Regional sea-level budgets
Tide gauge, altimetry and land motion data are combined to separate the causes of local sea-level change, so projections can be adjusted for each coast.
GCRI · Oceans and Coasts
Ocean science for coastal risk
Ocean and coastal science is the core science this platform stewards for the network. It explains how the ocean stores heat and carbon, how sea level, currents and waves change, and how these physical drivers shape coastal hazards and marine life.
01Contents
Ocean science for coastal risk in five parts.
02Application
What ocean and coastal science does here.
Ocean science studies the physics, chemistry, biology and geology of the oceans and coasts. It informs sea-level rise, storm surge, marine heatwaves, acidification and fisheries change, all of which affect coastal populations and trade. In oceans and coasts, climate and hazards and biodiversity and nature, ocean projections guide coastal defence, port planning and fisheries management. They link marine hazards to food security, shipping routes and coastal economies. The canonical description is on the STEM Commons.
Marine heatwave analysis
Sea surface and subsurface temperatures are compared with seasonal climatologies to identify marine heatwaves, their depth and their persistence.
Wave climate assessment
Wave hindcasts and buoy records describe typical and extreme wave conditions for coastal design and port operations.
03Geography
Ocean state in Pacific Island states.
Marine heat, sea temperature and chlorophyll over Pacific Island states, from NASA GIBS. Each layer carries its own date.
The interactive map needs JavaScript; the layer list and sources are below.
Layers 3
Ocean state, for this page
About this layer
- Evidence
- Observed
- Source
- GHRSST MUR25 (NASA JPL PO.DAAC)
- Provider
- NASA JPL PO.DAAC
- Licence
- NASA open data
- Vintage
- daily; Satellite analysis
- Newest at build
- 2026-10-12
- Resolution
- about 2 km grid
- Uncertainty
- Satellite analysis of how far sea temperature departs from its usual value for the date shown; a marine heat indicator, not a coral bleaching alert.
- Reached through
- gibs.earthdata.nasa.gov, only after you allow the live map
About this layer
- Evidence
- Observed
- Source
- GHRSST MUR (NASA JPL PO.DAAC)
- Provider
- NASA JPL PO.DAAC
- Licence
- NASA open data
- Vintage
- daily; Satellite analysis
- Newest at build
- 2026-10-12
- Resolution
- about 1 km grid
- Uncertainty
- Gap-filled satellite analysis of sea surface temperature for the date shown; not a reef or species condition report.
- Reached through
- gibs.earthdata.nasa.gov, only after you allow the live map
About this layer
- Evidence
- Observed (clouds and sun glint leave gaps)
- Source
- MODIS Aqua ocean colour (NASA OB.DAAC)
- Provider
- NASA OB.DAAC
- Licence
- NASA open data
- Vintage
- daily; Satellite retrieval; clouds and sun glint leave gaps
- Newest at build
- 2026-10-13
- Resolution
- about 1 km grid
- Uncertainty
- Satellite estimate of chlorophyll-a near the sea surface on the day shown, an indicator of plankton and ocean productivity; not a measure of fish stocks or harmful blooms.
- Reached through
- gibs.earthdata.nasa.gov, only after you allow the live map
About this layer
- Evidence
- Observed
- Source
- VIIRS NOAA-20 corrected reflectance (NASA LANCE)
- Provider
- NASA LANCE
- Licence
- NASA open data
- Vintage
- daily; Satellite image
- Newest at build
- 2026-10-14
- Resolution
- about 250 m grid
- Uncertainty
- Satellite image. Satellite or model raster as the provider publishes it. Clouds, swath gaps and retrieval error leave gaps and noise; values are indicators, not measurements at a place.
- Reached through
- gibs.earthdata.nasa.gov, only after you allow the live map
About this layer
- Evidence
- Modelled (latest year GIBS publishes)
- Source
- MODIS Terra and Aqua land cover (MCD12Q1) (NASA LP DAAC)
- Provider
- NASA LP DAAC
- Licence
- NASA open data
- Vintage
- yearly; Satellite classification; latest year GIBS publishes
- Newest at build
- 2024-01-01
- Resolution
- about 500 m grid
- Uncertainty
- Satellite land cover classes for the year shown, including croplands; a classification with known errors, not a farm register.
