Heatwave indexes 1980-2018

<p>Heatwaves were defined as minimum temperature exceeding the 99th percentile of minimum temperature for the reference period (1986-2005) for four or more days.</p> <p>From this definition, four heatwave indicators are derived:</p> <p>Number of heatwave instances</p> <p>Total number of days of heatwave</p> <p>Heatwave degree-days over threshold, being the sum of the differences between the daily temperatures and the 99th percentile threshold</p> <p>Mean length of heatwaves</p> <p>Heatwave&nbsp; mean degrees over threshold, being the heatwave degree-days divided by the total number of days.</p> <p>&nbsp;</p> <p>These definitions were applied to ECMWF ERA5 temperature data at 0.5˚ grid resolution for the years 1980-2018. Each indicator is provided in a separate file.</p> <p>&nbsp;</p>