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State-of-the-art climate models were used to simulate climate conditions in Europe during Greenland Stadial (GS) 12 at 44 ka BP. The models employed for these simulations were: (i) a fully coupled atmosphere-ocean global climate model (AOGCM), and (ii) a regional atmospheric climate model (RCM) to dynamically downscale results from the global model for a more detailed investigation of European climate conditions. The vegetation was simulated off-line by a dynamic vegetation model forced by the climate from the RCM. The resulting vegetation was then compared with the a priori vegetation used in the first simulation. In a subsequent step, the RCM was rerun to yield a new climate more consistent with the simulated vegetation. Forcing conditions included orbital forcing, land-sea distribution, ice-sheet configuration, and atmospheric greenhouse gas concentrations representative for 44 ka BP. The results show a cold climate on the global scale, with global annual mean surface temperatures 51C colder than the modern climate. This is still significantly warmer than temperatures derived from the same model system for the Last Glacial Maximum (LGM). Regional, northern European climate is much colder than today, but still significantly warmer than during the LGM. Comparisons between the simulated climate and proxy-based sea-surface temperature reconstructions show that the results are in broad agreement, albeit with a possible cold bias in parts of the North Atlantic in summer. Given a prescribed restricted Marine Isotope Stage 3 ice-sheet configuration, with large ice-free regions in Sweden and Finland, the AOGCM and RCM model simulations produce a cold and dry climate in line with the restricted ice-sheet configuration during GS 12. The simulated temperature climate, with prescribed ice-free conditions in south-central Fennoscandia, is favourable for the development of permafrost, but does not allow local ice-sheet formation as all snow melts during summer. Marine Isotope Stage 3 (MIS 3) was characterized by recurrent and abrupt changes from cold stadial to milder interstadial conditions, followed by a slower return to stadial conditions (Dansgaard et al. 1993). These cycles, known as Dansgaard-Oeschger cycles, are recorded in Greenland ice cores (e.g. North GRIP members 2004) and in temperature proxies from oceanic areas at low and high latitudes in both hemispheres (see review by Clement & Peterson 2008). Qualitative, proxy-based information for Dansgaard-Oeschger cycles is also registered in land records (e.g. Wohlfarth et al. 2008;Wohlfarth 2010), but their often poor chronological control and lack of quantitative data limit detailed comparisons.The large ice sheet covering Fennoscandia during the Last Glacial Maximum (LGM, 21 ka BP) eroded most of the sequences that could have provided palaeoclimatological information for MIS 3. The scarcity of regional palaeodata for MIS 3 and earlier periods leads to large uncertainties regarding, for example, the extent of earlier ice sheets and permafrost, and the length of icef...

Abstract. Few hydrological studies have been conducted in Greenland, other than on glacial hydrology associated with the ice sheet. Understanding permafrost hydrology and hydroclimatic change and variability, however, provides key information for understanding climate change effects and feedbacks in the Arctic landscape. This paper presents a new, extensive, and detailed hydrological and meteorological open access data set, with high temporal resolution from a 1.56 km 2 permafrost catchment, with a lake underlain by a through-talik close to the ice sheet in the Kangerlussuaq region, western Greenland. The paper describes the hydrological site investigations and utilized equipment, as well as the data collection and processing. The investigations were performed between 2010 and 2013. The high spatial resolution, within the investigated area, of the data set makes it highly suitable for various detailed hydrological and ecological studies on catchment scale. The data set is available for all users via the PANGAEA database, http://doi.pangaea.de/10.1594/PANGAEA.836178.