Towards quantifying urban CO2 emissions for global cities using column CO2 and SIF data
Abstract
Column CO2 (XCO2) and solar-induced florescence (SIF) data retrieved from spaceborne sensors have shed new light on carbon fluxes from global to local scales. Yet, deriving accurate CO2 fluxes from column measurements may be challenging for urban areas which have tremendous potentials for carbon and climate mitigation. Difficulties may include the uncertainties from atmospheric models and the interference from biosphere within and around cities.
Here we attempt to target top-emitting cities around the globe and estimate their CO2 emissions from OCO-2, by leveraging an atmospheric transport model (X-STILT) and a newly developed biospheric model named SMUrF (SIF for Modeling Urban Fluxes). SMUrF is designed to separate out biospheric fluxes from anthropogenic emissions and contains photosynthetical and respiratory information learnt from satellite-based SIF and FLUXNET. Moreover, modeled biospheric fluxes are evaluated against independent flux measurements around a few data-rich U.S. cities and coupled with X-STILT to reveal the urban-rural gradient in biospheric XCO2. We will discuss 1) the error impact on XCO2 from atmospheric transport model, 2) the biospheric interference on interpreting urban-induced XCO2 enhancements, and 3) the dependence of per capita emissions due to population densities by carrying out one of the first observation-based urban scaling analysis. We foresee the approaches presented in this work may offer some new inspirations towards urban emission estimates, which ultimately helps track and evaluate the future trajectories of cities' emissions.- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2019
- Bibcode:
- 2019AGUFM.A53I..01W
- Keywords:
-
- 3322 Land/atmosphere interactions;
- ATMOSPHERIC PROCESSES;
- 0414 Biogeochemical cycles;
- processes;
- and modeling;
- BIOGEOSCIENCES;
- 0428 Carbon cycling;
- BIOGEOSCIENCES;
- 0480 Remote sensing;
- BIOGEOSCIENCES