What Is a Climate Data API?
A climate data API provides programmatic access to climate projections, historical climate records, and risk scores. Unlike weather APIs that deliver short-term forecasts and current conditions, climate data APIs focus on long-term trends: temperature trajectories under different emission pathways, flood return periods, drought severity projections, and physical risk ratings.
Organizations use climate data APIs to automate physical risk assessments, generate TCFD-aligned reports, screen real estate portfolios, and evaluate supply chain exposure. The data typically originates from global climate models (GCMs) like those in the CMIP6 ensemble, reanalysis datasets, and satellite-derived observations.
The right climate data API depends on your use case. Researchers working with raw model output need different capabilities than a risk analyst who needs a score for 500 locations by Friday. This guide breaks down the best free and paid climate data APIs available today, with the specific strengths and limitations of each.
How to Choose a Climate Data API
Not every climate data API serves the same purpose. Before evaluating providers, clarify what you need along these five dimensions:
- Data scope: How many hazards are covered? Does the API include scenario pathways like SSP2-4.5 and SSP5-8.5? Does it project out to 2050 or beyond?
- Spatial resolution: Global climate models run at 50-100km grid cells. Some APIs downscale to 1-10km. Point-level APIs resolve risk for a single coordinate. The difference matters when assessing a specific facility versus a country-level portfolio.
- Output format: Raw climate data ships as NetCDF or GRIB files, which require specialized libraries to process. REST APIs returning JSON are simpler to integrate into business applications.
- Ease of integration: Does the provider offer a REST endpoint, a Python SDK, or both? How complex is authentication? Can you batch requests?
- Pricing model: Free government APIs have generous limits but no SLAs. Commercial APIs charge per request or per report but guarantee uptime and support.
Best Free Climate Data APIs
NOAA Climate Data Online (CDO) API
The NOAA Climate Data Online API provides access to one of the largest archives of historical weather and climate records in the world. The dataset includes daily summaries, monthly normals, and station-level observations going back decades.
Coverage: Primarily U.S. stations, with limited global coverage through GHCN (Global Historical Climatology Network).
Access: Free. Requires a token (instant registration). Rate-limited to 5 requests per second and 10,000 per day.
Output: JSON via REST API.
Best for: Historical U.S. climate records, station-level temperature and precipitation trends, academic research. Not designed for forward-looking risk projections or scenario analysis.
Copernicus Climate Data Store (CDS) API
The Copernicus CDS API is the gold standard for free global climate data. Managed by the European Centre for Medium-Range Weather Forecasts (ECMWF), it hosts ERA5 reanalysis data, CMIP6 climate projections, seasonal forecasts, and satellite observations.
Coverage: Global, with datasets spanning 1940 to 2100 (projections).
Access: Free. Python-based client library (cdsapi). Requests are queued and processed asynchronously, so large downloads may take minutes to hours.
Output: NetCDF and GRIB formats. Requires Python and xarray or similar libraries to process.
Best for: Researchers and data scientists who need raw CMIP6 model output, ERA5 reanalysis grids, or satellite-derived climate indicators. Processing the raw data into usable risk metrics requires significant technical effort.
World Bank Climate Data API
The World Bank Climate Knowledge Portal provides pre-aggregated climate statistics at the country and river basin level. The API delivers historical averages and GCM-based projections for temperature, precipitation, and derived indicators.
Coverage: Global, aggregated by country or basin. No point-level data.
Access: Free. No authentication required. Simple REST endpoints.
Output: JSON. Clean, pre-processed aggregates ready for dashboards and reports.
Best for: Development organizations, country-level climate overviews, policy analysis. Too coarse for facility-level or portfolio-level risk assessment.
Open-Meteo Climate API
Open-Meteo offers a free climate data API built on regional downscaled models from the HighResMip working group. It provides temperature, precipitation, wind, and radiation projections at roughly 10km resolution.
Coverage: Global, 10km grid resolution.
Access: Free for non-commercial use. REST API with no authentication required.
Output: JSON. Straightforward request/response pattern.
Best for: Quick prototyping, non-commercial projects, developers building climate-aware applications who need projection data without the overhead of processing raw NetCDF files.
Best Paid Climate Data APIs
Continuuiti Climate Risk API
Continuuiti’s Climate Risk API takes a different approach from raw data providers. Instead of returning model output that you need to interpret, it returns risk ratings and composite scores for 12 physical hazards at any global coordinate. The API runs NASA NEX-GDDP-CMIP6 projections through hazard-specific risk models and returns structured, report-ready output.
For developers building integrations, see the full Climate Risk API documentation, which covers endpoints, authentication, code examples, and the response field reference.
Coverage: Global, point-level analysis for any latitude/longitude.
Hazards: 12 physical hazards including river flood, sea level rise, drought, heat wave, wildfire, landslide, and water stress.
Scenarios: SSP2-4.5 (moderate emissions) and SSP5-8.5 (high emissions) across baseline, 2030, 2040, and 2050 time horizons.
Output: JSON via REST API. Individual hazard ratings (Low to Extreme), composite risk scores with confidence levels, and risk trajectory data.
Best for: Physical risk assessment, TCFD/ISSB-aligned climate scenario analysis, real estate due diligence, portfolio screening. Built for teams that need actionable risk scores rather than raw climate grids.
Meteomatics Climate API
Meteomatics provides climate projection data through their weather API infrastructure. The climate data API uses the MRI-ESM2.0 global climate model, covering the period from 2015 to 2100 with parameters including temperature, precipitation, wind, and radiation.
Coverage: Global. Their proprietary downscaling models (EURO1k, US1k) deliver 1km resolution across Europe and the United States.
Output: REST API supporting JSON, CSV, and NetCDF formats.
Best for: Teams that need both weather forecasting and climate projection data from a single provider. Strongest coverage in Europe.
