46 Thermal Habitat Area

Description: Calculates the proportion of each EPU that exceeds temperature thresholds as a daily time series from 1993 – 2023

Indicator family:

Contributor(s): Joe Caracappa

Affiliations: NEFSC

46.1 Introduction to Indicator

See “Thermal Habitat Persistence” for cell-based calculations. Many deep water benthic and demersal exhibit thermal preferences for metabolic, reproductive, and growth processes. Temperatures above these thermal presences may impair these processes. Two temperature thresholds (15 and 24 degrees C) were chosen based on cutoff points where demersal species are less commonly found. Thermal habitat area is calculated by identifying 1/12 degree cells within a given EPU that are greater than or equal to the temperature threshold then taking the sum of all cell areas. Data from 1993-01-01 to 2023-08-29 were obtained from the CMEMS’ GLORYS12V1 global reanalysis product, and from 2023-08-30 to 2023-12-31 data were obtained from the CMEMS’ PSY global forecasting product.

46.2 Key Results and Visualizations

For each EPU, bottom temperature data were separate by depth bin (0-25m; 25m-100m; and >100m), as well as temperature threshold (>15C , >24C), and the proportion of each EPU exceeding these thresholds was calculated on a daily basis from 1993 to 2023. Overlayed time series of each year’s proportional area shows that recent years have resulted in a increasing proportion of the MAB and GB mid-depths have experienced high temperatures. The 24C threshold is rarely seen in GB and GOM.

46.2.1 MAB

46.2.2 GB

46.2.3 GOM

46.3 Indicator statistics

Spatial scale: EPU

Temporal scale: daily

Synthesis Theme:

46.4 Implications

If a large proportion of species current habitat become thermally inhospitable, it can influence species productivity and in extreme cases cause mortality.

46.5 Get the data

Point of contact:

ecodata name: ecodata::thermal_habitat_area

Variable definitions

Source: GLORYS (CMEM’s GLORYS12V1 global reanalysis bottom temperature) and PSY (CMEM’s PSY global forecast bottom temperature)

min.depth: minimum of depth band max.depth: maximum of depth band

temp.threshold: cutoff temperature for thermal area calculations (all areas greater than or equal to this temperature)

area: area exceeding temperature threshold (m2) area.prop: proportion of EPU area exceeding temperature threshold

Indicator Category:

46.6 Public Availability

Source data are publicly available.

46.7 Accessibility and Constraints

No response

tech-doc link https://noaa-edab.github.io/tech-doc/thermal_habitat_area.html