caladaptaer

R access to Cal-Adapt climate projections

The caladaptaer package provides native R access to Cal-Adapt climate data from California’s Fifth Climate Change Assessment. The data are downscaled CMIP6 climate projections hosted on the Cal-Adapt Analytics Engine (CAE). Given a variable, model, scenario, and time window, caladaptaer reads the requested subset and returns either a stars grid or a data.frame.

What it does

• Discovers available models, scenarios, variables, and resolutions from the CAE catalog.
• Reads WRF and LOCA2 climate projections into R.
• Extracts time series for one or many locations.
• Builds CF-1.8 NetCDF meteorological driver files from hourly WRF data.

caladaptaer is a data access package. It does not model, bias-correct, or analyze climate data. The objects it returns work directly with the standard R geospatial and modeling stack.

Available data

The package reads the two main downscaling products hosted by CAE. See Data Access for product-selection guidance, time domains, and citations.

Dataset	Resolution	Step	GCMs	Scenarios	Period
WRF CMIP6 (WUS-D3)	45 / 9 / 3 km	Hourly	8	SSP3-7.0 (all); SSP2-4.5 and SSP5-8.5 (CESM2)	1980–2100
LOCA2-Hybrid	3 km	Daily	15	SSP2-4.5, SSP3-7.0, SSP5-8.5	1950–2100

Related Tools

Tool	Use Case	How it differs from caladaptaer
climakitae	Python access and analysis workflows for CAE data	Official Python toolkit for the Fifth Assessment data; caladaptaer supports native R access.
climakitaegui	Interactive Python menus for retrieving CAE data	Adds a GUI-style layer on top of climakitae; caladaptaer supports scriptable R workflows.
CAE intake catalog	Direct Python/xarray/dask access to the CAE Zarr catalog	Lower-level Python access to the same cloud-hosted data; caladaptaer wraps discovery and fetch operations for R users.
Cal-Adapt web tools	Browser-based exploration, maps, charts, and downloads	Useful for visual exploration; caladaptaer is for reproducible R scripts and model workflows.
caladaptR	R access to the legacy Cal-Adapt.org API	Targets the older Cal-Adapt API and Fourth Assessment-era datasets rather than the CAE cloud Zarr stores.

Guides and reference

Page	What is on it
Getting Started	Minimal installation and point time-series workflow
Data Access	Dataset background, product comparison, discovery, and fetch functions
Met Drivers	WRF to CF NetCDF meteorological drivers
Reference	Function documentation

Citing and license

caladaptaer is released under BSD-3-Clause. Please cite as

B V, A., & LeBauer, D. (2026). caladaptaer: Access Cal-Adapt Climate Data from R (Version 0.2.0) [Computer software]. https://github.com/lebauerapproach/caladaptaer