Evaluating a high-resolution urban fossil CO2 emissions inventory using
eddy-covariance flux measurements and source partitioning
Abstract
We present the first quantitative comparison of source-partitioned CO2
flux measurements with a high-resolution urban fossil CO2 emissions
inventory. We use tower-based measurements of CO and 14C to partition
net CO2 flux measurements into fossil and biogenic components in a
suburban environment. A flux footprint model is used to quantify spatial
patterns in fluxes. The partitioned fossil CO2 emissions are compared to
a 200-m resolution emissions inventory (Hestia). The results indicate
that Hestia and the partitioned flux data agree remarkably well on a
seasonal average scale. The Hestia inventory is biased by 3.2% (cold
season) and 9.1% (warm season). Their temporal-spatial patterns match
closely. In addition, biogenic CO2 uptake is 25% of local fossil
emissions during afternoon in the cold season. This work demonstrates
the effectiveness of using eddy-covariance flux measurements both for
evaluating urban emissions inventories and for quantifying urban
ecosystem fluxes.