8 Marine Heatwaves
Description Marine heatwaves (MHW) occur when ocean temperatures are much warmer than usual for an extended period of time; they are specifically defined by the difference between the current temperature and the expected temperature for a specific location and time of year [1]. MHWs are a growing field of study worldwide because of their effects on ecosystem structure, biodiversity, and regional economies.
Indicators
Marine Heat Wave Heatwave Cover
- Component Category: Climate and Ocean Drivers
- Time Range: 1982 - 2025
- CCIEA Data Contact: andrew.leising@noaa.gov
- Institution: NOAA/SWFSC/ERD
- Source Data: Marine heatwaves, or MHWs, occur when ocean temperatures are much warmer than usual for an extended period of time; they are specifically defined by differences in expected temperatures for the location and time of year. MHWs are a growing field of study worldwide because of their effects on ecosystem structure, biodiversity, and regional economies. Developed by oceanographers from NOAA Fisheries’ Southwest Fisheries Science Center as an experimental tool for natural resource managers, the California Current MHW Tracker is a program designed to understand, describe, and provide a historical context for the 2014-16 blob. It also produces a range of indices that could help forecast or predict future MHWs expected to impact our coast.
Marine Heat Wave Maximum Area
- Component Category: Climate and Ocean Drivers
- Time Range: 1982 - 2025
- CCIEA Data Contact: andrew.leising@noaa.gov
- Institution: NOAA/SWFSC/ERD
- Source Data: Marine heatwaves, or MHWs, occur when ocean temperatures are much warmer than usual for an extended period of time; they are specifically defined by differences in expected temperatures for the location and time of year. MHWs are a growing field of study worldwide because of their effects on ecosystem structure, biodiversity, and regional economies. Developed by oceanographers from NOAA Fisheries’ Southwest Fisheries Science Center as an experimental tool for natural resource managers, the California Current MHW Tracker is a program designed to understand, describe, and provide a historical context for the 2014-16 blob. It also produces a range of indices that could help forecast or predict future MHWs expected to impact our coast.
Marine Heat Wave Maximum Intensity
- Component Category: Climate and Ocean Drivers
- Time Range: 1982 - 2025
- CCIEA Data Contact: andrew.leising@noaa.gov
- Institution: NOAA/SWFSC/ERD
- Source Data: Marine heatwaves, or MHWs, occur when ocean temperatures are much warmer than usual for an extended period of time; they are specifically defined by differences in expected temperatures for the location and time of year. MHWs are a growing field of study worldwide because of their effects on ecosystem structure, biodiversity, and regional economies. Developed by oceanographers from NOAA Fisheries’ Southwest Fisheries Science Center as an experimental tool for natural resource managers, the California Current MHW Tracker is a program designed to understand, describe, and provide a historical context for the 2014-16 blob. It also produces a range of indices that could help forecast or predict future MHWs expected to impact our coast.
Additional Information
There is growing recognition that marine heatwaves can have strongly disruptive impacts on the CCE (Morgan et al. 2019). Based on an analysis of sea surface temperature anomalies (SSTa) obtained from satellite measurements (OISST); we define marine heatwaves as 1.0 times when normalized SSTa >1.29 s.d. (90th percentile) of the long-term SSTa time series at a location, and 2. lasts for >5 days; which are analogous to the thresholds suggested in Hobday et al. (2016). Here, we further report on statistics concerning large heatwaves (LHW) which were tracked through space and time, with LHW defined as those heatwaves with an area > 400,000 km2 (these denote the top 20% of all heatwaves by area as measured since 1982 when satellite data became available for tracking.
The underlying climatology used for SST anomaly analysis has changed from 1982-2010, to now encompass 1982-2020; hence small changes in the retrospective analysis of tracked heatwaves reported more recently as compared to previous reports.
Indicator Download
ERDDAP™ link:
https://oceanview.pfeg.noaa.gov/erddap/tabledap/cciea_OC_MHW.html
References