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
- +1. Ocean colour (hyperspectral)1 datasets
- +1. Ocean colour (merged)3 datasets
- +1. Ocean colour (single sensor)5 datasets
- −2. Inland/coastal high-res6 datasets
- ·AL03 · Sentinel-2 MSI Level-2A (harmonised)A+ Gold10 m (B2,3,4,8) / 20 m (B5 red-edge 705 nm) · 5 days (2-3 d with S2… · 2015-06 (L1C) / 2017-03 (L2A)→present
- ·AL04 · Sentinel-3 OLCI — 21 bands incl. 620 nm (phyc…A+ Gold300 m full resolution · ~1-2 days (S3A + S3B) · 2016-10→present
- ·AL05 · Landsat 5 / 7 / 8 / 9 Collection 2 Level-2A+ Gold30 m · 16 days per satellite… · 1984 (L5) / 1999 (L7) / 2013 (L8→present
- ·AL14 · Harmonized Landsat Sentinel-2 (HLS) v2.0B Usable30 m · 2-3 days combined · 2013 (L30) / 2015 (S30)→present
- ·AL16 · MODIS MOD09GA/GQ daily surface reflectance (2…B Usable250 m (b1,b2) / 500 m · DAILY · 2000-02-24→present
- ·AL18 · Sentinel-2 Level-1C + ACOLITE Dark Spectrum F…B Usable10-20 m · 5 days · 2015-06→present
- +3. Lake / inland operational2 datasets
- +4. Model / reanalysis1 datasets
- +5. Discovery / portal1 datasets
- +6. Derived / uncalibrated2 datasets
- +7. In-situ validation5 datasets
- −SITE-WISEwhat actually applies at each site
- −Chakaria HDSSChakariaRural COASTAL · 10 km to sea · 16 datasets apply
- ·AL01 · ESA Ocean Colour CCI v6.0 — merged multi-se…Daily / 5-day / 8-day / M… · 4 km (1 km regional available)
- ·AL02 · Copernicus Marine GlobColour — L4 gap-free …DAILY (gap-free!) · 4 km
- ·AL11 · Copernicus CDS — Satellite Ocean Colour (OC…Daily / monthly · 4 km
- ·AL06 · MODIS-Aqua Level-3 SMIDaily / 8-day / monthly · 4.6 km
- ·AL07 · SeaWiFS Level-3 SMIDaily / 8-day / monthly · 9 km (4 km avail.)
- ·AL08 · VIIRS SNPP / NOAA-20 chlorophyll (NOAA Coas…DAILY · 4 km (750 m for some SNPP products)
- ·AL13 · MODIS-Terra Level-3 SMIDaily / 8-day / monthly · 4.6 km
- ·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
- ·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
- ·AL23 · GLORIA — Global Reflectance community datas…Per sample · Point
- ·AL25 · Bangladesh Oceanographic Research Institute…Varies · Point
- −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
- ·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)
- ·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
- ·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
- ·AL24 · LIMNADES — LIMnology and remote sensing Net…Per sample · Point
- −Chakaria HDSSChakariaRural COASTAL · 10 km to sea · 16 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
2. Inland/coastal high-res
AL05 · Landsat 5 / 7 / 8 / 9 Collection 2 Level-2
USGS / NASA
A+ Gold
FREE
NO ACCOUNT
Source · duration · capture cadence
- Data source
- USGS / NASA
- Access route
- GEE · USGS M2M API · AWS Open Data S3
- Endpoint / asset
LANDSAT/LT05|LE07|LC08|LC09/C02/T1_L2 | m2m.cr.usgs.gov/api- Duration
- 1984 (L5) / 1999 (L7) / 2013 (L8 → present
- Capture cadence
- 16 days per satellite (~8 d with two in orbit)
- Resolution
30 m- Delivers
- Chlorophyll proxy (green/blue, needs local calibration), FAI, turbidity, MNDWI, water surface temperature
- Command
10_algae_daily_3sites.py --sensors landsat
Why it is used for cholera.
Well validated for land · water-quality retrieval requires LOCAL calibration
Why not — catalogue limitation. NO RED-EDGE BAND → true NDCI is impossible. This is the weakest link in your 2000-2015 record. Get Sarker et al. 2019 (Front. Mar. Sci. 6:598) for Bangladeshi coefficients. L7 SLC-off stripes after 2003-05-31.
Site applicability
| Site | Verdict | Why |
|---|---|---|
| Chakaria HDSS | YES | ESSENTIAL for 2000-2015 |
| Matlab HDSS | YES | ESSENTIAL for 2000-2015 |
| Dhaka City | YES | ESSENTIAL for 2000-2015 |
Reliable · accessible · authentic
A+ Gold
Reliability tier
OPEN
Accessible
USGS
Authentic — operator
Typed limitations (3)
HIGH 16-day revisit misses short blooms entirely temporal
One Landsat satellite passes every 16 days. A bloom that initiates, peaks and collapses inside two weeks can fall entirely between two passes and leave no trace in the record.
What to do: Two satellites in orbit halve the effective interval to about 8 days. Combine L7+L5 for 2000-2012 and L8+L9 for 2021 onward. Report bloom FREQUENCY with an explicit detection-probability caveat.
HIGH Landsat 7 SLC-off stripes after May 2003 coverage
The scan-line corrector failed in 2003, leaving wedge-shaped data gaps that widen toward the scene edge and lose roughly 22 percent of each image.
What to do: Mask the gaps rather than gap-filling them, and record the usable water-pixel count per pass. The water_px column already does this.
HIGH No red-edge band, so no NDCI spectral
Landsat has no band near 705 nm. The green/blue ratio used instead is the open-ocean approach and is known to fail in turbid productive water - which is every water body in this study.
What to do: Treat the Landsat chlorophyll series as a RELATIVE index only, and never splice it to a Sentinel-2 NDCI series without the bias correction in 11_algae_daily_fill.py.