My research primarily involves the use of geochemical variations preserved in cave-calcite deposits (speleothems) to reconstruct time-series of past environmental changes. A major goal of my research is to improve our understanding of what fundamentally controls speleothem stable isotopic composition and trace-element composition at both short and long timescales (seasonal to glacial-interglacial scale). These proxies are primarily controlled by variations in temperature and/or rainfall at a particular study area, but the specific mechanisms are complicated, incorporating a range of atmospheric, hydrologic, biologic, pedologic, kinetic, crystallographic, and thermodynamic controls. To understand these controls, I combine detailed studies of modern cave systems with studies of fossil speleothems, utilizing a wide range of analytical techniques (e.g. microsampling, analytical chemistry, mass spectrometry, laser ablation, etc.) along with laboratory experiments, rigorous data analysis, and geochemical modeling. Speleothem records can be dated much more precisely than most other paleoclimate archives using U-series methods, and therefore, often provide important information about the relative timing and mechanisms of abrupt climate change. The ultimate goal of my research is to obtain precisely dated, high-resolution, quantitative reconstructions of past variations in rainfall and temperature at a wide range of timescales.

Our goal is to understand the role that ocean dynamics and thermodynamics plays on the climate system.

In particular, we study how phenomena that are well localized in space and time (as tropical cyclones, deep convection, oceanic eddies) globally influence the distribution of energy on our planet. Once those mechanisms and their feedbacks on the climate system are understood, their relevance can be quantified and their role can be parameterized in larger scale models. Our main focus is on the physical characteristics of the ocean and climate system.

We seek to improve our understanding of global change in terrestrial ecosystems. We use remote sensing data, atmospheric trace gas observations, field measurements, and models in new ways to study feedbacks between terrestrial ecosystems and climate.

My research program is centered on space-based climate measurements with particular attention to cryospheric and high latitude regional studies.

I am interested in studying processes of global change using various remote sensing techniques, as well as lithospheric properties and loading processes on geological timescales.

Our research group studies the energy and trace species that pass through Earth's atmosphere. We model the microphysics of trace gas, aerosol, cloud, and surface interactions with Earth's radiative, thermodynamic, and chemical budgets. We then (often) parameterize these effects in climate models. The model simulations, combined with lab, field, and satellite data, help us attribute alteration of Earth's climate and composition to specific processes. Our current research includes mineral dust, meteoric, and carbonaceous aerosols, snow lifecycle and albedo, aerosol impacts on ocean biogeochemistry, wind-driven surface energy/mass exchange, climate-disease links, and terascale data analysis. Our aerosol generation, radiative transfer, and data processing models are freely available and are used in geoscience research institutions world-wide.