Research

My research is broadly focussed on the global carbon cycle, especially using the vantage point from space (or air) to obtain a truly global (or regional) view on specific phenomena occuring at the interfacce between the Earth Surface (including terresial biosphere and anthropogenic activities) and the atmosphere. My current focus is on the study of solar induced chlorophyll fluorescence as well as atmospheric methane and carbon dioxide. Several more specific projects are listed below:

Chlorophyll Fluorescence Studies

Ground-based studies of fluorescence

Funded by the Keck institute and JPL, we are building a small ground-based network of chlorophyll fluorescence imaging spectrometers. These will be deployed at flux-tower sites in 2016 and research will focus on the relationship between chlorophyll fluorescence (SIF) and carbon exchange measured by flux-towers.

Chlorophyll Fluorescence Imaging Spectrometer

Fluorescence Imaging

The airborne Chlorophyll Fluorescence Imaging Spectrometer (CFIS) was built at JPL for OCO-2 validation purposes. It is a high-resolution imaging spectrometer, which we optimized for remote sensing of chlorophyll fluorescence. Studies of several flight campaigns over flux-towers and OCO-2 orbit tracks are ongoing.

OCO-2

OCO-2 Remote Sensing of CO2 and Fluorescence

The Orbiting Carbon Observatory-2 (OCO-2) is a 3-channel grating spectrometer optimized for remote sensing of CO2 using two near-infrared absorption bands and one oxygen channel. Our special interest is in the joint study of CO2 fluxes and chlorophyll fluorescence on a global scale.

Methane Remote Sensing

Remote Sensing of Methane

We use both satellites (SCIAMACHY, GOSAT, TROPOMI) as well as airborne data (AVIRIS-NG) to study the global and regional budgets of the 2nd most important anthropogenic greenhouse gas.