Radar (SAR) for Earth observation — how SAR works, why it sees through clouds, polarization, backscatter, InSAR, and the full range of applications from flood mapping to ship detection. Your hub for every SAR topic.
2026-06-19 · 5 min read
Multi-Index Satellite Monitoring: Why One Sensor Is Never Enough
Monitoring a site with a single index misses events that only appear in other data streams. Combining NDVI, SAR backscatter, NDWI, and nighttime lights for the same polygon creates a complete picture that no single sensor can provide.
2026-04-12 · 8 min read
Flood Monitoring with Sentinel-1 SAR Time Series: Tracking Inundation from Space
SAR backscatter time series from Sentinel-1 detects flood onset, peak inundation, and recession through clouds. Learn how VV backscatter drops indicate flooding, how to set up continuous flood monitoring zones, and how to interpret SAR time series for disaster response.
2026-04-11 · 9 min read
Coastal Change Monitoring with NDWI and SAR Time Series
Coastal zones are among the most dynamic and threatened environments on Earth. NDWI time series from Sentinel-2 and SAR from Sentinel-1 together provide continuous monitoring of shoreline change, mangrove extent, coral reefs, and tidal dynamics. Learn how to set up multi-index coastal monitoring.
2026-04-06 · 8 min read
Forest Health Monitoring with NDVI and SAR Vegetation Indices
Combining Sentinel-2 NDVI with Sentinel-1 SAR indices like RVI and RFDI provides comprehensive forest health monitoring that works through clouds. Learn how optical and radar time series complement each other to detect deforestation, degradation, and stress before it becomes visible to the naked eye.
2026-04-02 · 8 min read
Continuous Maritime Monitoring with SAR Ship Detection Time Series
SAR-based ship detection from Sentinel-1 provides vessel counts for any ocean area, updated every 6–12 days. Learn how continuous maritime monitoring reveals port activity, fishing effort, traffic patterns, and anomalies without AIS data dependency.
2026-03-29 · 11 min read
SAR Backscatter Time Series: Detecting Change with All-Weather Radar
Sentinel-1 SAR backscatter time series detects land surface changes regardless of cloud cover or daylight. Learn how VV, VH intensity, RVI, RFDI, and Cross Ratio respond to flooding, deforestation, vegetation growth, and construction events.
2026-03-26 · 7 min read
How to Monitor Any Area with Satellite Time Series: A Complete Guide
Area monitoring with satellite time series lets you automatically track changes in any region over weeks, months, or years. Learn how to set up a monitoring zone, choose the right index, and interpret results using Sentinel-1, Sentinel-2, and VIIRS data.
2026-03-19 · 11 min read
VV, VH, HH, HV: SAR Polarization Demystified
SAR polarization modes determine what you see in radar imagery. This post explains the physics behind polarization, why Sentinel-1 uses VV and VH, and how to choose the right polarization for your application.
2026-01-31 · 6 min read
SAR-Optical Data Fusion: Getting More from Two Sensors Than Either Alone
How to combine SAR radar and optical satellite imagery for better land cover mapping, change detection, and cloud-gap filling. Covers pixel-level, feature-level, and decision-level fusion approaches.
2026-01-09 · 10 min read
How to Read a SAR Image: What Bright and Dark Actually Mean
SAR images look nothing like photographs. This practical guide explains what creates bright and dark areas in radar imagery, common patterns you'll encounter, and how to avoid misinterpretation.
2025-12-18 · 6 min read
Mapping Floods with SAR: A Practical Workflow from Search to Analysis
Step-by-step guide to delineating flood extent using Sentinel-1 SAR data. Covers pre-event baseline selection, backscatter thresholding, and common interpretation mistakes to avoid.
2025-12-10 · 7 min read
Why SAR Can See Through Clouds (And Why That Matters More Than You Think)
Most people know SAR works through clouds, but few understand the physics behind it. This post explains the relationship between wavelength, atmospheric scattering, and why microwave frequencies pass through weather that blocks optical sensors.
2025-11-28 · 5 min read
Getting Started with Sentinel-1 SAR Imagery: A Beginner's Guide
Learn how to access and analyze Sentinel-1 SAR radar data in your browser. This step-by-step guide covers the basics of SAR imagery, how to search for data, and interpret your first radar image.
2025-11-12 · 7 min read
Sentinel-1 GRD vs RTC: Which SAR Product Should You Use?
Sentinel-1 data comes in multiple processing levels. GRD is the standard product, while RTC corrects for terrain effects. This guide explains the differences and when each product is the right choice.
2025-07-31 · 6 min read
Multi-Temporal SAR Color Composites: See Change in a Single Image
Assigning different dates to RGB channels creates a single color image where changes pop out in vivid colors. This technique turns SAR's temporal dimension into an intuitive visual tool.
2025-07-08 · 5 min read