Normalized Burn Ratio (NBR & $\Delta NBR$) mathematical engine (`nbr-calculator.ts`) #70

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opened 2026-10-14 22:28:42 +00:00 by yuris · 0 comments

yuris commented

2026-10-14 22:28:42 +00:00

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What to build

Implement post-fire burn severity calculation using Normalized Burn Ratio (NBR = rac{NIR - SWIR}{NIR + SWIR}) and \Delta NBR = NBR_{pre} - NBR_{post} in src/lib/gis/nbr-calculator.ts.

Technical specifications

Target files:
- src/lib/gis/nbr-calculator.ts: Mathematical calculation functions.
- src/lib/gis/__tests__/nbr-calculator.test.ts: Unit test suite with USGS benchmark values.
Classification levels:
- High Severity: \Delta NBR > 0.66.
- Moderate Severity: 0.27 < \Delta NBR \leq 0.66.
- Low Severity: \Delta NBR \leq 0.27.

Acceptance criteria

Formulas output exact float values matching USGS standards.
Unit tests pass with zero NaN / divide-by-zero errors.

Authoritative Specifications & Reference Documentation

Titik Gambut Architecture & Subsystem Contract: docs/ARCHITECTURE.md
Copernicus Sentinel-2 STAC API: Earth Search STAC API — AWS Element84 Sentinel-2 L2A STAC catalog.
Normalized Burn Ratio (NBR) Standard: USGS Landsat NBR — Formula: (B8 - B12) / (B8 + B12).
European Forest Fire Information System (EFFIS): EFFIS Burn Severity Classification — Delta-NBR fire damage scoring.

### What to build Implement post-fire burn severity calculation using Normalized Burn Ratio ($NBR = rac{NIR - SWIR}{NIR + SWIR}$) and $\Delta NBR = NBR_{pre} - NBR_{post}$ in `src/lib/gis/nbr-calculator.ts`. ### Technical specifications 1. **Target files**: - `src/lib/gis/nbr-calculator.ts`: Mathematical calculation functions. - `src/lib/gis/__tests__/nbr-calculator.test.ts`: Unit test suite with USGS benchmark values. 2. **Classification levels**: - High Severity: $\Delta NBR > 0.66$. - Moderate Severity: $0.27 < \Delta NBR \leq 0.66$. - Low Severity: $\Delta NBR \leq 0.27$. ### Acceptance criteria - [ ] Formulas output exact float values matching USGS standards. - [ ] Unit tests pass with zero NaN / divide-by-zero errors. --- ### Authoritative Specifications & Reference Documentation - **Titik Gambut Architecture & Subsystem Contract**: [`docs/ARCHITECTURE.md`](https://git.nokopia.com/yuris/titik-gambut-next/src/branch/main/docs/ARCHITECTURE.md) - **Copernicus Sentinel-2 STAC API**: [Earth Search STAC API](https://earth-search.aws.element84.com/v1) — AWS Element84 Sentinel-2 L2A STAC catalog. - **Normalized Burn Ratio (NBR) Standard**: [USGS Landsat NBR](https://www.usgs.gov/landsat-missions/normalized-burn-ratio) — Formula: $(B8 - B12) / (B8 + B12)$. - **European Forest Fire Information System (EFFIS)**: [EFFIS Burn Severity Classification](https://effis.jrc.ec.europa.eu/) — Delta-NBR fire damage scoring.

yuris added this to the Satellite Imagery & Burn Perimeters Pipelines (Backend) milestone

2026-10-14 22:28:42 +00:00

yuris added the

backend

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2026-10-14 22:28:42 +00:00

yuris changed title from ~~Issue 57: [Backend] Normalized Burn Ratio (NBR & $\Delta NBR$) mathematical engine (nbr-calculator.ts)~~ to [Backend] Normalized Burn Ratio (NBR & $\Delta NBR$) mathematical engine (nbr-calculator.ts)

2026-10-14 22:31:24 +00:00

yuris changed title from ~~[Backend] Normalized Burn Ratio (NBR & $\Delta NBR$) mathematical engine (nbr-calculator.ts)~~ to Normalized Burn Ratio (NBR & $\Delta NBR$) mathematical engine (nbr-calculator.ts)

2026-10-14 22:38:30 +00:00

yuris referenced this issue from a commit

2026-10-15 04:57:06 +00:00

feat(gis): implement Normalized Burn Ratio (NBR) and Delta NBR engine (#70)

yuris referenced this issue

2026-10-15 04:57:13 +00:00

feat(gis): implement Normalized Burn Ratio (NBR) and Delta NBR engine (#70) #117

yuris referenced this issue from a commit

2026-10-15 05:06:02 +00:00

feat(gis): implement Normalized Burn Ratio (NBR) and Delta NBR engine (#70) (#117)

yuris closed this issue

2026-10-15 05:06:08 +00:00