Dataset: North American marine species distribution projections

SUMMARY OF METHODS
Projections for shifts in thermal habitat for marine species on the North American continental shelf during the 21st century were conducted by coupling models of species thermal habitat with climate projection model output. Habitat models for each species were based on extensive trawl survey data from the continental shelf of the U.S. and Canada. Each haul from this survey dataset was paired with environmental data, including five ocean temperature variables and two seafloor characteristics. Generalized additive models(GAMs) were used to statistically describe each species’ thermal habitat preference. The habitat model of each species was applied to projections of future climate, to predict how the distribution of suitable habitat will shift during the 21 st century. Two future carbon emissions scenarios (RCP 2.6 and 8.5) were used, which represented a potential best and worst case outcome for future ocean warming. Within each future scenario, sixteen different general circulation models (GCMs) were used to project future ocean temperatures annually from 2007-2100 on the continental shelf. The spatial resolution of the GCMs were standardized to a resolution of 0.25 degrees latitude and longitude based on historical climatology data, by using statistical downscaling. The projection grid was further refined to ~6 km based on seafloor characteristics. A total of 32 possible future ocean climate outcomes were generated for projecting species habitat shifts. Annual projections of thermal habitat were calculated for each species by applying the habitat models to projections of climate from 2007 to 2100. Annual values were aggregated into 20 year mean values within each RCP and GCM.

GENERAL FILE DESCRIPTION
Each file contains 21st century projection data for a single species and one of two RCPs (representative concentration pathway). The files are stored as .RData files and each contains a single data frame to be used with R computing software. Each row of data consists of projected catch-per-unit-effort for 16 different general circulation models (mean1 through mean16) within a specific latitude-longitude referenced grid cell, for one of five time periods (2007-2020, 2021-2040, 2041-2060, 2061-2080, 2081-2100).

FILENAME CONVENTION (separated by _)
The beginning of each file contains the species scientific name.
The Atlantic (including the Gulf of Mexico) and Pacific Ocean species are identified by Atl or Pac, respectively rcp26 or rcp85 identifies the two carbon emission scenarios used.
jas indicates that these projections are for the months of July-August-September
prediction_AGG indicates that these are predictions aggregated into 20 year time periods.

COLUMNS IN DATA FRAMES
year-range - projections are mean annual values within five time periods
latitude and longitude - reference grid cell locations
mean1 through mean16 - the projected values of catch-per-unit-effort within each of 16 different general circulation models (i.e., each column represents one general circulation model). Mean values are calculated with the annual estimates within that year-range. The order of the general circulation models: bcc-csm1-1-m', 'bcc-csm1-1', 'CanESM2', 'CCSM4', 'CESM1-CAM5', 'CNRM-CM5', 'GFDL-CM3', 'GFDL-ESM2M', 'GFDL-ESM2G', 'GISS-E2-R', 'GISS-E2-H', 'IPSL-CM5A-LR', 'IPSL-CM5A-MR', 'MIROC-ESM', 'MPI-ESM-LR', 'NorESM1-ME.