PRODUCT USER MANUAL (PUM)

Marine heat waves



Marine heat waves [MHW] occur when ocean water temperatures are much warmer than normal (above the 90th percentile of the climatological distribution and so-called marine heat spikes [MHS]) for at least five consecutive days (Hobday et al., 2016). The MHWs are computed using sea surface temperature (SST) from the daily near real-time (1/16º) and reprocessed (1/20º) satellite products in the Mediterranean Sea distributed by the Copernicus Marine Service (Pisano et al., 2016, Buongiorno Nardelli et al., 2013). The reference period chosen for the climatology is 1982-2015.
  • The daily bulletin provides daily map of MHS in the Mediterranean (for the last available day) and time series of sub-regional SST and MHS over the current year.
  • Annual MHW indices have been defined to estimate the long-term evolution of sub-regional MHW characteristics over the last four decades: total days, mean amplitude, maximum intensity, mean duration and frequency.

  • Daily bulletin

    Map of daily marine heat spike w.r.t. the daily 90th percentile climatology for the last available day (left). Timeseries of the sub-regional daily SST for the current year, the daily mean and 90th percentile climatologies, with marine heat spikes highlighted (right).

    Marine heat wave indices (1982-2022)

    MHW total days

    Map of the annual MHW total days in 2022 (left) and time series of the sub-regional annual total days from 1982 to 2022 (right)

    MHW mean amplitude

    Map of the annual MHW mean amplitude in 2022 (left) and time series of the sub-regional annual mean amplitude from 1982 to 2022 (right)

    MHW maximum intensity

    Map of the annual MHW maximum intensity in 2022 (left) and time series of the sub-regional annual maximum intensity from 1982 to 2022 (right)

    MHW mean duration

    Map of the annual MHW mean duration in 2022 (left) and time series of the sub-regional annual mean duration from 1982 to 2022 (right)

    MHW frequency

    Map of the annual MHW frequency in 2022 (left) and time series of the sub-regional annual frequency from 1982 to 2022 (right)