Emissions

An important part of establishing and reaching climate goals is understanding the past and current state of GHG emissions in our community. While the County has a long record of GHG emissions data, this Climate Action Strategy is oriented around the 2019 Community-Scale GHG emissions inventory. The data from this inventory serve as a snapshot in time, characterizing our entire community’s emissions in calendar year 2019 and establishing a baseline for the GHG emissions targets presented in this strategy. Progress towards the targets and actions identified here will be measured against this baseline.

The 2019 Community-Scale GHG emissions inventory indicates that energy use in buildings and fuel use from transportation activities continue to be the two biggest sources of GHG emissions in Miami-Dade at 41% and 55% of all GHG emissions, respectively. While emissions related to water use and waste generation are a relatively small proportion of the County’s emissions profile, these sectors are a critical source of methane (CH₄), a greenhouse gas with one of the highest global warming potential values. The total Community-Scale GHG emissions for 2019 was 36.5 million metric tons of carbon dioxide equivalent (MMT CO₂e).

Taking the 2019 Community-Scale inventory into our broader historical context, GHG emissions have increased 43% between 2008 and 2019, from 25.5 to 36.5 MMT CO₂e, respectively (Figure 4). These changes have largely been driven by increases in emissions from the transportation sector as both population and economic activity have continued to grow. However, interpreting the reasons behind the changes in emissions data over time can be difficult due to changes in inventory scope and methodology. For example, a change in inventory methodology between 2010 and 2015 resulted in a more holistic accounting for transportation emissions, which appears in the emissions data as a large increase between inventory years. Finally, while the net trend for Community-Scale emissions has been an overall increase since 2008, per capita emissions have held relatively constant since 2013, indicating that the amount of greenhouse gas emissions generated per resident is largely staying the same.

Meeting the ambitious emissions reductions goals laid out in this strategy requires a comprehensive understanding of the emissions reduction potentials of various activities such as reducing the number of people driving cars or reducing electricity use in buildings in Miami-Dade County.

To estimate the impact of emissions reduction activities, the County first creates a baseline forecast which projects a “business-as-usual" scenario in which demographic and economic changes are the drivers of changes in emissions. This scenario does not include any implementation of the approaches proposed here in the Climate Action Strategy. These basic growth assumptions result in a baseline scenario in which emissions steadily increase over time as population and economic activity continue to grow. Other key inputs to the baseline forecast scenario are known future changes in the emissions generated by the electricity grid and known future changes in vehicle fuel efficiency.

From this baseline, the suite of emissions-reducing targets outlined in this strategy are applied to the forecast to generate a scenario that represents the impact of fully implementing the Climate Action Strategy.  Each emissions reduction approach varies in the sectors it targets (for example – renewables address energy use in buildings) as well as their intensity and duration. This collection of emissions reduction targets together represents the County’s planned emissions trajectory through 2030 and, ultimately, 2050. However, all emissions trajectories beyond 2050 are represented as a dashed line due to challenges and uncertainty in data availability and quality for future emissions factors and growth rates past 2030. For example, changes to national climate or clean energy standards could result in significant changes to Miami-Dade's emissions forecast.

A key conclusion from the forecast scenarios presented here is that fully implementing the Climate Action Strategy is integral to putting the County on a pathway to net-zero emissions. In addition, the County’s planned emissions reduction approaches do not currently meet the interim 2030 emissions reduction target. The current suite of proposed approaches will decrease emissions by 33%, or 11.9 MMT CO₂e, by 2030 from our 2019 baseline. The remaining GHG emissions “gap” represents a critical opportunity where additional bold actions by County government, continued input from our community, new technologies, and improvements in environmental standards and regulations at the state and federal level can help Miami-Dade's fully realize it’s climate goals.

Looking beyond the release of Climate Action Strategy, Miami-Dade is committed to continuing to produce and update its GHG emissions inventories on a regular basis. This includes close collaboration with our municipalities and regional partners to continue to improve the alignment of GHG emissions methodologies and data to provide a clear picture of South Florida’s climate work. The County will build on the target-based forecasting scenarios presented here by monitoring the real-world implementation of the Climate Action Strategy and reporting on future emissions reductions and progress towards climate goals. This approach will be critical given the impact that actions beyond the County’s control have on our GHG emissions trajectory. As an example, many of the actions proposed here by Miami-Dade County follow broader national trends towards an increased reliance on electricity as a power source. This is best captured by the growing adoption of electric vehicles, which shifts the source of emissions from “tailpipe” fossil fuel combustion to the electricity grid.

