<Research Outline (Background, Objectives, Methods, etc)>
The reconstruction of paleotemperature is critical for understanding past climate change and thereby improving predictions of future change in both atmospheric and aquatic environments. The unsaturation index of alkenones, which were discovered in marine sediments about 40 years ago, has frequently been used for the reconstruction of paleotemperature in the surface ocean, where alkenone-producers, namely haptophyte algae, grow.
In recent decades, the Brown University (USA) group have studied alkenones in Greenlandic, US, and Canadian lakes, and have elucidated many mysteries of lacustrine alkenones. The Shiraiwa Group (University of Tsukuba, Japan) has collaborated with Prof. Toney, PhD from Brown University and now at the University of Glasgow (UK), and succeeded in finding alkenone-producing algal species in Canadian lakes and isolating new alkenone-producing strains, which are now identified as haptophytes (Organic Geochemistry 2018).
Recently, the Shiraiwa Group in Tsukuba developed genetic transformation techniques for alkenone-producing haptophytes and also identified the genes and enzymes contributing to the desaturation reaction of alkenones that cause their temperature-dependency (Scientific Reports 2018). The information and technique will be useful for elucidating biosynthetic and regulatory mechanism on temperature-recording in alkenone molecules.
Prof. D’Andrea’s research is geared toward understanding global climate change, including current anthropogenic driven changes and past changes to the Earth System. He investigates the natural modes and underlying forcing mechanisms of past climate variability, with the goal of developing a better understanding of how the Earth System responds to natural and human-induced perturbations. To achieve this, he is also focusing on the climate change in the Arctic region, one of important areas for global climate change now.
Under such circumstances, we believe that discussions among these research groups specialized in different disciplines of research will be valuable for making a strategy of how future research on the alkenone paleothermometry can improve our understanding of the rapidly changing world.
The purpose of this USJI research project is to discuss the current status of alkenone paleothermometry in the reconstruction of paleotemperature and how to best direct future research efforts on ‘The Alkenone Molecular Thermometer’ in a manner that most effectively addresses outstanding climate questions that concern paleotemperature of the oceans and inland lakes. The main point/target of this research project is to discuss how to increase the accuracy and reliability of the alkenone paleothermometer and how to use it for future projections of global climate change, in the Arctic and other climate sensitive regions.
(1) We will discuss how to solve unknown regulatory mechanisms still remaining with ‘the Alkenone Molecular Thermometer’ by exchanging information among the scientists nominated above (~December, 2018).
(2) We will discuss the possibility of how we will be able to promote alkenone research by the collaboration of algal physiologists, biogeochemists, environmental researchers, and ecosystem researchers (~February, 2018).
Based on the achievements of (1) and (2), we will discuss using the USJI Voice (~March, 2019).