Network panel
Algae Dataset
Every data hub, dataset, sensor, variable, paper and limitation in one tree — and for each: where it comes from, how far back it goes, how often it captures, why it belongs in a cholera study, and why it does not work everywhere.
Highlight site
All three
Chakaria HDSS
Matlab HDSS
Dhaka City
Choosing a site greys out everything that does not apply there.
- +DATA HUBSwhere the data physically comes from
- +DATASET TYPESgrouped by what kind of water they see
- −SITE-WISEwhat actually applies at each site
- +Chakaria HDSSChakariaRural COASTAL · 10 km to sea · 16 datasets apply
- −Matlab HDSSMatlabRural riverine · 250 km to sea · 11 datasets apply
- ·AL03 · Sentinel-2 MSI Level-2A (harmonised)5 days (2-3 d with S2C fr… · 10 m (B2,3,4,8) / 20 m (B5 red-edge 705 nm)
- ·AL04 · Sentinel-3 OLCI — 21 bands incl. 620 nm (ph…~1-2 days (S3A + S3B) · 300 m full resolution
- ·AL05 · Landsat 5 / 7 / 8 / 9 Collection 2 Level-216 days per satellite (~8… · 30 m
- ·AL14 · Harmonized Landsat Sentinel-2 (HLS) v2.02-3 days combined · 30 m
- ·AL16 · MODIS MOD09GA/GQ daily surface reflectance …DAILY · 250 m (b1,b2) / 500 m
- ·AL18 · Sentinel-2 Level-1C + ACOLITE Dark Spectrum…5 days · 10-20 m
- ·AL19 · GEE Sen2Cor L2A NDCI → chlorophyll polynomi…5 days · 10-20 m
- ·AL20 · Landsat green/blue chlorophyll proxy (2000-…16 days · 30 m
- ·AL22 · SeaBASS — NASA bio-Optical Archive and Stor…Per cruise/campaign · Point
- ·AL23 · GLORIA — Global Reflectance community datas…Per sample · Point
- ·AL26 · icddr,b environmental microbiology archives…FORTNIGHTLY · Point (pond)
- +Dhaka CityDhakaUrban inland · 300 km to sea · 9 datasets apply
- +DURATION & CAPTURE CADENCEdaily · weekly · 10-day · 16-day · monthly
- +VARIABLESwhat is computed from the bands
- +LIMITATIONSwhy not — typed and severity-ranked
- +PAPERSthe evidence, DOI-linked
Site
Matlab HDSS
Rural riverine ·
23.39130 N, 90.70120 E · 20.4 x 22.1 km ·
250 km to the Bay of Bengal
- Water bodies
- Meghna river (2-6 km wide), Dhonagoda river, Gumti, canals, beels, thousands of household ponds
- Trophic state
- Meso- to eutrophic. Agricultural nutrient runoff · high suspended sediment.
- Algae regime
- MIXED. The Meghna is wide enough for 250-300 m sensors, so both the regional river-plume signal and local pond blooms are observable.
- Ocean colour
- REGIONAL FORCING ONLY — reg_ prefix
11
datasets apply
11
partial
4
not applicable
What works here
| Dataset | Cadence | Duration | Res | Why |
|---|---|---|---|---|
| AL03 Sentinel-2 MSI Level-2A (harmonised) | 5 days (2-3 d with S2C … | 2015-06 (L1C) / 2017-03 (L2A)→present | 10 m (B2,3,4,8) / 20 m (B5 red-edge 705 nm) |
HIGHEST VALUE — resolves individual village ponds and the Dhonagoda |
| AL04 Sentinel-3 OLCI — 21 bands incl. 620 nm… | ~1-2 days (S3A + S3B) | 2016-10→present | 300 m full resolution |
CRITICAL — the Meghna is 2-6 km wide, so 300 m works beautifully · near-daily revisit |
| AL05 Landsat 5 / 7 / 8 / 9 Collection 2 Leve… | 16 days per satellite (… | 1984 (L5) / 1999 (L7) / 2013 (L8→present | 30 m |
ESSENTIAL for 2000-2015 |
| AL14 Harmonized Landsat Sentinel-2 (HLS) v2.0 | 2-3 days combined | 2013 (L30) / 2015 (S30)→present | 30 m |
HIGH |
| AL16 MODIS MOD09GA/GQ daily surface reflecta… | DAILY | 2000-02-24→present | 250 m (b1,b2) / 500 m |
USEFUL — the Meghna is wide enough for 250 m, giving you a DAILY 2000-2026 bloom record |
| AL18 Sentinel-2 Level-1C + ACOLITE Dark Spec… | 5 days | 2015-06→present | 10-20 m |
THE RIGOROUS ROUTE for village ponds |
| AL19 GEE Sen2Cor L2A NDCI → chlorophyll poly… | 5 days | 2017-03→present | 10-20 m |
SCREENING ONLY |
| AL20 Landsat green/blue chlorophyll proxy (2… | 16 days | 1984→present | 30 m |
USE WITH EXPLICIT CAVEAT |
| AL22 SeaBASS — NASA bio-Optical Archive and … | Per cruise/campaign | 1980s→present | Point |
Unlikely to have inland Bangladesh data |
| AL23 GLORIA — Global Reflectance community d… | Per sample | 1980s→2021 | Point |
HIGH — includes turbid inland waters |
| AL26 icddr,b environmental microbiology arch… | FORTNIGHTLY | ~2000→varies | Point (pond) |
HIGHEST VALUE — Huq et al. 2005 sampled Matlab ponds fortnightly for 3 years |
What does NOT work here — and why
| Dataset | Reason |
|---|---|
| AL15 PACE OCI — hyperspectral 380-900 nm at … | LOW — 1.2 km |
| AL21 OCTS / CZCS historical ocean colour | LOW |
| AL10 ESA CCI Lakes v2.x | LOW — sub-kilometre water bodies |
| AL12 CMEMS Global Ocean Biogeochemistry Rean… | LOW — 28 km |
Site-specific problems
CRITICAL Matlab shapefile contains 43 polygons from another upazila spatial blocks Matlab
MATLAB_HDSS_AREA.shp holds 251 polygons across Matlab Uttar (112), Matlab Dakkhin (96) and Daudkandi (43). Daudkandi is in Cumilla district, outside the HDSS. 42 of those 43 sit in Block E, so extracting without filtering leaves Block E 56 percent contaminated with no matching population denominator.
What to do: Filter UPAZILA_NA != 'Daudkandi' - 208 polygons remain - and re-derive block membership. Block E falls from 75 polygons to 33. Upload the filtered file as the Earth Engine asset.
CRITICAL Matlab village ID key is effectively empty access blocks Matlab
The vid field is populated in 8 of 251 records, and 251 polygons carry only 245 distinct village names with six names used twice. Neither an ID join nor a name join to the HDSS outcome data is safe.
What to do: Request the village-ID lookup table from icddr,b. Until it arrives, model at BLOCK level - seven units - and extract at village level anyway so nothing has to be redone later.