modern laser-optical analysers (Photo: Alfred-Wegener-Institut) Health and safety instructions at the ISOLAB - Stable Isotope Laboratory Potsdam (Photo: Alfred-Wegener-Institut) When analysing the water isotopes [...] (Photo: Alfred-Wegener-Institut) View into the laser fluorination: The samples to be analysed are illuminated with the laser beam in the right-hand part of the apparatus (Photo: Alfred-Wegener-Institut) [...] isotopes, 48 water samples are measured one after the other (Photo: Alfred-Wegener-Institut) When scientists talk about climate archives, they don't have a real book or a library in mind. Instead, they