Governments have a wide range of tools to reduce greenhouse gas emissions and prepare for a warming planet, from pricing carbon and funding clean energy to updating building codes and paying farmers to change how they work the land. Some of these policies target the biggest sources of pollution directly, while others reshape markets so that cleaner choices become the default. Here’s how the major levers work in practice.
Putting a Price on Carbon
The most direct economic tool is making pollution expensive. Governments do this in two main ways: carbon taxes and cap-and-trade systems. A carbon tax sets a fixed price per ton of emissions, giving businesses a predictable cost they can plan around. Cap-and-trade systems work differently. The government sets an overall emissions limit, issues a fixed number of pollution permits, and lets companies buy and sell them. As the cap tightens over time, permits become scarcer and more expensive, pushing companies toward cleaner operations.
Both approaches create a financial incentive to cut emissions, but they differ in what they guarantee. A carbon tax guarantees the price of pollution but not how much total pollution drops. A cap-and-trade system guarantees total emissions stay below the cap but lets the price fluctuate. The European Union runs the world’s largest cap-and-trade market. Canada and several other countries use a national carbon tax. In the U.S., California operates its own cap-and-trade program, though no federal carbon price exists.
Investing in Clean Energy Technology
Government funding accelerates technologies that aren’t yet cheap enough to compete on their own. One prominent example is direct air capture, a technology that pulls carbon dioxide straight out of the atmosphere. The U.S. Department of Energy has committed $3.5 billion to develop four regional direct air capture hubs across the country, with an additional $1.8 billion announced in late 2024. These facilities aim to remove meaningful quantities of CO2 that other strategies can’t address, like emissions from aviation or heavy industry.
Beyond carbon removal, governments fund research into battery storage, advanced nuclear reactors, green hydrogen, and next-generation solar panels. Tax credits for renewable energy installation have driven dramatic cost reductions over the past decade. When governments absorb the financial risk of early-stage technology, private investors follow once the technology proves viable.
Updating Building Standards
Buildings account for a substantial share of energy use, mostly through heating, cooling, and hot water. Governments can require new construction to meet stricter energy efficiency standards, which locks in lower emissions for decades since buildings last a long time. In 2024, the U.S. Department of Housing and Urban Development finalized a rule adopting updated energy efficiency standards for all new federally financed housing, covering both single-family homes and multifamily buildings.
The compliance timeline varies by program. New single-family homes financed through FHA or USDA loans must meet the standards within 18 months, while multifamily projects have 12 months. Rural areas with higher poverty rates get an extended 24-month window. The updated codes also include optional electrification-ready provisions, meaning new homes can be built so that switching from gas furnaces to electric heat pumps later requires minimal retrofit work. Several states and cities have gone further, banning natural gas hookups in new construction entirely.
Reforming Agriculture
Farming is both a source of emissions and a potential carbon sink. Governments can pay farmers to adopt practices that store carbon in soil and reduce pollution. The USDA’s Partnerships for Climate-Smart Commodities program has reached more than 60,000 farms covering over 25 million acres. Participating farmers use techniques like cover cropping, no-till planting, and improved nutrient management. Across the life of the funded projects, the program is expected to sequester more than 60 million metric tons of carbon dioxide equivalent.
These programs work on a voluntary, incentive-based model. Farmers receive financial and technical assistance through partner organizations, which helps offset the upfront cost of changing long-established practices. The approach also creates market demand for “climate-smart” labeled commodities, giving producers a potential price premium that outlasts the government funding itself.
Restoring Forests at Scale
Trees absorb carbon dioxide as they grow, making reforestation one of the simplest and most cost-effective climate strategies available. In the U.S., roughly 4 million acres of national forest land need replanting, much of it due to wildfires in recent years. The REPLANT Act, signed into law as part of the 2021 Infrastructure Investment and Jobs Act, removed the funding cap on the federal Reforestation Trust Fund, significantly expanding the resources available for planting trees on public lands.
Reforestation isn’t just about carbon. Restored forests reduce erosion, protect watersheds, and improve habitat. The challenge is pace: planting millions of acres requires nursery capacity, seed supply, and labor that take years to scale up. Government programs set the targets and provide the money, but the physical work of growing and planting seedlings creates a bottleneck that policy alone can’t solve overnight.
Financing Climate Action Abroad
Climate change is global, and many of the countries most vulnerable to its effects have the fewest resources to respond. Wealthy nations fund adaptation and emissions reduction in developing countries through mechanisms like the Green Climate Fund. In 2025, the fund channeled a record $3.26 billion to developing countries, surpassing its previous high of $2.9 billion set in 2021. A single board meeting in 2025 approved $1.332 billion across 22 new projects, the largest single-meeting total in the fund’s history.
The funded projects target the countries with the greatest need: least developed countries, small island developing states, and African nations. The money supports renewable energy installation, reforestation, land-use improvements, and energy efficiency upgrades. It also funds adaptation projects that help communities prepare for floods, droughts, and rising seas that are already unavoidable regardless of future emissions cuts.
Transportation and Infrastructure
Transportation is the largest source of greenhouse gas emissions in the U.S. Governments shape this sector through fuel efficiency standards for vehicles, incentives for electric vehicle purchases, and investment in public transit. Setting increasingly strict tailpipe emission limits pushes automakers to sell more electric and hybrid models. Purchase rebates and tax credits lower the sticker price for buyers, accelerating adoption.
On the infrastructure side, expanding rail networks, bus rapid transit, and protected bike lanes gives people alternatives to driving. High-speed rail projects, while expensive and slow to build, can replace short-haul flights on busy corridors with a far lower-emission option. Freight is harder to decarbonize, but governments can fund electrification of port equipment, incentivize zero-emission trucks, and invest in rail freight capacity to move goods off highways.
Regulation and Standards
Sometimes the most effective tool is simply setting a rule. Governments can mandate that a certain percentage of electricity come from renewable sources by a target year. They can ban the sale of new gasoline-powered cars after a specific date. They can require large companies to disclose their emissions publicly, which creates pressure from investors and consumers even without direct regulation.
Methane rules offer a clear example. Methane is a potent greenhouse gas, and much of it leaks from oil and gas infrastructure. Regulations requiring companies to find and fix leaks deliver large climate benefits at relatively low cost, since the captured gas has market value. These standards don’t require new technology or massive investment. They require enforcement.
The most effective government climate strategies combine several of these tools. Carbon pricing creates a broad economic signal. Targeted investments fill gaps where the market moves too slowly. Regulations set floors that prevent backsliding. And international finance ensures that progress in wealthy countries isn’t offset by rising emissions elsewhere. No single policy is sufficient on its own, but together they form a toolkit that can reshape energy systems, land use, and economic incentives at the scale the problem demands.