These data are atmospheric forcings from NOAA's Analysis of Record for Calibration (AORC 2024) summarized over the CAMELS catchments (Addor et al. 2017), however, the delineations over those CAMELS basins were updated by Andy Wood (2024) using the basin boundaries produced for the USGS GagesII effort (Falcone 2011).

Data collected using this repository code: https://github.com/jmframe/CIROH_DL_NextGen/tree/main/forcing_prep, which should be somewhat derivative of this: https://github.com/CIROH-UA/ngen-datastream/tree/main/forcingprocessor.

There are eight variables representing the meteorological conditions: Total Precipitaion (APCP_surface) - Hourly total precipitation (kgm-2 or mm) for Calibration (AORC) dataset Air Temperature (TMP_2maboveground) - Temperature (at 2 m above-ground-level (AGL)) (K) Specific Humidity (SPFH_2maboveground) - Specific humidity (at 2 m AGL) (g g-1) Downward Long-Wave Radiation Flux (DLWRF_surface) - longwave (infrared) radiation flux (at the surface) (W m-2) Downward Short-Wave Radiation Flux (DSWRF_surface) - Downward shortwave (solar) radiation flux (at the surface) (W m-2) Pressure (PRES_surface) - Air pressure (at the surface) (Pa) U-Component of Wind (UGRD_10maboveground) - (west-east) - components of the wind (at 10 m AGL) (m s-1) V-Component of Wind (VGRD_10maboveground) - (south-north) - components of the wind (at 10 m AGL) (m s-1)

The data include a timestamp from Coordinated Universal Time (UTC; AORC 2021).

References: Addor, N., Newman, A. J., Mizukami, N., and Clark, M. P.: The CAMELS data set: catchment attributes and meteorology for large-sample studies, Hydrol. Earth Syst. Sci., 21, 5293–5313, https://doi.org/10.5194/hess-21-5293-2017, 2017. AORC. 2021. Analysis of Record for Calibration Version 1.1 - Sources, Methods, and Verification, National Oceanic and Atmospheric Administration (NOAA), National Weather Service (NWS), Office of Water Prediction (OWP), Silver Spring, MD.https://www.weather.gov/media/owp/operations/aorc_v1_1_methods.pd AORC. 2024. NOAA Analysis of Record for Calibration (AORC) Dataset was accessed July 2024 from https://registry.opendata.aws/noaa-nws-aorc. Falcone, J., 2011, GAGES-II: Geospatial Attributes of Gages for Evaluating Streamflow: U.S. Geological Survey data release, https://doi.org/10.5066/P96CPHOT. https://www.sciencebase.gov/catalog/item/631405bbd34e36012efa304a Wood. 2024. CAMELS basins delineation.

Clear Creek at Golden, Colorado (USGS 06719505) is a small, high-elevation, snow-dominated headwater basin on Colorado's Front Range that has been used as a pilot basin for modeling studies at the Colorado School of Mines (see: https://github.com/mines-ciroh/clear_creek_demo). In addition to its proximity to the Mines campus, Clear Creek at Golden, CO is also one of approximately 200 study basins in NOAA Office of Water Prediction's (OWP) Hydrologic Ensemble Forecast System (HEFS) testbed. This resource contains key model inputs to run NOAA's Next Generation Water Resources Modeling Framework (Nextgen) across Clear Creek. These data include 1) a geopackage containing the Clear Creek Nextgen v2.2 hydrofabric, with layers that describe the catchments, flowpaths, attributes, and more; and 2) the 1979-2024 retrospective AORC v1.1 forcings mapped to the Clear Creek v2.2 hydrofabric catchments in Nextgen-compliant netCDF format.

Acknowledgements: - This dataset was supported by a project grant to the Colorado School of Mines (CSM) from the NOAA Cooperative Institute for Research to Operations in Hydrology (CIROH). CIROH is funded via the NOAA Cooperative Agreement with The University of Alabama (NA22NWS4320003). - The hydrofabric data on this resource were subset from v2.2 of the Lynker Spatial hydrofabric (s3://lynker-spatial/hydrofabric/v2.2/)

Resources: https://github.com/mines-ciroh/clear_creek_demo https://www.lynker-spatial.com/data/hydrofabric/v2.2/conus/ https://registry.opendata.aws/noaa-nws-aorc/ https://water.noaa.gov/gauges/06719505 https://waterdata.usgs.gov/monitoring-location/06719505

The DayflowV2 dataset provides multiple meteorologic forcings driven daily and monthly scale streamflow information at about 2.7 million NHDPlusV2 stream reaches in the conterminous US (CONUS). DaymetV4, Stage-IV, and Analysis of Period of Record for Calibration (AORC) forcings and their corresponding hybrids drive a nationally scalable modeling framework integrating the simulated runoff from the Variable Infiltration Capacity (VIC) model with the Routing Application for Parallel computatIon of Discharge (RAPID) routing model. Streamflow with (Assimilated) and without (Naturalized) streamflow assimilation at US Geological Survey (USGS) streamflow monitoring sites are included in DayflowV2. A comprehensive evaluation of streamflow at 7,526 USGS gauges is performed for both streamflow types. The resulting key evaluation metrics are also included in the Dayflow Dataset. The reanalysis data are available for variable periods; 36 years (1980 – 2015) for DaymetV4 (DayflowV1), 18 years (2002 – 2019) for Stage-IV and its hybrids, and 40 years (1980-2019) for AORC and its hybrids.