Data Releases

This dataset contains the growth index from annual growth bands in the shells of two bivalve clam species (Astarte borealis and Liocyma fluctuosa) captured in the Chukchi Sea, Alaska. The growth index is based on a measurement of the annual growth increment width that has been detrended for age-related differences in growth.

This data release documents seven tables that contain environmental tracer data and lumped parameter model (LPM) results that are used for assessing the distribution of groundwater age in 21 Principal Aquifers of the continental United States. Groundwater samples were collected from 1,279 sites and analyzed for environmental tracers: tritium, tritiogenic helium-3, sulfur hexafluoride, carbon-14, a

This data release provides a recursive-estimation framework to infer groundwater/surface-water exchange based on temperature time series collected at different vertical depths below the sediment/water interface. A heat-transport problem was formulated as a state-space model (SSM), in which the spatial derivatives in the convection/conduction equation are approximated using finite differences. The

The U.S. Geological Survey (USGS) works closely with the Mississippi Department of Transportation (MDOT) to provide information to be used by the MDOT for design of highway-drainage structures. MDOT spends millions of dollars annually for highway construction. Streamflow records, hydrologic analyses of basins, and hydraulic analyses of flooding potential at proposed highway crossings help the MDOT

Twenty quadrats within the burn perimeter of a September 2021 wildfire outside of Boise, Idaho were surveyed for the abundance of fire effects, biocrusts and vascular plants immediately post-fire. The fire was too small to be named. Char was measured as a proxy for fire intensity. Biocrusts were surveyed by morphogroup (crustose lichens, cup lichens, fruticose lichens, gelatinous lichens, short mo

This USGS data release contains landscape variables representing anthropogenic disturbances to stream habitats and natural variables summarized within local and network stream catchments of the National Hydrography Dataset Plus Version 2.1 (NHDPlusV2.1) as well as a 90 meter local and network buffer of stream reaches throughout the conterminous U.S. The source datasets compiled and attributed to

This USGS data release contains products that resulted from aquatic species distribution modeling in the United States on the National Hydrography Dataset Plus Version 2.1. Source data, supporting code and model results are documented in this data release. The file species_model_list.csv provides a list of most recent models for each combination of species, habitat, and region.

This USGS data release documents coarse ranges for 123 fish species in the conterminous United States for level 8 hydrologic units from the Watershed Boundary Dataset (WBD). These range maps were derived by combining known fish occurrence information from four data sources: point occurrences from the Aquatic Gap Analysis Project (AGAP) fish database, point occurrences from the IchthyMaps dataset,

This USGS data release includes a comma separated value (CSV) file that contains 19 reach-based dam metrics representing stream fragmentation and flow alteration for nearly 2.3 million stream reaches in the conterminous United States. Dam metrics fall into three main categories: count and density, distance-based, and cumulative reservoir storage (described below). These data were developed using

This USGS data release documents species distribution models for 271 fluvial fish species in their native ranges of the conterminous United States. Source data, supporting code and model results are documented in this data package. Boosted Regression Tree (BRT) models were used to develop presence/absence predictions for each of the National Hydrography Dataset Plus Version 2.1 stream segments w

This USGS data release documents presence and absences of 271 fish species in the conterminous United States for 35,918 stream reaches of the National Hydrography Dataset Plus Version2.1 (NHDPlusV2.1). Sample dates for this dataset span 1990-2019. Fish samples were aligned to the Integrated Taxonomic Information System (ITIS), where each species record was assigned a Taxonomic Serial Number (TSN).

Pollen was measured in ambient air by several methods and in wet atmospheric deposition samples at three monitoring sites in the National Atmospheric Deposition Program (NADP) National Trends Network. A method for counting pollen on filters was developed and provided pollen counts for NADP atmospheric wet-deposition samples and high-volume ambient air samplers (HVAS) for comparison with co-located