cpa_pre2021: Historical cold pool area calculations (cpa_pre2021)

In afsc-gap-products/coldpool: AFSC/RACE Groundfish Assessment Program EBS and NBS temperature products

Historical cold pool area calculations (cpa_pre2021)

Description

Historical temperature cold pool area (AREA_SUM_KM2_LTE2) and other temperature isotherm (AREA_KM2_MINUS1, AREA_KM2_0, AREA_KM2_1, AREA_KM2_2, AREA_KM2_LTE0, AREA_KM2_LTE1) areas that were calculated prior to 2021 by Bob Lauth, Lyle Britt, Dan Nichol, and Rebecca Haehn. These calculations were obtained from raster surfaces generated using ArcMap by interpolating temperatures using inverse distance weighting with a maximum of four nearest neighbor points for interpolation (search radius nmax = 4) and weighting function power equal to 2 (i.e., idp = 2). Default ArcGIS settings were used to generate rasters cells for interpolation (cell dimensions equal to the smaller horizontal or vertical dimension divided by 250). Protocols for including stations for interpolation varied among years but it was intended for all standard survey grid stations from the EBS survey to be included. In some years, it is possible that near-shore stations or red king crab resample stations were included in the calculations. Rasters were converted to polygon shapefiles and areas were calculated from polygons. The CRS used in ArcGIS .mxd files was North American Datum 1983 / Albers Equal Area Alaska (EPSG:3338). Historical weighted average temperature data products (AVGBSBT_PLUSNW, AVGBSST_PLUSNW, AVGBSBT_STANDARD, AVGBSST_STANDARD, AVGBSBT_NBS, AVGBSST_NBS, AVGBSBT_LT100M, AVGBSST_LT100M) were calculated by weighting temperature observations from survey stations in proportion to the area of the stratum where they were collected relative to the total survey area. Historical mean temperature for stations at bottom depths < 100 m (AVGBSBT_LT100M, AVGBSST_LT100M) were calculated by averaging temperature observations from samples collected at bottom depths < 100 m.

Usage

cpa_pre2021

Format

A data frame with 39 rows and 16 columns:

YEAR

Year

AREA_KM2_MINUS1

Area with bottom temperatures less than -1 celsius, in square kilometers

AREA_KM2_0

Area with bottom temperatures between -1 and 0 celsius, in square kilometers

AREA_KM2_1

Area with bottom temperatures between 0 and 1 celsius, in square kilometers

AREA_KM2_2

Area with bottom temperatures between 1 and 2 celsius, in square kilometers

AREA_SUM_KM2_LTE2

Cold Pool Index. Total area with bottom temperatures less than or equal to 2 celsius, in square kilometers

AREA_KM2_LTE1

Total area with bottom temperatures less than or equal to 1 celsius, in square kilometers

AREA_KM2_LTE0

Total area with bottom temperatures less than or equal to 0 celsius, in square kilometers

AVGBSBT_PLUSNW

Stratum-area weighted mean bottom temperature for EBS shelf standard and plusNW survey strata

AVGBSST_PLUSNW

Stratum-area weighted mean sea surface temperature for EBS shelf standard and plusNW survey strata

AVGBSBT_STANDARD

Stratum-area weighted mean bottom temperature for EBS shelf standard survey strata

AVGBSST_STANDARD

Stratum-area weighted mean sea surface temperature for EBS shelf standard survey strata

AVGBSBT_NBS

Stratum-area weighted mean bottom temperature for the NBS

AVGBSST_NBS

Stratum-area weighted mean sea surface temperature for the NBS

AVGBSBT_LT100M

Mean bottom temperature for EBS shelf stations at bottom depths < 100 m

AVGBSST_LT100M

Mean sea surface temperature for EBS shelf stations at bottom depths < 100 m

Source

https://www.fisheries.noaa.gov/contact/groundfish-assessment-program

afsc-gap-products/coldpool documentation built on Sept. 14, 2024, 7:40 p.m.