Subventions et des contributions :

Subvention ou bourse octroyée s'appliquant à plus d'un exercice financier. (2017-2018 à 2022-2023)

Understanding and predicting the fluxes of greenhouse gases (GHG) between the Earth’s surface and the atmosphere is key to quantify climate-relevant processes and feedbacks in global biogeochemical cycles, and assess future climate change. Much of our current understanding on the role of land surface processes and feedbacks on GHG exchange is based on global inverse models or direct measurements of fluxes using the eddy covariance (EC) method. However, the EC method is generally limited to areas that are homogeneous.
The long-term vision of the proposed programme is to advance and integrate observational and modelling methods to quantify and attribute GHG fluxes also over heterogeneous and frequently changing ('transient') landscapes . In terms of knowledge generation, we will assess the role of previously neglected landscapes, namely river deltas, intertidal zones, and systems that are controlled by multiple exchange processes simultaneously (e.g. cities). From a technical perspective, the programme will develop, expand and test new micro- and boundary-layer methods to overcome challenges of quantifying and attributing GHG fluxes in time and space over heterogeneous and transient land surfaces. Three methodologically driven goals are defined that are transferrable and applicable to different heterogeneous landscapes :
Goal (A): 'Flux Mapping' - to develop, test, and apply methods based on spatial conditional sampling of EC data to attribute measured GHG fluxes to permanent or changing features in patchy and transient landscapes. This is achieved by a combination of EC measurements, footprint modelling, and remote sensing data. Case studies include methane and carbon dioxide emissions from the Mackenzie Delta, NWT, and GHG emissions from intertidal zones on the Pacific Coast.
Goal (B): 'Flux Attribution' - to develop, test, and apply stable isotope approaches to attribute sources and sinks GHGs in landscapes that are characterized by fluxes from multiple sources and sinks simultaneously. We will use stable isotope techniques to partition carbon dioxide in forests and to verify fuel emission inventories in cities.
Goal (C) 'Flux Upscaling' - to develop, test, and apply new techniques for integrating landscape scale GHG fluxes in areas where source and sink distributions do not allow for simple upscaling local-scale EC measurements due to heterogeneity. We propose to test an open-path laser system approach and boundary layer budgeting to retrieve integrated GHG fluxes at coarser scales over cities and the Mackenzie Delta, NWT.
The program will stimulate the development of new observational and modelling techniques in micrometeorology, relevant for climate change science. It will further fill gaps in our understanding of GHG exchange in Canada's coastal, Arctic and urbanized emission 'hot spots' and identify similarities and differences between these landscapes.