Room 813, 8th Floor The Jockey Club Tower, Centennial Campus, HKU
Revisiting the Medieval Climate Anomaly in the Scandinavian Mountains
Professor Hans Linderholm
About the Speaker:
Dr. Hans Linderholm is a Professor in Physical Geography and the Director of the Gothenburg University Laboratory for Dendrochronology (GULD), as well as co-director of the Sino-Swedish Tree-Ring Research Centre (SISTRR). He has been co-chair of the CLIVAR/PAGES Intersection Working Group (2012-2014), leader of the PAGES Arctic2k project (2015-2017), and currently co-ordinates the PAGES 2k phase III project. He has served on several international and national committees and boards, including the Terrestrial Working Group, International Arctic Science Committee, and the organizing and scientific (chair) committees of the 10th International Conference of Dendrochronology. He is Editor-in-Chief of the international journal Geografiska Annaler A, Editor of Climate of the Past, and was a contributing author of the Arctic Climate Impact Assessment (2005). Dr. Linderholm’s research is focused on climate variability from the past (last 2000 years) to the future (next 100 years), especially high-latitude and altitude regions, including the Arctic and the Tibetan Plateau. He also studies the effect of climate change on terrestrial and marine ecosystems, and the role of the large-scale circulation in the oceans and atmosphere on climate variability, climate change and human health.
The Medieval climate anomaly (MCA, ca 900-1200 CE) is an important period which regionally has been inferred to as an analogue to the present, at least in terms of summer temperatures. Thus, there is a potential to use the MCA to study regional responses of the climate system to above normal temperatures. However, due to decreasing quantity (and sometimes quality) of high-resolution data, such as tree rings, back in time, there are considerable uncertainties regarding MCA temperatures in many regions. Here we revisit one of the most well studied tree-ring sites in the northern high-latitudes: the central Scandinavian Mountains, where research has been ongoing for more than 20 years. Based on recent sampling of unique tree-ring data across the MCA, we present a revised, better replicated and less uncertain reconstruction of April-August temperatures. We show that warm-season temperatures during the MCA previously inferred as being as high, or higher, than the present, likely were lower. The strong regeneration pulse that occurred during the 1200s, preceding the transition to the Little Ice Age, is also discussed.
Recent development of Tourism Geography inside and outside China
Professor Xu Honggang
About the Speaker:
Professor Xu is the Dean of School of Tourism Management, Sun Yat Sen University. She obtained PhD from Asian Institute of Technology, Thailand. She obtained Roy Wolfe Award from Tourism commission of American Geography Association for contribution in tourism geography researches. She is key expert in UNWTO sustainable tourism monitor center (MCSTO). She serves as the editorial board in several tourism journals, such as Tourism Management, Journal of Sustainable Tourism and Mobilities. She is also associate editor of Tourism Geographies. She is the team leader and key members in National criteria of ecotourism tourism attractions, National criteria of demonstration cities of leisure，National criteria of Wetland tourism and National criteria of wellness tourism.
With the development of tourism, not only more and more geographers began to examine the phenomenon of tourism, many scholars from other disciplines also use the geographical theories and methods to address tourism studies. Tourism geography gradually becomes a main sub-discipline in the discipline of geography. This presentation would address a few main issues of tourism geographies studies in mainland China and internationally, including the key research topics in tourism geographies, the debates of relationships between tourism geographies and main stream geographies, tourism geographies studies in mainland China. The presentation also attempts to discuss some future potentials for tourism geography studies.
All are welcome