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Scientific · Sector explainer
Field campaigns, seismology, hydrology, ocean, ecology, polar and research-infrastructure gap filling. Six scenes, each a working calculation: the cost of a valid data-year, earthquake warning time at a school, a stream-gauge rating curve, wave physics at a buoy, a recorder’s storage and listening range, and the radio horizon of a quiet site.
01 · Gap-filling nodes
Scenario
Observatory-as-a-service for research infrastructures that must extend coverage under their own quality rules. The number that matters to a research infrastructure is the cost of one valid year of data: the capital cost spread over the service life plus the running cost, divided by the share of the year the record passes quality control. Coverage follows from spacing: a square lattice of spacing s needs area / s² nodes, and the mean distance from any point to its nearest node is 0.383 s.
02 · School seismographs
Scenario
Compact seismographs feeding open data networks. In a typical crust the P wave travels at about 6.0 km/s and the damaging S wave at about 3.5 km/s. Each second between them puts the source about 8.4 km away, Vp·Vs/(Vp − Vs). Warning time at the school is the S-wave arrival less the time the nearest station needs to see the P wave and issue the alert; inside the blind zone, the shaking arrives first.
03 · Stream gauges
Scenario
A low-cost tier beside national gauge networks. A gauge reads water level; discharge comes from the site’s rating curve, Q = a (h − h₀)b, fitted to current-meter or ADCP gaugings. The exponent sets how stage error turns into flow error: a stage error δh gives a relative flow error of about b · δh / (h − h₀), which is why low flows need the most careful level sensor.
04 · Wave buoys
Scenario
A low-cost wave buoy measures heave and reports significant height and period over satellite. Linear wave theory turns those into what engineers need: the dispersion relation ω² = g k tanh(k d) gives the wavelength at any depth (gT²/2π in deep water), and the energy flux per metre of crest is ρ g H² cg / 16, about 0.49 H² T kW/m in deep water. A short-burst satellite message carries up to 340 bytes.
05 · Bioacoustics
Scenario
Open acoustic recorders for species baselines. Storage is sample rate times bit depth times the fraction of the day the recorder is on; the highest frequency recorded is half the sample rate, so bats need far more storage than birds. Listening range follows spherical spreading: a call is heard while its source level less 20 log r stays above the ambient noise by the detector’s required signal-to-noise ratio. Air absorption and foliage shorten it further, most of all above 10 kHz.
Sample rate
Bit depth
Memory card
06 · Polar and quiet sites
Scenario
Autonomous stations with satellite backhaul in harsh environments. For a radio telescope the question is interference. Free-space loss, 20 log d + 20 log f + 32.44, is far too weak on its own: the distance it would take to bring a modest transmitter below a radio-astronomy protection level runs to hundreds of thousands of kilometres. What protects a site is the horizon and the terrain. With standard refraction the radio horizon between two antennas is about 4.12 (√h₁ + √h₂) km, heights in metres; a transmitter beyond it reaches the dish only by diffraction and scatter.
Observing frequency
07 · Proof
Evidence
Research infrastructures accept a station when its data can be traced, read and cited. The grid keeps each piece of that evidence as a record beside the station it describes.
Show the record for
—Proof
The grid produces each item as a record with the data it supports, not a report written afterwards.
01Calibration traceability
02data-format conformance (netCDF/CF, FDSN, OGC SensorThings, WIS2)
03datasets with persistent identifiers
04uptime in harsh environments
05cost per data-year
Tell us the site, the sector and what you need to observe. We bring the survey, the design and the crew.
Talk to usSector overview