Project C3

Assessing land-atmosphere heat and CO2 exchange with Eddy covariance

Complementary Chinese topic: Analysis of land surface parameters and heat fluxes

Research objectives

The objectives of this project are to (1) quantify the energy balance between permafrost and atmosphere, (2) quantify the C exchange between soil, vegetation, and atmosphere and derive rates of photosynthesis and soil respiration, and (3) identify the dominant meteorological drivers of the ecosystem-atmosphere exchange on various time scales.

Using wavelet analysis to be able and account for transitions during the observation period, we will analyze which variables explain the heat and C fluxes on time scales ranging from hours to weeks, months, and seasons. Wavelet coherence, in addition, allows for testing correlations between signals in the time and frequency domain and their phase shift is a meaningful criterion for a potential cause-and-effect relationship, thereby improving our mechanistic understanding of ecosystems processes and informing model development. This deeper analysis of measured fluxes will focus on CO2 and meteorological drivers on the German side, whereas the complimentary Chinese project will focus on heat fluxes and relevant land surface parameters.

Sino-German complementarity of research

Together with our Chinese partners, we will install and continuously operate an eddy covariance flux tower at Nam Co whose footprint will ideally cover study sites of projects C1 and C2 as well the complimentary Chinese partner project "Methane fluxes and their response to global climate change". In phase 1, the measurements will focus on latent and sensible heat flux and the exchange of CO2, with CH4 envisioned being included in phase 2.

Supervisors:

Jun.-Prof. Dr. Torsten Sachs, TU Braunschweig, GFZ Potsdam
Prof. Dr. Georg Guggenberger, LU Hannover
Prof. Dr. Ma Yaoming, ITP