Cosy catastrophe
Cosy catastrophe is the name given to a style of post-apocalyptic science fiction that was particularly prevalent after the Second World War and among British sf writers.
The term was coined by Brian Aldiss in Billion Year Spree: The History of Science Fiction. Whether it is used affectionately or not generally depends on whether the reader regards a degree of old-fashioned Englishness as either quaint or stuffy.
A "cosy catastrope" is typically one in which civilisation (as we know it) comes to an end and everyone is killed except for a handful of middle-class survivors, who then set about rebuilding their version of civilisation. Some critics note that the characters are typically WASPs (White Anglo-Saxon Protestants)
English author John Wyndham is, perhaps unfairly, the figure most closely associated with the genre; while several of his novels may qualify (particularly, The Day of the Triffids), his writing had more imagination than the label generally suggests.
A later example of the genre was the 1970s British television serial Survivors, created by Terry Nation.