Istidens oppdager – Jens Esmark, pioneren i Norges fjellverden
Published by Kagge Forlag, 2017

Jens Esmark is the great pioneer in the exploration of Norway’s mountain world in early 19th century,  and this is the definitive story of his life, his expeditions, mountain ascents and glacier crossings. Not the least the book traces the paths to his epochal discovery of ice ages, the most dramatic climate changes on Earth. As Esmark’s supporters or opponents we meet a rich gallery of Norwegian and foreign students and colleagues. The book is compulsory reading for all mountain hikers and nature enthusiasts, and everyone with an interest in Norwegian and European cultural history.

The Press wrote:
“A biography that should appeal to a wide audience of nature-interested readers, at a time when the climate debate is relevant like never before.”

“In mid-September 1823, an elderly professor and his two young students returned to Christiania after three months of travel in Norway. Along the way they had stumbled upon the biggest scientific discovery ever made in Norwegian nature: They had discovered the ice age.” This is how Geir Hestmark begins the book that he has spent twelve years researching and writing. Those who do not want to keep on reading cannot be much curious because you feel like you are sitting with a novel in your hands, not a biography. …The book is a pleasure to read.”
Geo 365

The book is nominated to best non-fiction book in Norway since 2000, one out of ten.

Geir Hestmark (b. 1958) graduated in both philosophy and natural science, and is currently a professor at the University of Oslo and a Fellow of the Norwegian Academy of Science. He has contributed to Thinkers of the West (1994), Norwegian History of Non-Fiction Literature (1998), Norwegian History of Ideas (2002), and Norwegian Polar History (2004). For his biography of Waldemar C. Brøgger, Science and Nation he received the Freedom of Speech Honors Prize in 2000.