- Reached through
- gibs.earthdata.nasa.gov, only after you allow the live map
About this layer
- Evidence
- Observed (persistent cloud still leaves gaps)
- Source
- VIIRS NOAA-20 Level 3, 8-day (NASA LANCE)
- Provider
- NASA LANCE
- Licence
- NASA open data
- Vintage
- 8-day; Satellite 8-day composite; persistent cloud still leaves gaps
- Newest at build
- 2026-09-14
- Resolution
- about 1 km grid
- Uncertainty
- Satellite skin temperature of the ground over the 8 days ending on the date shown, a heat exposure indicator; not air temperature, heat index or a heat warning.
- Reached through
- gibs.earthdata.nasa.gov, only after you allow the live map
Keyboard, with the map focused
Hold Ctrl or ⌘ and scroll to zoom
Latest available
NASA GIBS / EOSDIS · ASTER GDEM (METI, NASA) · Blue Marble (NASA) · © OpenStreetMap contributors (ODbL) · Natural Earth
Loading the latest NASA imagery.
Drag to move. Ctrl or ⌘ and scroll, pinch or the buttons to zoom; hover for the values under the pointer; reset returns to the region.
Ocean state, framed on Pacific Island states.Satellite and model products as NASA publishes them, each with its own date. They are indicators, not assessments of any place.
Data: NASA GIBS · ASTER GDEM · Blue Marble · © OpenStreetMap contributors · Natural Earth · NASA EONET · NASA PACE OCI · NASA JPL OPERA DIST-ALERTSources and licences
- We acknowledge the use of imagery provided by services from NASA’s Global Imagery Browse Services (GIBS), part of NASA’s Earth Science Data and Information System (ESDIS). Colours redrawn from the published colour map; values averaged into hexagonal cells where shown (modified). NASA open data
- We acknowledge the use of imagery provided by services from NASA’s Global Imagery Browse Services (GIBS), part of NASA’s Earth Science Data and Information System (ESDIS). Colours redrawn from the published colour map; values averaged into hexagonal cells where shown (modified). NASA open data
- GHRSST Level 4 MUR analyses, NASA Jet Propulsion Laboratory; distributed by the NASA Physical Oceanography DAAC (PO.DAAC); imagery via NASA GIBS. Colours redrawn from the published colour map; values averaged into hexagonal cells where shown (modified). NASA open data
- MODIS Aqua ocean colour, NASA Ocean Biology Processing Group; distributed by the NASA Ocean Biology DAAC (OB.DAAC); imagery via NASA GIBS. Colours redrawn from the published colour map; values averaged into hexagonal cells where shown (modified). NASA open data
- VIIRS near-real-time products (flood, land surface temperature, snow cover, corrected reflectance), NASA LANCE; imagery via NASA GIBS. Colours redrawn from the published colour map; values averaged into hexagonal cells where shown (modified). NASA open data
- MODIS land products (vegetation indices, gross primary production, land cover), NASA LP DAAC and LANCE; imagery via NASA GIBS. Colours redrawn from the published colour map; values averaged into hexagonal cells where shown (modified). NASA open data
- ASTER GDEM is a product of METI and NASA (ASTER Global Digital Elevation Model V003, NASA LP DAAC); imagery via NASA GIBS. Colours redrawn from the published colour map; values averaged into hexagonal cells where shown (modified). Cite as: NASA/METI/AIST/Japan Spacesystems and U.S./Japan ASTER Science Team (2019). ASTER Global Digital Elevation Model V003. doi:10.5067/ASTER/ASTGTM.003. NASA open data
- Made with Natural Earth. Free vector and raster map data @ naturalearthdata.com. Public domain
- © OpenStreetMap contributors (ODbL), via NASA GIBS (coastlines, boundaries, roads and place names). Colours redrawn from the published colour map; values averaged into hexagonal cells where shown (modified). ODbL
- Blue Marble, NASA Earth Observatory; imagery via NASA GIBS. Colours redrawn from the published colour map; values averaged into hexagonal cells where shown (modified). NASA open data
- Context on the globe and flat map: coastlines, boundaries, roads and place names from NASA GIBS reference layers (OpenStreetMap data, ODbL, © OpenStreetMap contributors); Blue Marble imagery as an optional base; 3D terrain and the elevation read-out from the ASTER GDEM elevation colour index (5 m to 200 m classes, exaggerated for legibility). Boundaries are drawn as published and imply no position on any territory.
- Live events: NASA Earth Observatory Natural Event Tracker (EONET); events are indicative and keep their original source links.
