The University of Maryland steps up to develop a U.S. Greenhouse Gas Inventory and Analysis

• The U.S. is in the process of withdrawing from international climate commitments, and the EPA failed to release its annual greenhouse gas inventory report two years in a row.
• The University of Maryland Center for Global Sustainability moved ahead and developed a foundational report based on the same methods and data the EPA previously used to develop its greenhouse gas inventory report.
• This report provides stakeholders with critical information to combat climate change and protect public health while demonstrating collaboration and transparency.

Taxes aren’t the only thing due today– April 15^th is also the deadline for signatories of the United Nations Framework Convention on Climate Change (UNFCCC) to submit their national greenhouse gas (GHG) inventory reports, which estimate annual GHG emissions by country.

The UNFCCC treaty was signed by all United Nations member states, but in February 2026 the United States announced it was withdrawing from it effective February 2027. This comes on the heels of the U.S. failing to submit a GHG inventory in April 2025, joining Russia as the only Annex 1 country to not meet their treaty obligations. The U.S. Environmental Protection Agency (EPA) has developed GHG inventory reports since 1997 and has shown leadership by consistently exceeding the minimum requirements for detail and transparency and providing invaluable data and methods to other countries and academics developing their own inventories.

In response to this failure by the EPA, EDF submitted a Freedom of Information Act request and obtained the (already completed) 2025 GHG inventory, which we posted on our website. To date, the EPA appears to have not even begun working on the 2026 GHG inventory.

The University of Maryland Steps Up

The University of Maryland Center for Global Sustainability (CGS) recently  created a foundational report called Greenhouse Gas Inventory and Analysis for the United States (GHGIA) using the data and methods underlying earlier inventories. The report from University of Maryland (UMD) estimates the country’s annual GHG emissions by sector from 1990 to 2024. It’s a watershed moment of U.S. universities and scientists continuing to build on critical scientific work that helps policymakers and stakeholders address climate and protect public health.

The main findings of the report are that total GHG emissions in 2024 were roughly 5,300 million metric tons of CO₂ equivalents, a 3.8 percent decrease from 1990 and a 0.2 percent annual increase from 2023. UMD plans to update the GHGIA and use future reports as opportunities to innovate and improve on methods as new data and scientific techniques become available to more accurately estimate emissions. UMD should be applauded for completing the difficult task of providing the public with a rigorous, data-driven GHG inventory that helps us understand where emissions are coming from.

The GHG inventory is not a political issue – it is a science-based collection of data on the state of GHG emissions within the United States. Around the world, people and communities continue to act on this exact kind of scientific evidence, working to implement non-partisan solutions such as transitioning to renewable energy and eliminating methane emissions from the oil and gas industry. The UMD GHGIA report is scientifically robust and can be used by global stakeholders for many purposes, including informing their climate models. Critical scientific information such as the GHG inventory should be publicly available and shared with all who can use it. We are grateful that groups like UMD are stepping up to keep the world as informed as possible about greenhouse gas emissions and climate change.