Sentinel-1 · Copernicus · GEE

Turn satellite data into water security

We translate free Copernicus SAR imagery into actionable soil moisture maps, pump scheduling plans, and persistent moisture zone audits — for farmers, NGOs, and research institutions operating in semi-arid landscapes.

202
SAR acquisitions analysed
5yr
Time series coverage
39.5%
Field capacity (VSM)
30.3%
Plant available water
10m
Pixel resolution
23%
Field area in PMRZ

From satellite to field decision

We take freely available Copernicus data and convert it into practical water management tools your team can act on — no specialist software required.

01

Satellite data ingestion

Sentinel-1 IW GRD VV+VH imagery sourced from the free Copernicus Data Space, covering your site across multiple wet and dry seasons.

02

VSM estimation

VH gamma0 backscatter is log-transformed and normalised via the Change Detection Index (Wagner 1999), scaled to volumetric soil moisture (m³/m³).

03

FC & PWP derivation

Field capacity (P90 VSM) and permanent wilting point (P10 VSM) are derived empirically from the full 5-year distribution — no lab samples required.

04

PMRZ mapping

Pixels maintaining VSM above PWP in ≥80% of dry-season acquisitions are classified as Persistent Moisture Retention Zones — your water harvesting targets.

05

Report & ICT delivery

Georeferenced maps, methodology reports, Copernicus EO Browser scripts, and SMS alert systems are packaged and handed over — ready to use the same day.

Six consulting products

Each product is scoped, priced on enquiry, and delivered with a document report plus an ICT digital component. Mix and match for your project budget.

ASC-001 Starter

Field Water Balance Audit

5-year Sentinel-1 SAR analysis delivered as a PDF report: VSM estimates, FC/PWP thresholds, seasonal risk calendar, and a GEE monitoring script.

  • 5-year Sentinel-1 soil moisture time series
  • Field capacity and PWP derivation
  • Seasonal pump scheduling risk calendar
  • GEE monitoring script handover
  • SMS alert setup guide included
ASC-002 Mapping

PMRZ Mapping Service

Satellite-derived spatial mapping of Persistent Moisture Retention Zones — GeoTIFF map, Word methodology report, three Copernicus EO Browser scripts.

  • Georeferenced PMRZ map (GeoTIFF + PNG)
  • 3 custom Copernicus EO Browser scripts
  • Temporal Exceedance Frequency analysis
  • GEE automation script for monitoring
  • SMS drought alert thresholds configured
ASC-003 Package

Climate-Smart Irrigation Scheduling

End-to-end precision water management: safe extraction volumes, optimal rest intervals, seasonal risk windows, and an ICT dashboard prototype with GEE integration.

  • Bespoke pump scheduling calendar
  • Water balance zone map
  • Scenario A vs B failure analysis
  • ICT dashboard prototype + GEE backend
  • Peer-review ready methodology report
ASC-004 Training

Capacity Building Workshop — 1 Day

Hands-on training in Sentinel-1 SAR, EO Browser scripting, GEE basics, and NDMI threshold setting. Online or in-person, up to 20 participants.

  • Full-day online or in-person delivery
  • 3 working EO Browser scripts per participant
  • GEE starter project set up live
  • 40-page printed + digital reference guide
  • Certificate of participation issued
ASC-006 Digital

Google Merchant Center Product Feed Setup

Done-for-you GMC feed setup for consulting firms and NGOs. Taxonomy design, feed creation, all attribute population, image spec guide, and upload-ready CSV.

  • Upload-ready CSV, all attributes populated
  • Up to 10 products structured and listed
  • Product highlights + detail attributes
  • Image specification checklist
  • 30-minute Zoom handover call

Why timing matters more than volume

The same 2,600 litres produces opposite outcomes depending entirely on whether the pump schedule is synchronised with the aquifer's natural recharge rhythm.

Scenario A — The Rush

Pump 2,600 L in one go

The well runs dry in 50 minutes. Lateral inflow from the regional aquifer (≈120 L/hr through 15 m of fractured rock) cannot compensate for the extraction rate of ≈52 L/min. The pump sucks air.

Remote sensing identifies these water stress windows — the 6.9% of acquisitions where VSM drops below PWP — before they cause borehole damage.

Scenario B — The Rhythm

3 sessions with 8-hour rests

The same 2,600 L is extracted safely across three sessions. Each 8-hour rest period exceeds the 2-hour recharge travel time by 4×, allowing near-complete aquifer recovery between sessions.

Satellite VSM data identifies the recharge surplus windows — the 17.8% of acquisitions where VSM exceeds FC — that define the optimal rest-period scheduling calendar.