- Live: NASA EONET Events are indicative, not authority warnings.
- Observed (EO): NASA PACE OCI. We acknowledge the use of imagery provided by services from NASA’s Global Imagery Browse Services (GIBS), part of NASA’s Earth Science Data and Information System (ESDIS).
- Observed (EO): NASA JPL OPERA DIST-ALERT (contains modified Copernicus Sentinel data 2026). We acknowledge the use of imagery provided by services from NASA’s Global Imagery Browse Services (GIBS), part of NASA’s Earth Science Data and Information System (ESDIS).
- NASA GIBS: We acknowledge the use of imagery provided by services from NASA’s Global Imagery Browse Services (GIBS), part of NASA’s Earth Science Data and Information System (ESDIS).
- Weather data by Open-Meteo.com (https://open-meteo.com/), licensed under CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/).
- Optional layers (10 sources in the layer list: live, forecast, observed and context) print their provider credit on the map and here when switched on; forecasts are model output and derived indices are estimates.
Layers and dates
- Sea surface temperature anomaly: GHRSST MUR25, NASA JPL PO.DAAC · 12 Oct 2026
- Sea surface temperature: GHRSST MUR, NASA JPL PO.DAAC · 12 Oct 2026
- Ocean chlorophyll-a concentration: MODIS Aqua ocean colour, NASA OB.DAAC · 12 Oct 2026
- True colour: VIIRS NOAA-20 corrected reflectance, NASA LANCE · 13 Oct 2026
- Land cover type (IGBP), yearly: MODIS Terra and Aqua land cover (MCD12Q1), NASA LP DAAC · 2024
- Land surface temperature, day, 8-day composite: VIIRS NOAA-20 Level 3, 8-day, NASA LANCE · 14 Sep 2026
04Data
What the method consumes.
Datasets and records used by ocean and coastal science on this platform, with the role each plays and the label its values carry. Sources are listed in the source register.
| Data | Role | Label |
|---|---|---|
| Argo floats | Subsurface temperature and salinity | OBSERVED |
| Satellite altimetry | Sea surface height | OBSERVED |
| Copernicus Marine reanalyses | Consistent ocean fields | MODELLED |
| Wave buoys | Wave conditions | OBSERVED |
05Monitor
Forecast verification.
The screen a team would use to follow this method: its measures, states and decisions. Names are examples and values are illustrative.
Forecast verification
Oceans and coasts · Ocean science for coastal risk · Run R-9349
Skill above referenceGCRI · Oceans and Coasts
Forecast with range
Method card
- Method
- Ocean and coastal science
- Reference
- climatology
- Lead times
- 1 to 12 steps
- Label
- MODELLED
Verification by lead time
held-out period
| T+2 | 0.15 | 0.29 | 0.23 | Skilful |
| T+4 | 0.16 | 0.26 | 0.09 | Skilful |
| T+6 | 0.44 | 0.10 | 0.15 | Skilful |
| T+8 | 0.17 | 0.26 | 0.23 | Skilful |
06Validation
How results are checked.
Models are checked against tide gauge records, altimetry and in situ profiles. Hindcasts of past storms and heatwaves test predictive skill.
| Check | How it is done |
|---|---|
| Budget closure | The sum of sea-level components is compared with observed change |
| Climatology consistency | Heatwave definitions state the baseline and threshold used |
| Model-buoy comparison | Wave hindcasts are validated against buoy records |
Coastal processes at fine scale and ice sheet contributions to sea level remain uncertain. Observations of the deep ocean and polar seas are sparse.
07Twin and cascade simulator
Model ocean science for coastal risk as a system. Run the cascade.
Assembled from the Nexus Standards area profile Oceans and coasts risk standards: the hazards it names, the systems and sectors that carry the loss, the controls that dampen it and the data that observe it. Choose the components, pick an initiating hazard and step through the cascade. The Map view places the run on an example geography with open data. Every coupling weight is a stated assumption you can change. A teaching model, not a forecast, an assessment or a certification. To model a place of your own choosing, open the full System Builder.
