PRODUCT USER MANUAL (PUM)

Marine heat wave indices


Definition

Marine heat wave (MHW) indices have been defined to estimate sub-regional changes in MHW characteristics over the last four decades, as follows:
  • [MHW mean intensity]: annual mean of MHW intensity above the threshold (fixed as the climatological 90th percentile)
  • [MHW maximum intensity]: annual maximum of MHW intensity
  • [MHW mean duration]: annual mean of MHW duration
  • [MHW frequency]: annual number of discrete events
  • [MHW total days]: annual total number of MHW days
  • Visualization

    Every annual parameter is computed from the MHWs as detected using the Copernicus Marine Service satellite SST products. This section provides figures about:
  • Annual state in 2021 (2D map in the Mediterranean Sea)
  • Sub-regional interannual and decadal variability over the period 1982-2021 (time series and associated statistics)
  • Mean and linear trend over the period 1982-2021 (2D maps in the Mediterranean Sea).

  • MHW mean intensity

    Annual state (2021): map of annual mean intensity in the Mediterranean Sea


    Sub-regional interannual/decadal variability (from 1982 to 2021): timeseries of annual mean intensity (left) and associated statistics (right) in sub-regions
    Mean and trend (1982-2021): maps of mean and linear trend of mean intensity in the Mediterranean Sea

    MHW maximum intensity

    Annual state (2021): map of annual maximum intensity in the Mediterranean Sea


    Sub-regional interannual/decadal variability (from 1982 to 2021): timeseries of annual maximum intensity (left) and associated statistics (right) in sub-regions
    Mean and trend (1982-2021): maps of mean and linear trend of maximum intensity in the Mediterranean Sea

    MHW mean duration

    Annual state (2021): map of annual mean duration in the Mediterranean Sea


    Sub-regional interannual/decadal variability (from 1982 to 2021): timeseries of annual mean duration (left) and associated statistics (right) in sub-regions
    Mean and trend (1982-2021): maps of mean and linear trend of mean duration in the Mediterranean Sea

    MHW frequency

    Annual state (2021): map of annual number of events in the Mediterranean Sea


    Sub-regional interannual/decadal variability (from 1982 to 2021): timeseries of annual number of events (left) and associated statistics (right) in sub-regions
    Mean and trend (1982-2021): maps of mean and linear trend of number of events in the Mediterranean Sea

    MHW total days

    Annual state (2021): map of annual total days in the Mediterranean Sea


    Sub-regional interannual/decadal variability (from 1982 to 2021): timeseries of annual total days (left) and associated statistics (right) in sub-regions
    Mean and trend (1982-2021): maps of mean and linear trend of MHW total days in the Mediterranean Sea