Critically, then, our ability to reduce emissions will be increasingly tied to decisions by State regulators and utilities regarding the fuel sources used to power the electricity grid. Changes to utility practices, as well as additional environmental regulations related to buildings, transportation, and waste, are driven by state and federal government policy decisions. Miami-Dade will continue to update both our emissions inventories and forecasts to reflect the latest developments in standards, best practices, or regulations related to the utility electricity grid, vehicles, and buildings.

The Climate Action Strategy aims to cut communitywide emissions 50% by 2030. Even if all targets in each of the seven approaches is achieved, an emissions gap will remain. The primary sources of that gap are emissions from the electric grid and fuel for vehicles, especially airplanes. Closing the gap will take transformative collaboration with state and federal governments and the private sector. No one industry or government has all of the solutions today. We must discover and create them together.

Based on current plans, carbon free electricity from the grid will increase from 28% in 2022 to 38% in 2030, when over 61% will still be produced by methane intensive natural gas. Reducing emissions from the grid will only be achieved through partnerships with utilities that deliver electricity and gas to our community. Miami-Dade County stands ready to pursue any opportunity to cut emissions by developing renewable, clean sources of energy including established technology like solar and emerging solutions like green hydrogen and battery storage.

As the owner of a major international airport and seaport, Miami-Dade County is excited to accelerate the decarbonization of air and sea travel. We hope to be the testing ground for launching new carbon free transportation solutions with airlines, cruise lines, and the shipping industry. The door is open for collaboration and innovation.

Meeting this moment will take the combined brilliance of our universities, entrepreneurs, utilities, financial institutions, government employees, and residents. Together the gap can be closed by building a smart electric grid powered by clean energy that is paired with massive investments in building efficiency and electrification of transportation.

Miami-Dade Electricity Grid Sources 2022-2030

Source: Florida Power and Light 10-Year Site Plan 2021

The County’s ability to measure its emissions, take effective action, and monitor progress towards emissions goals depends on maintaining a robust emissions data set and inventory methodology. Miami-Dade County practices credible GHG accounting as required by the Global Protocol for Community-Scale Greenhouse Gas Inventories (GPC). Following these standards ensures that Miami-Dade County’s emissions inventories are robust from the beginning and allow the County to stand peer-to-peer with communities and municipalities utilizing the GPC standard in Florida and across the world. With over three decades of inventory experience, the County has refined its methods over time to ensure inventories are thorough and include all critical emissions sources.

The County conducts two types of greenhouse gas emissions inventories: Community-Scale Inventories and Government-Scale Inventories. The Community-Scale Inventory includes all emissions activity occurring within the geographic boundaries of Miami-Dade County. This scale is useful to assess the effectiveness of community- or county-wide programs targeting a variety of sectors. In contrast, the Government-Scale Inventory is focused on understanding emissions related to County government operations. Some examples of included activities are County building and fleet operations. This supplement to the Community Inventory helps the County government act as an emissions reduction leader and identify the effectiveness of policies which target emissions specific to government operations. All emissions data presented in this document are derived from the 2019 Community-Scale Inventory.

Miami-Dade County conducts its GHG emissions inventories using ClearPath, a cloud-based emissions management tool developed by the International Council for Local Environmental Initiatives (ICLEI). ClearPath is designed around the Local Government Operations Protocol and US Community Protocol and supports reporting under the GPC standard to facilitate credible emissions accounting and reporting. In addition, the County uses ClearPath to forecast future emissions scenarios, set mitigation goals, create targeted climate action plans, and track progress over time. In this Climate Action Strategy, Miami-Dade County reports GHG emissions totals in CO₂ equivalent, or CO₂e, a metric standard of emissions measurement that is used to aggregate emissions from a variety of greenhouse gases (GHG) such as NO₂, CH₄, and CO₂ on the basis of their common global-warming potential. Miami-Dade County reports emissions in CO₂e to enable standardized understanding of impacts of all greenhouse gases accounted for in the inventory process. Once complete, Miami-Dade County’s greenhouse gas emissions inventories undergo third-party verification by technical advisors at ICLEI. ICLEI staff assist Miami-Dade in conducting quality assurance and quality control reviews of inventories before they are marked as verified and complete. This additional level of verification adds independent rigor to the County’s emissions accounting.

Finally, a key part of this process is the establishment of emissions reduction targets. Generally, Miami-Dade's GHG emissions reduction progress has historically been measured against the County’s emissions levels in 2008, the baseline established by the Board of County Commissioners through the County’s Comprehensive Master Development Plan (CDMP) (Figure 9). Building on these goals and in line with the County’s participation in the Race to Zero program and other commitments, this Climate Action Strategy reframes our targets to focus on a more ambitious 50% reduction of GHG emissions by 2030 from a 2019 baseline level, with an overall goal to reach net-zero emissions by mid-century (2050).