Hazards
- Sea-level rise
- Storm surge
- Coastal erosion
- Heatwave
- Ocean acidification
- Harmful algal bloom
- Extreme fire weather (set off downstream)
- Wildfire (set off downstream)
- Heat-driven grid stress (set off downstream)
- Agricultural drought (set off downstream)
- Flash drought (set off downstream)
- Snow drought (set off downstream)
- Ground-level ozone episode (set off downstream)
- Meteorological drought (set off downstream)
- River flood (set off downstream)
- Coastal flood (set off downstream)
- Estuary flood (set off downstream)
- Mass displacement (set off downstream)
Systems and couplings
- Oceans and coasts risk standards
- Supply chain and trade risk Cascade
- Food and agriculture risk standards Cascade
- Climate risk standards Common driver and feedback
- Cities and urban systems risk standards Exposure
Controls
NS-0Constitution and principlesNS-1The UNI and the artefact catalogue (grammar v0.2: domain, sector, region and environment segments)NS-3Risk record UNIs (grammar, legacy crosswalk, allocation authority)NS-3bDataset and product metadata profile (STAC, DCAT, PROV-O)NS-5Figure, map and visualisation standard (with the UI/UX kit)NS-9Contextual UNIs (deployments, instances, programme instances)NS-11Verification and monitoring (evidence, attestations, zero-trust conformance observation)NRS-X3Oceans and coasts riskNRS-H11Hazard family: Coastal and sea-level hazards (NHS-1 water.coastal)NRS-H79Hazard family: Mental health crises (NHS-1 health.mental)NRS-H12Hazard family: Ocean-state extremes (NHS-1 water.ocean-state)NRS-H67Hazard family: Ocean circulation and marine tipping (NHS-1 planet.ocean-tipping)NRS-K18Domain pack profile: Oceans coastal (DOMAIN-018)
Observation
- Copernicus Marine Service ocean products (listed for reference)
- Coral Reef Watch daily 5 km heat stress products (listed for reference)
- PSMSL tide gauge mean sea level records (listed for reference)
- GEBCO global bathymetric grid (listed for reference)
- Argo float profiles (listed for reference)
- Average marine acidity (pH) measured at agreed suite of representative sampling stations
- Index of coastal eutrophication and floating plastic debris density
- Direct economic loss attributed to disasters in relation to GDP, including damage to critical infrastructure
Example geography
- Pacific Island states: 150 hexagonal cells
- Night lights tonight, outages (VIIRS Day/Night Band), NASA GIBS
- Surface water through cloud, 30 m (OPERA DSWx-S1 radar), NASA GIBS
- Rain rate, last half hour (IMERG), NASA GIBS
- Surface air temperature, daytime (AIRS), NASA GIBS
08Connections
Topics that rely on this method.
09Risk and response
Coupled risk, applied response.
The sectors coastal storm surge touches and how strongly they depend on each other: what a study has to observe and model together.
Choose a context
ACoupled risk across six sectors10 / 15 relations
Sectors · Coastal storm surgeStress
applied to
BApplied response across six pillars12 / 18 handoffs
Pillars · Coastal storm surgeKPI
In this contextDependence or handoff, heavier is strongerOutside this context
Programme yearAll phases
Context
Coastal storm surge
Mangroves and dunes absorb the surge; where they are gone, ports, substations and water intakes take it.
W · E · I · F · H · B
Risk
- Sectors
- 5 of 6
- Relations
- 10 of 15
- Coupling
- 0.64 share of total
Hover a corner, a line or a row to trace it across both sides.
Route
Applied to coastal storm surge
L · F · U · S · R · A
Response
- Pillars
- 5 of 6
- Handoffs
- 12 of 18
- Loops
- 8 closed
Expected value
- What is at stake
- $390Ba year at least, in infrastructure disruption costs to households and firms in low- and middle-income countriesWorld Bank, Lifelines, 2019
- Return on resilience
- 4 : 1benefit to costWorld Bank, Lifelines, 2019
- Avoided loss
- $80Bflood losses avoided a yearGlobal Commission on Adaptation, Adapt Now, 2019
Hover a pillar, a line or a row to read how it is applied.
A: a teaching cascade (shock 0.6, gain 0.35, four rounds) over teaching values for a typical city-region, not measurements. B: illustrative applications and the KPI each pillar answers for; values are published benchmarks, cited, not forecasts. Open events: NASA EONET, live.
10Stewardship
Who maintains the method.
Oceans and Coasts stewards ocean and coastal science for the Consortium and reviews how it is applied across platforms.
11Methods and evidence
How ocean science for coastal risk is modelled, measured and tested.
The model, its assumptions, its data and its uncertainty, in the form a scientist or engineer would check. Structures follow published methods. The values drawn are illustrative, not findings.
