01 · FROM ORBIT
Observe the living Earth
NISAR radar measures changing surfaces through day and night.
KUNTAU TERRAPULSE
Data stays on this device
EARTH OBSERVATION WORKSPACE
See beyond the
surface.
A focused Earth-observation studio for comparing real NISAR radar measurements and investigating changes around river corridors.
02 · ALONG THE RIVER
Observe river corridors
Compare radar responses around channels and floodplains, then verify on the ground.
03 · FOR COMMUNITIES
Support local investigation
Give communities and response teams clearer places to check after changing conditions.
YOUR CURRENT WORKSPACE
Study at a glance
OBSERVATIONS LOADED
0 / 2
Load your original NISAR GeoTIFFs to begin
STUDY FOOTPRINT
Kura test AOI
A study rectangle, not a verified river or floodplain boundary
8.4003°–8.4603° E
OBSERVATION WINDOW
12 days
8 Oct → 20 Oct 2026 · UTC acquisition dates
NISAR · L-band · GCOV
NEXT STEP
Bring in your observations
Select the original October 8 and October 20 GeoTIFFs. They are read locally; nothing is uploaded to a server.
TIF
Before · 8 October 2026Kura_Before_2026-10-08.tif
WaitingTIF
After · 20 October 2026Kura_After_2026-10-20.tif
WaitingSCIENTIFIC INTEGRITY
Evidence before interpretation
Measurements are not diagnoses
Radar backscatter can respond to water, wet soil, vegetation, surface roughness and acquisition conditions. A change alone does not prove flooding.
Polarization configuration differs
The October products are SHSH and DHDH. We will flag this when assessing comparability.
✳ Built by KUNTAU Science Academy · NASA Space Apps Challenge 2026 · “Dancing with the SARs”
GEOGRAPHIC CONTEXT
Explore the study area.
Locate the Kura test footprint and inspect any locally loaded NISAR observation.
Kura · Kano State
ⓘ Change colours show relative increases/decreases in the selected radar measurement for this pair only. They are not a water mask or flood classification. The outlined rectangle is the analysis area used for the initial data extraction. It is not a surveyed river centreline, floodplain boundary or property boundary. The exact intersection with the Rafin Kura channel must be verified. Basemap tiles require an internet connection.
TWO-DATE ANALYSIS
Compare what changed.
Load the original NISAR GeoTIFFs from your computer. This browser reads them locally.
Scientific comparability check required
The October 8 scene is SHSH (HH single-polarization); October 20 is DHDH (HH/HV dual-polarization). We use the shared HHHH measurement layer, but the different acquisition modes must be considered before interpreting differences.
No observations loaded yet. Select both original .tif files to enable comparison.
VISUAL COMPARISON
Before / after viewer
◎
Your evidence will appear hereLoad both original GeoTIFFs. The app will check their grids before calculating a pixel-wise difference.
08 OCT · BEFORE
20 OCT · AFTER
AFTER − BEFORE · EXPLORATORY
Earlier observation Later observationDisplay stretch is for visualisation only.
VALID PIXELS—
MEAN Δ—
POSITIVE Δ—
NEGATIVE Δ—
Exploratory radar-response differences only — not a water mask, river-level measurement or flood forecast.
INTERPRETATION, WITH CAUTION
Turn signals into understanding.
A radar measurement can reveal surface change. It cannot, by itself, measure river depth, flow rate or water level.
No validated analysis yet
Load both original observations in Compare. The app will then show measurement summaries and clearly separate measured differences from possible river or floodplain explanations.
WHAT RADAR MEASURES
Backscatter response
GCOV provides calibrated, terrain-corrected radar covariance measurements. The values respond to surface and structural properties, moisture, geometry and other factors.
NISAR GCOV guide ↗WHAT CHANGE CAN MEAN
Several possible drivers
Changes can be associated with open water, wet soil, floodplain vegetation, roughness or acquisition conditions. Independent evidence is needed to distinguish them.
WHAT WE MUST NOT CLAIM
No automatic flood prediction
Do not infer river depth, flow speed, water level or future flood risk from this two-date radar comparison alone.
NEXT EVIDENCE TO ADD
Connect radar signals to river evidence
For stronger interpretation, combine radar with river-gauge readings, rainfall records, flood reports, field photographs and community observations.
REPRODUCIBILITY & SOURCES
Know where the evidence comes from.
Product identifiers, processing context and limitations belong alongside every map. Download this catalogue now; file-specific statistics are added after the GeoTIFFs load.
PROCESSING RECORD
Current extraction settings
Science productNISAR GCOV · Provisional · L-band
Selected datasetFrequency A / HHHH
Study locationKura test AOI · Kano, Nigeria
Expected CRS / spacingEPSG:32632 · 20 m
Raster dimensions327 × 332 pixels
Extraction toolGDAL · gdalwarp
Before / after gridSame origin, extent and pixel spacing (reported)
Data maturityProvisional
Important: The app re-checks the files you load. The values above are the extraction details reported during the initial processing; they are not treated as independently verified metadata until the source files are examined.
OFFICIAL REFERENCES
ASF NISAR GCOV Data User GuideProduct structure, covariance layers and polarization codesAlaska Satellite Facility — SearchOriginal NISAR data discovery and product recordsLocal reporting: River Kura impactsContext for the Kura-area river and floodplain use case; not a validation of this AOIOpenStreetMap attributionBasemap contributors and usage information PERSONALISE YOUR WORKSPACE
Make it yours.
Choose how KUNTAU TERRAPULSE looks and behaves on this device.
APPEARANCE
Choose your theme
Your choice is saved in this browser and stays local to this device.
LOCAL DATA & PRIVACY
Your satellite files stay with you
The app reads the GeoTIFF files you select inside Chrome. It does not automatically upload them to a server. Refreshing the page clears the current in-memory raster session, so keep your original files safe.
AuthenticationNot required
Raster processingIn this browser session
Source data locationYour computer
FIRST-RUN EXPERIENCE
Replay the introduction
Show the five welcome screens again, including the project story and how the comparison works.
VISUAL CREDITS
Images used in this workspace
These are illustrative editorial images, not the Kura GeoTIFF observations and not evidence of conditions inside the test AOI.
NISAR orbit visual: NASA Scientific Visualization Studio, “NISAR satellite orbit”.
Nigerian farmland: Abeltrust / Wikimedia Commons · CC BY-SA 4.0.
Nigerian field photograph: mk_photoz / Pexels · Free to use.
KUNTAU TERRAPULSEVersion 0.5.0 · KTP Space StudioBuilt by KUNTAU Science Academy · Kano Local Event