✓  Well sustains indefinitely — reliable water source

Field Water Balance — governing equation

P + I + Cin − (ETc + R + D + Cout) = ΔS

ΔS
Change in storage — quantified by Sentinel-1 SAR at each 6-day overpass
ETc
Pump extraction / crop evapotranspiration — the variable we schedule
I
Infiltration — recharge from soak pits, mapped as PMRZ surplus zones
Cin
Lateral groundwater inflow — the 2-hour travel path through fractured rock
P
Precipitation — correlated with ERA5 Land daily rainfall data
R, D
Runoff and deep drainage — residual terms estimated from VSM trends
39.5%
m³/m³ VSM
Field Capacity (FC)
P90 of 5-year SAR record. Moisture retained after gravity drainage — the upper safe storage limit.
0%43% (porosity)
9.2%
m³/m³ VSM
Permanent Wilting Point (PWP)
P10 of 5-year SAR record. Below this threshold plants cannot extract water — stress zone.
0%43% (porosity)
30.3%
m³/m³ PAW
Plant Available Water
FC minus PWP. Equates to 90.9 mm per 0.3 m root zone — 8–25 days of crop water supply.
0%43% (porosity)
23.9%
m³/m³ VSM
Long-term Field Mean
5-year average across 202 acquisitions. Trending upward: +0.057 m³/m³ since 2021.
0%43% (porosity)

How we derive soil moisture from radar

Our analysis pipeline is fully reproducible using free tools — Google Earth Engine, QGIS, and Python. We hand over all code on delivery.

01

Log-transform VH gamma0 backscatter

Linear VH values from Sentinel-1 IW GRD are converted to decibels: VH_dB = 10 × log₁₀(VH_linear). Site values range −17.2 to −12.0 dB — the 5.2 dB dynamic range encoding the full wet-dry moisture cycle.

VH_dB · Sentinel-1 IW GRD
02

Apply the Change Detection Index (CDI)

Relative soil moisture: ms(t) = [VH_dB(t) − VH_dry] / [VH_wet − VH_dry]. Dry anchor: P5 of 5-yr VH (−16.4 dB). Wet anchor: P95 (−13.1 dB). Result: 0–1 wetness index.

Wagner et al. 1999 · CDI
03

Scale to volumetric soil moisture (VSM)

The wetness index is scaled using soil porosity and residual moisture: VSM = θr + ms × (φ − θr) where φ = 0.43 and θr = 0.07 for loam (Saxton & Rawls 2006).

VSM m³/m³ · loam texture
04

Derive FC and PWP from percentile anchors

Field Capacity = P90 VSM across the full 5-year record (0.395 m³/m³). Permanent Wilting Point = P10 VSM (0.092 m³/m³). This empirical approach avoids uncertainty from pedotransfer functions on poorly characterised semi-arid soils.

FC = P90 · PWP = P10 · PAW = FC − PWP
05

Classify pixels into water balance zones

Each acquisition is zoned: surplus (VSM > FC, 17.8%), plant-available (PWP ≤ VSM ≤ FC, 75.2%), and water stress (VSM < PWP, 6.9%). Stress-zone dates trigger the Scenario A failure risk SMS alert.

3-zone classification · SMS integration
06

Delineate Persistent Moisture Retention Zones

Pixels with Temporal Exceedance Frequency ≥ 0.80 (VSM > PWP in ≥80% of dry-season acquisitions) are mapped as PMRZs. These zones occupy ~23% of the study field and cluster at footslope positions and near soak pit structures.

TEF ≥ 0.80 · PMRZ · GeoTIFF output

Built for decision-makers on the ground

Our products are scoped for four distinct client types — each with a different starting point, budget, and delivery requirement.

Smallholder farmers & cooperatives

Practical tools to prevent borehole failure, extend the growing season, and identify the most reliable spots on the farm for dry-season crops.

  • ASC-001 Starter Audit (entry point)
  • SMS water stress alerts
  • Pump scheduling calendar

NGOs & development organisations

Evidence-based hydrological audits for water point design, community irrigation schemes, and grant reporting with academic-quality references.

  • ASC-002 PMRZ mapping for site selection
  • ASC-005 Full recharge assessment
  • Grant-ready research reports

Government & policy agencies

Landscape-scale aquifer recharge assessments suitable for national water policy, climate adaptation planning, and infrastructure investment decisions.

  • ASC-005 Flagship full site study
  • Policy brief + evidence base package
  • Multi-site scoping available

Research institutions & universities

Reproducible SAR soil moisture pipelines, dataset access, co-authorship collaborations, and capacity building workshops for postgraduate cohorts.

  • ASC-004 Workshop for research teams
  • GEE script and dataset handover
  • Co-authorship and review collaboration

Ready to see your field's moisture map?

Send us your site coordinates, approximate field area, and the question you need answered. We'll respond within 2 working days with a scoped proposal.

Send an enquiry