#5 The White Mountains, by John Christopher (Alien Invasion), young adult, but an absolute classic in the field. I read it, 4th grade, maybe fifth, and it was my favorite book for years.
#4 The Earth Abides, George R. Stewart (disease) how timeless is this book? When I bought it, it had a cover with a guy sporting an 80’s mullet. It wasn’t until the end of the book that I realised it had been written MUCH (1949).
#3 A Canticle for Lebowitz, Walter R. Miller Jr., (nuclear) beautifully written. Emotionally devastating. Nuclear holocaust books that call for an emotional investment that they never earn (On the Beach) are a dime a dozen. Canticle earns it.
#2 The Passage Justin Cronin (viral vampires), it couldn’t sustain it in the next two books, but the first book is a masterclass in the fast crash, end of the world as a disaster, run, run, run! fast paced action thriller. Wonderfully wrought characters.
#1 Lucifer’s Hammer Larry Niven/Jerry Pournelle (meteor strike)I don’t even think there’s a close second. This book simply gets everything right. The action, the characters acting in a realistic way, the plot threads that twist brilliantly before drawing to a satisfying conclusion. Largely forgotten now, It spawned a host of copycats in the literary field which in turn spawned a pair of Movies. This one is the gold standard!