A _GUARDIAN _'TOP 10 NATURE MEMOIRS' PICK 'POETIC AND HEARTFUL' _GUARDIAN_ Icelandic author and activist Andri Snær Magnason's 'Letter to the Future', an extraordinary and moving eulogy for the lost Okjökull glacier, made global news and was shared by millions. Now he attempts to come to terms with the issues we all face in his new book On Time and Water. Magnason writes of the melting glaciers, the rising seas and acidity changes that haven't been seen for 50 million years. These are changes that will affect all life on earth. Taking a path to climate science through ancient myths about sacred cows, stories of ancestors and relatives and interviews with the Dalai Lama, Magnason allows himself to be both personal and scientific. The result is an absorbing mixture of travel, history, science and philosophy.