Earth observation chain
How a satellite or sensor record becomes evidence on ocean science for coastal risk, and where each step adds uncertainty.
- 01 · Acquireorbit, sensor and revisitUncertainty: gaps from cloud and orbit
- 02 · Calibrateradiometric and geometricUncertainty: sensor drift
- 03 · Correctatmosphere and terrainUncertainty: aerosol and slope assumptions
- 04 · Retrieve or classifythe variable or the classUncertainty: model and training error
- 05 · Validateagainst ground truthUncertainty: sample design and size
- 06 · Publishwith error bars and lineageUncertainty: stated, never hidden
FAIR guiding principles · GO FAIR and FORCE11W3C PROV · World Wide Web ConsortiumGuidance on consistent treatment of uncertainties · IPCCCEOS Analysis Ready Data · Committee on Earth Observation Satellites
12Questions
Questions and answers.
What are the limits of ocean and coastal science in this field?
Coastal processes at fine scale and ice sheet contributions to sea level remain uncertain. Observations of the deep ocean and polar seas are sparse.
How are results checked?
Models are checked against tide gauge records, altimetry and in situ profiles. Hindcasts of past storms and heatwaves test predictive skill.
Are the values on this page real?
The data names, roles and checks are real descriptions of practice. The canvas shows a design of the method’s use, not a run; no result is reported here.
Where else is this method applied?
The canonical method page lists every platform that applies it.
13Process
How the process runs.
Process
Ocean science for coastal risk: Flood forecasting and warning chain
The WMO flood forecasting manual and Early Warnings for All describe the chain from forecast to action, across EW4All’s four pillars.
01 Forecast
- 01Rainfall forecastSourceNumerical weather prediction and nowcasts supply rainfall input. Ensembles can apply to weather prediction and hydrological models.
- 02Hydrological modelModel · Island councilA hydrological model turns rainfall into runoff and discharge. The manual covers model choice, parameters and calibration.
- 03Hydraulic modelModelA hydraulic model routes the discharge to water levels along the river and floodplain. The place is set by the page.
- 04Inundation mapsDatasetInundation forecasting combines a level-and-flow model with a digital flood plain surface, the manual’s most sophisticated public service.
02 Warning
- 05ThresholdsGateForecasts are compared with thresholds agreed in advance, as in a threshold-based alert service. Impact-based guidance was not read.
- 06Warning decisionDecision · Island councilThe agency responsible for forecasts and warnings decides on the warning. It should understand the roles of the other agencies concerned.
- 07Warning disseminationStepWarnings are communicated through the channels people use. This is EW4All pillar 3, warning dissemination and communication.
03 Response
- 08Early actionStepPeople and institutions act on the warning. This is EW4All pillar 4, preparedness and response capabilities.
- 09Forecast verificationStepForecasts are verified using hits, misses and false alarms. The manual lists probability of detection, false alarm rate and threat score.
Neutral outline of a published external standard or method, from its issuing body. Not a record of operation. Nexus does not perform, certify or approve any step shown. A gate or decision belongs to the party the source names.
ReportsContribute
Contribute evidence from this page.
Reports is the Consortium’s quarterly publication. What you know about this subject can become evidence, a case or a correction in the next edition, credited to you and published under CC BY 4.0 where it is your own work.
GCRIOceans and CoastsGlobal Sector Risk and ResilienceObservatory Signal
- EmailGateway GW-GCRISend it from this pageEvidence, a correction, a case, a method, a review, a translation or profile input. It arrives tagged with this page, so the editor who owns it receives it.
- ZenodoOpen depositDeposit it and submit to the communityPublish your own record on Zenodo with your ORCID iD, then submit it to the Reports community there. Curators review it; the DOI stays yours.
- ReportsGCRISee every way to contributeThe contribution types, how each is reviewed, what credit you receive, the licence and what is never accepted.
Never send personal data, sensitive infrastructure detail or anything you have no right to share. A contribution is reviewed before use; sending it confers no authorship or editorial rights, and sponsorship never buys a finding.
Oceans and Coasts
Bring a method, a dataset or a question.
Information and enquiries are open today. An enquiry receives a reference and names the next step; applications, payments, compute allocations and registrations open only when their team, terms and review capacity exist.
Legal
Legal documents.
Maps, data and figures on this site are shown for context and general information. They are not advice, forecasts or warnings; the limits of the information are set out in the Disclaimers and Data Notices.