<P> The effects of summer heat and rainfall patterns are real, but vary by latitude and location according to many factors . For example, London, UK is farther north than Calgary, Canada, but has a milder climate from the presence of the sea and the warm Gulf Stream current . A medical institution has reported a connection between Finland's dog days and increased risk of infection in deep surgery wounds, although that research remains unverified . </P> <P> It is possible that the Roch, the legendary medieval patron saint of dogs celebrated by the Catholic Church on 16 August, owes some of his legacy to the dog days . From the period of his self - proclaimed protectorate over the island, the Danish adventurer Jørgen Jürgensen is remembered in Iceland as Jorgen the Dog - Day King (Icelandic: Jörundur hundadagakonungur). </P> <P> In western literature, apart from the Greek and Roman works mentioned above, the dog days appear in John Webster's 1613 play The Duchess of Malfi, Charles Dickens' 1843 novella A Christmas Carol, R.H. Davis' 1903 short story "The Bar Sinister", J.M. Synge's 1909 poem "Queens", and Richard Adams's 1972 novel Watership Down . They feature in the children's novels Tuck Everlasting (1973). and Dog Days (2009). </P> <P> In film, the titles of Dog Day Afternoon (1975) and Hundstage (German for "Dog Days"; 2001) evoke their oppressive seasonal settings . </P>

Where did the phrase dog days of summer come from