Abstract
Abstract. High-resolution bottom-up estimation provides a detailed guide for city greenhouse gas mitigation options, offering details that can increase the economic efficiency of emissions reduction options and synergize with other urban policy priorities at the human scale. As a critical constraint to urban atmospheric CO2 inversion studies, bottom-up spatiotemporally explicit emissions data products are also necessary to construct comprehensive urban CO2 emission information systems useful for trend detection and emissions verification. The “Hestia Project” is an effort to provide bottom-up granular fossil fuel (FFCO2) emissions for the urban domain with building/street and hourly space–time resolution. Here, we report on the latest urban area for which a Hestia estimate has been completed – the Los Angeles megacity, encompassing five counties: Los Angeles County, Orange County, Riverside County, San Bernardino County and Ventura County. We provide a complete description of the methods used to build the Hestia FFCO2 emissions data product for the years 2010–2015. We find that the LA Basin emits 48.06 (±5.3) MtC yr−1, dominated by the on-road sector. Because of the uneven spatial distribution of emissions, 10 % of the largest-emitting grid cells account for 93.6 %, 73.4 %, 66.2 %, and 45.3 % of the industrial, commercial, on-road, and residential sector emissions, respectively. Hestia FFCO2 emissions are 10.7 % larger than the inventory estimate generated by the local metropolitan planning agency, a difference that is driven by the industrial and electricity production sectors. The detail of the Hestia-LA FFCO2 emissions data product offers the potential for highly targeted, efficient urban greenhouse gas emissions mitigation policy. The Hestia-LA v2.5 emissions data product can be downloaded from the National Institute of Standards and Technology repository (https://doi.org/10.18434/T4/1502503, Gurney et al., 2019).
Highlights
Driven by the growth of fossil fuel energy demand, the amount of carbon dioxide (CO2), the most important anthropogenic greenhouse gas (GHG) in the Earth’s atmosphere, recently reached an annual average global mean concentration of 402.8 ± 0.1 parts per million, which is on its way to doubling preindustrial levels (IPCC, 2013; Le Quéré et al, 2018)
Hestia fossil fuel CO2 (FFCO2) emissions are 10.7 % larger than the inventory estimate generated by the local metropolitan planning agency, a difference that is driven by the industrial and electricity production sectors
Transportation accounts for the largest share (24.27 ± 2.7 MtC yr−1) of the total, and within the transportation sector, on-road emissions account for the largest portion (20.81 ± 2.3 MtC yr−1)
Summary
Driven by the growth of fossil fuel energy demand, the amount of carbon dioxide (CO2), the most important anthropogenic greenhouse gas (GHG) in the Earth’s atmosphere, recently reached an annual average global mean concentration of 402.8 ± 0.1 parts per million (ppm), which is on its way to doubling preindustrial levels (IPCC, 2013; Le Quéré et al, 2018). We have witnessed the first time that the majority of the world’s inhabitants reside in urban areas. This trend, like atmospheric CO2 levels, is intensifying. Projections show city populations worldwide could increase by 2 to 3 billion this century and triple in area by 2030 (UN DESA 1015; Seto et al, 2012). These two thresholds are linked – almost three-quarters of energy-related, atmospheric CO2 emissions are driven by urban activity (Seto et al, 2014). The pace of urbanization continues to increase and opportunities to avoid carbon “lock-in” – where relationships between technology, infrastructure, and urban form dictate decades of high CO2 development – are diminishing (Güneralp et al, 2017; Seto et al, 2016; Erickson and Lazarus, 2015)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
