evidence: In this era of rapid human-caused climate change, the setting of new regional and national temperature records during heatwaves happens so frequently that it can sometimes feel commonplace. [...] Other record-shattering heat events from recent years include a year-long marine heatwave in the north Atlantic Ocean beginning in March 2023, when sea surface temperatures were up to 5C hotter than normal. [...] The research found that, under the scenario of very high greenhouse gas emissions, week-long heat events that break records by three or more standard deviations will be come between two and seven times more likely in the period 2021-50 and three-to-21 times more likely in the period 2051-80, when compared to the past three decades.