Correntics Climate Data API
Correntics focuses on physical risk assessment and climate extreme indices. Their API combines real-time weather data with climate projection indicators specifically designed for risk scoring applications.
Coverage: Global. Climate extreme indices plus natural hazard information.
Output: REST API with JSON response.
Best for: Insurance underwriting, real estate risk scoring, and organizations building climate risk into existing assessment workflows.
Tomorrow.io
Tomorrow.io combines operational weather intelligence with climate risk scoring. Their platform serves both near-term weather decisions and longer-horizon climate exposure analysis, making it a fit for operations-focused teams.
Coverage: Global. Weather data at 500m resolution; climate risk at coarser grids.
Output: REST API, JSON. Enterprise pricing with custom SLAs.
Best for: Supply chain and logistics operations that need both daily weather intelligence and annual climate risk assessments from one platform.
Climate Data API Comparison
The table below summarizes how each climate data API stacks up across the criteria that matter most: cost, coverage, resolution, and intended use case.
| API | Free Tier | Data Type | Resolution | Output | Best For |
|---|---|---|---|---|---|
| NOAA CDO | Yes (10K/day) | Historical records | Station-level | JSON | U.S. climate history |
| Copernicus CDS | Yes (queued) | Reanalysis + projections | 25-100km grid | NetCDF, GRIB | Research, raw CMIP6 |
| World Bank | Yes (no auth) | Aggregated projections | Country/basin | JSON | Policy, development |
| Open-Meteo | Yes (non-commercial) | Downscaled projections | 10km grid | JSON | Prototyping, MVPs |
| Continuuiti | No | Risk scores + projections | Point-level | JSON | TCFD, portfolio risk |
| Meteomatics | Trial available | Weather + climate | 1-100km | JSON, CSV, NetCDF | Combined weather/climate |
| Correntics | No | Extreme indices + hazards | Global grid | JSON | Insurance, risk scoring |
| Tomorrow.io | Limited free tier | Weather + climate risk | 500m (weather) | JSON | Supply chain, logistics |
How to Get Started with a Climate Data API
Most climate data APIs follow standard REST conventions. The typical integration pattern looks like this:
1. Register and authenticate. Free APIs (NOAA, Open-Meteo) require a token or no authentication at all. Commercial APIs issue API keys through a dashboard after account creation.
2. Structure your request. Climate data API requests generally include a location (coordinates or region identifier), a time range (historical period or projection year), and the variables you need (temperature, precipitation, risk scores). Here is a simplified example in Python:
import requests
# Example: querying a climate data API
response = requests.get(
"https://api.example.com/v1/climate",
params={
"lat": 40.7128,
"lon": -74.0060,
"scenario": "ssp245",
"horizon": "2050",
"variables": "temperature,precipitation"
},
headers={"Authorization": "Bearer YOUR_API_KEY"}
)
data = response.json()3. Parse the response. JSON responses from REST APIs can be processed directly in any language. NetCDF files from Copernicus or Meteomatics require Python libraries like xarray or netCDF4.
4. Handle rate limits. Free APIs enforce strict limits (NOAA: 5 requests/second). Batch your requests and cache results to stay within quotas. Commercial APIs offer higher throughput but monitor your usage against your plan.
Frequently Asked Questions
Is there a free climate data API?
Yes. NOAA’s Climate Data Online API, the Copernicus Climate Data Store API, the World Bank Climate Data API, and Open-Meteo all offer free access to climate data. NOAA and Copernicus provide the most comprehensive datasets. Free APIs are best suited for research, prototyping, and non-commercial applications. Commercial APIs add pre-processed risk scores, SLAs, and support.
What is the difference between a weather API and a climate data API?
Weather APIs deliver short-term data: current conditions, hourly forecasts, and 7-15 day predictions. Climate data APIs provide long-term projections spanning decades, historical climate records, and scenario-based analysis under different emission pathways (like SSP2-4.5 or SSP5-8.5). Weather APIs answer “will it rain tomorrow?” while climate data APIs answer “how will flood risk change at this location by 2050?”
How do I access NOAA climate data through an API?
Register for a free token at NOAA’s Climate Data Online portal. The API uses standard REST endpoints with JSON responses. Include your token in the request header. The API provides access to datasets including daily summaries (GHCND), monthly normals, and station observations. Rate limits are 5 requests per second and 10,000 per day.
Which climate data API is best for TCFD reporting?
For TCFD-aligned climate risk disclosure, you need an API that provides scenario-based physical risk analysis across multiple hazards and time horizons. Raw data APIs like Copernicus CDS can feed TCFD reports, but require significant processing to translate model output into the risk metrics that TCFD frameworks expect. Commercial APIs designed for risk assessment deliver report-ready output that maps directly to TCFD disclosure requirements.
Can I get climate projections through an API?
Yes. Several APIs serve climate projection data. Copernicus CDS provides raw CMIP6 model output as NetCDF files. Open-Meteo serves downscaled projections at 10km resolution via a simple JSON API. Continuuiti and Correntics translate projections into risk scores and hazard ratings. The format depends on the provider: research-oriented APIs deliver raw gridded data, while commercial APIs return processed risk indicators.
Choosing the Right Climate Data API
The best climate data API for your project depends on where you sit on the build-versus-buy spectrum. If your team has climate scientists who can process NetCDF output, Copernicus CDS gives you the deepest free dataset available. If you need actionable risk scores at the location level without building a data pipeline, a commercial climate data API will get you there faster.
Start by defining your output requirements: raw model grids, aggregated statistics, or risk ratings. Match that to the provider whose data type and resolution fits. For most commercial applications requiring TCFD compliance or portfolio-level physical risk screening, purpose-built risk APIs offer the most direct path from API call to decision.
