Dan Hammarlund

My research is directed at increased understanding of natural climatic and environmental changes during specific intervals of the last glacial cycles as recorded in geological archives, such as lake sediments and peat deposits. Most of my projects involve the use of naturally occurring stable isotopes of oxygen (18O/16O), hydrogen (2H/1H), carbon (13C/12C), or nitrogen (15N/14N) as tracers of various aspects of climate and ecosystem development. Environmental isotope geochemistry is commonly integrated with palaeoecological methods for reconstruction of processes such as atmospheric circulation, local and regional vegetational change, hydrological variations, and biogeochemical interaction between lakes, terrestrial organic material and the atmosphere. I am especially interested in changes in the isotopic composition of precipitation, changing carbon cycling of lakes and wetlands, and alpine tree-limit fluctuations in response to large-scale climate dynamics. Most of my research focuses on Late Weichselian and Holocene climate changes in Scandinavia, particularly in the subarctic regions. I am also involved in studies of Quaternary environments along the arctic treeline in Eurasia and Canada, in the Mediterranean area, and on the Tristan da Cunha islands in the South Atlantic. I am actively involved in undergraduate teaching and graduate student supervision at the department.