Laureate 2020
Dr. Dorthe Dahl-Jensen
The Scientific Committee wrote in its recommendation:
We highly recommend Dr. Dorthe Dahl-Jensen for the Mohn Prize for her research and leadership in combining ice core data with models to reconstruct past climate and its impacts on the Greenland ice sheet and global climate, and applying this knowledge to understanding current and future rates of climate change and implications to sea-level rise.
Dr. Dahl-Jensen is Professor at the Niels Bohr Institute, University of Copenhagen, where she is a world leader in cryosphere science. She has led and developed the Centre for Ice and Climate (now Physics of Ice, Climate and Earth (PICE)) to world prominence as a key hub of climate research. Her and PICE's research have framed our knowledge of climate change providing key groundwork for understanding the ongoing anthropogenic perturbations of our climate system.
The ice core records, which have played a critical role in reconstructing the Earth's climate history, resulted from decades of collaborative research involving teams from Europe and America solving highly complex logistical problems and maintaining determined scientific efforts. Dahl-Jensen is widely recognised for her leadership in facilitating, developing and sustaining this complex effort in addition to her own research.
Excellence in research/development of ground-breaking new knowledge
Dahl-Jensen has worked primarily with the Greenland ice sheet, integrating ice physics and studies of the climate records obtained through analyses of ice cores. Her contributions and innovations are many. Of particular mention are: a) a groundbreaking paper published in Science, inverting ice core borehole temperature measurements to identify the true scale of ice age and Holocene temperature changes, thus opening up a new interpretation of water isotope measurements, traditionally the backbone of ice core climate studies; b) a series of studies of abrupt climate changes that forms the core of our knowledge about sudden high amplitude climate shifts and links the two poles; and c) her leadership in the quest to document the climate state and variability and associated sea level contributions during the last warm period (the Eemian interglacial).
Her diverse achievements range from studies of paleoclimate records to ice sheet and atmosphere dynamics, both on Greenland and in the Canadian Arctic (as well as in Antarctica). In addition to her seminal work on climate records, Dahl-Jensen has pushed the research frontier in terms of ice sheet physics and the role of water in their dynamics. She recently organized the EastGRIP ice core drilling campaign, a broad international effort to understand the physics of ice streams that form the main drainage of ice, which is critical to understanding how rapidly ice sheets and sea level will respond to future climate change.
Dahl-Jensen's work, published primarily in top journals with high impact, has received more than 20900 citations (over 8660 since 2014), with an h-index of 55. She has published with a large number of co-authors from many countries. She has been recognized in many ways, including as a recipient of the Louis Agassiz Medal, the EU Descartes Prize, the Vega Medal, the Amalienborg Award and the Munch Award. She has recently been awarded a prestigious Canada Excellence Research Chair (CERC) in "Arctic Sea Ice, Freshwater-Marine Coupling and Climate Change" at the University of Manitoba.
Recognized as a leader in her field
Dahl-Jensen's leadership entails both scientific leadership, leadership in organizing and executing complex logistical operations in the harsh environments on the summit of ice sheets, and leadership in organizing multinational collaboration to tackle scientific challenges through ice core drilling and analysis. In all three aspects she excels. She is extraordinarily well respected for her key role in bringing scientists from many countries to work together, to share results, resources and technologies and to generate scientific breakthroughs. She has mentored a suite of excellent scientists, now leaders in the field, and has created in PICE a centre of excellence that attracts the best talent internationally.
Highlight issues that are of particular relevance to the future development of the Arctic (and put these issues on the national/international agenda)
The Greenland ice sheet provides fundamental information about how the Arctic has responded to climate variations in the past. In particular, the high-resolution ice core data on the Eemian interglacial illuminates how the Greenland ice sheet may change in the future and influence the Arctic and the global climate of the 21st century and beyond.
Ice core programmes such as those organised and coordinated by Dahl-Jensen have given us critical insights into how melting of the ice sheet will influence the overall ocean circulation patterns (e.g., the thermohaline circulation), and, consequently, how sea ice distribution will respond to climate warming. A better understanding of former warm periods in the Arctic is absolutely essential to making better models for predicting future ice sheet loss and sea-level rise.
Dahl-Jensen's success in bringing policy makers and media actors to the Greenland ice sheet has greatly advanced public understanding of the complexities of the Earth’s climate system, and made important contributions to informed decision making.