Both "hot days" and heatwaves are being defined by temperatures that exceed some arbitrary threshold (in this case the 95 percentile of the long-term record). Obviously, if it is getting hotter one expects that the frequency of passing any threshold temperature will increase. While it is catchy to say that "the length of summer heat waves over Western Europe has doubled and the frequency of hot days has almost tripled", it doesn't actually tell us much since it depends on picking a particular arbitrary threshold. In other words, there is no inherent jusitification for why 5% of days are considered "extremely hot" rather than 2% or 10%.
I'm not saying the research isn't useful (I assume it is), but the "hook" being given by the media is not really a scientifically meaningful statement, especially when one removes the context of what "hot day" was defined to mean. -Robert A. Rohde http://www.globalwarmingart.com/ On Aug 4, 10:45 am, Phil Randal <[EMAIL PROTECTED]> wrote: > BBC News reports today that the duration of heatwaves in Western > Europe has doubled since 1880. > > http://news.bbc.co.uk/1/hi/sci/tech/6929668.stm > > "The authors of the research also discovered that the frequency of > extremely hot days has nearly tripled in the past century. > > The study shows that many previous assessments of daily summer > temperature change underestimated heatwaves in Western Europe by about > 30%. > > The research appears in the Journal of Geophysical Research - > Atmospheres. > > The team found that heatwaves lasted an average of three days now, > with some lasting up to 13 days. This compares with an average of > about 1.5 days in 1880. " > > The article's behind a paywall, but the abstract can be found here: > > http://www.agu.org/pubs/crossref/2007/2007JD008510.shtml > > Phil --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups Global Change ("globalchange") newsgroup. Global Change is a public, moderated venue for discussion of science, technology, economics and policy dimensions of global environmental change. Posts will be admitted to the list if and only if any moderator finds the submission to be constructive and/or interesting, on topic, and not gratuitously rude. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/globalchange -~----------~----~----~----~------~----~------~--~---
