Marine heatwave (MHW) standard detection methods use a fixed baseline, showing rising MHW frequency and intensity due to global warming. To address this, alternative approaches separate long-term warming from extreme events. Here we compare two in the Balearic Sea: a moving baseline and detrended data. From 1982 to 2023, we found a warming trend of 0.036 °C per year, with major MHWs in 2003 and 2022 identified by all methods. Only the fixed baseline shows rising MHW duration and intensity.