Cave records from Southeast Asia: Windows to Past Hydroclimate Variability
About Dr. Michael Griffiths
Dr. Griffiths specializes in the use of geochemical tracers [i.e. oxygen and carbon isotopes, and trace elements (Mg, Sr, Ba)] preserved in cave carbonate deposits (speleothems) to reconstruct past environmental and climatic changes in monsoonal Asia. Dr. Griffiths received his Ph.D. from the University of Newcastle, Australia, where he worked on a large collaborative project focused on building new records of Indo-Australian monsoon variability during the last glacial cycle from deposits in unexplored cave systems in east Indonesia. Following graduation in 2010, he was awarded a NOAA/UCAR Climate and Global Change fellowship at UC Irvine to work on novel speleothem records from Laos, where he has continued to work since beginning his academic position at William Paterson University.
About the Seminar
Despite significant advances in our understanding of tropical Australasian monsoon climate variability over the past decade(s), we still know very little about the range and mechanisms of rainfall variability in Southeast Asia on orbital (~100,000-year) to millennial (~1000-year) timescales. As a result, state-of-the-art general circulation models (GCMs) have little data with which to validate simulations of past climate, thereby placing much uncertainty on future projections of monsoon (i.e. rainy season) variability with global warming. Given the large population of inhabitants in Indochina that rely on the monsoon rains for agricultural and economic development, it is of utmost importance that we gain a better understanding on the factors that influence the monsoon climate. Over the past 6 years, my colleagues and I have spent time exploring cave systems in remote regions of Laos, installing data-loggers and collecting stalagmites, with the overarching goals being to: i) better constrain modern processes controlling speleothem growth and in particular how they preserve above-cave climate changes; and ii) to build high-resolution and long records of past monsoon behavior from the geochemical signals preserved in these deposits. In this talk, I will discuss the utility of speleothems to accurately preserve past changes in regional SE Asian hydroclimate, and their strong potential in addressing current uncertainties in tropical climate variability over a range of timescales (i.e. glacial-interglacial to millennial), particularly with respect to how the Asian monsoon responded to past changes in Earth’s boundary conditions.