One community survey, checked against the regional model and the 2017 map. A record you can verify, read, and act on.
Site Acciaroli to Pioppi, Cilento (IT)Outing 2026-07-02Habitat Posidonia oceanica, living (ISPRA A5.535)Surveyed by Island Lab field kit + snorkel leg
The finding
Three ways of knowing the same water, side by side. The regional model reads the basin; our sensors read the meadow at depth.
Realtime model
Regional climatology
25.7°C
synthetic Basin-scale seasonal norm (Copernicus / EU DTO class). Too coarse to see this meadow.
Regional survey
ISPRA seabed map, 2017
living
open data EMODnet / ISPRA, EUNIS A5.535. Tells us where the meadow is, not today's stress.
Local sensor
Our meadow reads, today
27.2°C
measured 11 curated water reads, GPS-confirmed over the meadow.
The meadow is +1.5 °C warmer than the regional model shows.
WATCH
28 °C stress onset
30 °C
model 25.7
measured 27.2
The uncorrected regional model reads 25.7 °C, which looks safe. Our sensors, in the meadow, measured
27.2 °C, only 0.8 °C below the 28 °C threshold where Posidonia oceanica
begins heat stress. That gap between "the model says safe" and "the meadow is close" is exactly the value of local sensing.
Live nowcast SST: fetching…
Why you can trust this number
Every reading is traceable from the device to the finding. This chain is what turns a snorkel outing into evidence a credit auditor, or a mayor, can stand behind.
1
Raw device readings
Full export off the field kit, on-device capture time recorded (not just sync time)
33 rows
2
Drop out-of-water and bad reads
Remove air and bad labels: only in-water temperatures count
17 water
3
Keep only reads inside the meadow
Point-in-polygon against the ISPRA A5.535 extent open
GPS ✓
4
Curated meadow mean
GPS-confirmed, over living Posidonia, single outing (day-of-year 183) measured
27.2 °C
Reference: France's Label Bas-Carbone blue-carbon standard grades credit value by data quality, Tier 1 satellite to Tier 3 dynamic accounting of whether protection is working. A curated, GPS-confirmed in-meadow measurement is the community's on-ramp to that ladder.
Did this survey change what we know?
Yes. Feeding these reads into the local twin (Proteus) raised its confidence in the meadow's temperature. The community's measurement measurably improved the model.
Twin confidence before 0.24after this outing 0.40(+0.15)
Where confidence is still low, the twin tells us what to measure next: at the deeper, light-limited edge of the meadow the dominant unknown is light, not temperature. The recommended next reading is an optical sensor (PAR-at-depth and turbidity) below roughly 35 m. That is the next community outing, chosen by the data.
What it means, and for whom
For the mayor
A meadow worth roughly €92.6M/year in ecosystem services (Pollica coast, 1,077 ha) is running within 1 °C of heat stress. This is the evidence line for an enforcement or monitoring decision.
For the student
Your snorkel reads are in the record. You changed the model. The next outing the data is asking for is yours to run.
For the fisher
The nursery your catch depends on is under measurable thermal pressure this summer, and now there is a local number to point to, not just a bad season.
For the record
One verified outing. Repeat it through the summer and the trend, better or worse, becomes the community's own defensible dataset.