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In 2025, the contiguous U.S. experienced its fourth-warmest year on record and 23 billion-dollar weather and climate disasters, totaling $115 billion in damages. Globally, 2025 was the third-warmest year since 1850, with NOAA data indicating it was approximately 1.3°C warmer than the pre-industrial average. The year was marked by record-breaking December heat in the U.S. Southwest and devastating atmospheric river flooding in Washington and Oregon.

The document reports that November 2025 was the third warmest on record globally and the fourth warmest for the contiguous U.S. It highlights a long-term trend of warming winters in the U.S., where the coldest day of the year has warmed by approximately 7°F since 1970. The briefing also notes significant regional anomalies, such as extreme warmth in Texas and heavy rainfall in southern California, while discussing the ongoing La Niña advisory and its expected impacts on weather patterns through early 2026.

The authors report a 71% decline in global shark and ray populations due to overfishing and bycatch, noting that slow reproductive rates hinder recovery. While some U.S. regions like Florida and Hawai’i show signs of recovery, this has led to increased 'depredation'—sharks taking fish from fishers' lines. The authors criticize the SHARKED Act (S. 2314/ H.R. 207) for potentially allowing shark culls as a mitigation strategy and for excluding Indigenous and tribal communities from its task force. They advocate for collaborative, non-lethal strategies, such as reassessing fishing practices and locations, to ensure coexistence between sharks and the fishing industry.

Climate Central's analysis for June to August 2025 reveals that at least 22% of the global population experienced temperatures made at least twice as likely by climate change daily. In the U.S., over 21 million people in 32 cities faced 30 or more 'risky heat' days added by climate change, with some cities, such as Honolulu, seeing all their risky heat days attributed to human-caused warming.

August 2025 was the third warmest August globally on record, with all ten warmest Augusts occurring since 2015. In the United States, 98% of analyzed cities have experienced fall warming, and as of September 9, at least 60% of the country faces abnormally dry or drought conditions. A record-breaking marine heatwave in the North Pacific Ocean, attributed to climate change, is expected to persist into October.

The policy brief argues that while performance incentive mechanisms (PIMs) can drive regulatory outcomes and affordability, they require intentional evaluation to ensure benefits outweigh costs. RMI recommends that PUCs implement recurring and transparent evaluations via web-based dashboards, assess PIMs as a holistic portfolio rather than in silos, create informal stakeholder dialogue spaces to reduce administrative burdens, and utilize existing design guidelines to standardize retrospective evaluations.

The document examines how climate change is creating a home insurance crisis in the U.S., characterized by skyrocketing premiums and widespread policy non-renewals. It asserts that 'Big Oil' companies, who knew about the risks of fossil fuels as early as 1954, are responsible for these conditions. The report highlights specific state-level crises in Florida, California, and Hawaiʻi, and advocates for policy solutions—such as subrogation and legislative surcharges—to shift the financial burden from policyholders to the fossil fuel industry.

Earthjustice reports on its efforts to secure and defend health protections against pollution and toxic chemicals. The organization highlights the use of 'citizen suits' under the Clean Air Act and Clean Water Act to hold polluters accountable, such as litigation against Suncor Energy and the County of Hawai‘i. The report emphasizes a strategic shift toward state and local legal avenues—including constitutional 'right to a healthy environment' claims in Hawai’i and New York—to mitigate the impact of federal rollbacks by the Trump administration. Key achievements include pushing for bans on PFAS in menstrual products in New York, reducing flame retardants in Washington state, and implementing zero-emissions truck rules in California. The document also details the projected life-saving impacts of federal rules secured in 2024, such as the Air Toxics Rule and the Mercury and Air Toxics Rule Update.

The US power sector is experiencing unprecedented load growth, requiring the grid to expand more than five times faster than in the previous two decades. To address this, the report recommends maximizing existing grid value through grid-enhancing technologies (GETs) and demand-side flexibility, accelerating connections via 'energy parks' and streamlined interconnection processes, and adopting proactive, scenario-based planning. It also suggests targeted affordability measures for low-income customers and specialized rate designs for large loads to prevent cost-shifting and stranded-asset risks.

The document outlines the RISE model, where tax-exempt organizations act as solar owners to install systems for LMI households at low or no upfront cost, utilizing the IRS 'direct pay' mechanism to claim the Clean Electricity Investment Tax Credit (ITC). It details an eight-step implementation process: determining project type and team, identifying ownership structures (such as green banks or CDFIs), planning capital stacks, selecting installers, conducting community engagement, constructing projects, claiming tax credits, and managing ongoing operations. The guide emphasizes the importance of trusted community messengers and provides strategies for adapting to potential policy changes regarding federal incentives.

The report argues that rapid declines in battery costs have made near-continuous solar power (24/365 generation) an economic reality in sunny regions. In cities like Las Vegas, achieving 97% reliability for a constant power supply is now cost-competitive at $104/MWh, which is cheaper than new coal and nuclear power. The analysis demonstrates that a relatively small amount of storage—approximately 17 kWh of battery for every 1 kW of stable 24-hour power—is sufficient for most sunny locations. This shift allows solar to support 24/7 clean energy contracts for energy-intensive industries and significantly reduces the need for expensive grid expansions by allowing more capacity to be installed behind existing connections.

A group of state Attorneys General requests that the U.S. Department of Justice recommend legislation to shield energy companies from climate-related liability and restrict federal funding for states pursuing climate lawsuits. The authors argue that such "climate lawfare" undermines national security and economic prosperity by targeting traditional energy resources like oil, natural gas, and coal.

A growing number of US communities and governments are suing fossil fuel companies, arguing they misled the public about climate change. These 'polluter pays' cases seek compensation for climate damages, mirroring the 1990s tobacco litigation. While most cases are in the US, a significant case in Peru involving RWE highlights global implications. The fossil fuel industry is responding with lobbying for legal immunity and efforts to discredit litigants, though some cases, such as Honolulu v. Sunoco LP, are advancing toward trial.

The Danger Season 2025 microsite integrates National Weather Service (NWS) alerts, population data, social disadvantage metrics from the Climate & Economic Justice Screening Tool (CEJST), Climate Central’s Climate Shift Index (CSI), and EPA/AirNow’s Air Quality Index (AQI). The methodology focuses on the period from May to October, identifying counties under extreme weather alerts or experiencing unhealthy air quality. It calculates four daily indicators: the total population facing alerts, the percentage of disadvantaged people affected, the percentage of the population facing at least one alert, and the proportion of extreme heat alerts attributable to climate change. The scope includes the contiguous United States, Alaska, Hawai'i, Puerto Rico, and the U.S. Virgin Islands, though certain datasets like CSI and AQI have specific geographic gaps.

Analysis of NOAA data shows that all 50 U.S. states and 99% of 242 analyzed cities have warmed since 1970. Alaska was the fastest-warming state (+4.3°F), while Reno, Nevada, saw the highest city-level increase (+7.8°F). The contiguous U.S. has warmed by approximately 2.8°F, exceeding the global warming limit of 2.7°F (1.5°C). The document advocates for a clean energy transition through zero-emission vehicles, solar and wind power, and heat pumps to mitigate these trends.

Analysis of 144 U.S. weather stations shows that 88% of cities experienced increased hourly rainfall intensity between 1970 and 2024, with an average increase of 15% across those locations. The highest average regional increases occurred in the Upper Midwest (+18%), Northern Rockies and Plains (+16%), and Ohio Valley (+15%). Individual cities with the largest increases include Wichita, Kansas (+38%), Reno, Nevada (+37%), Fairbanks, Alaska (+37%), and El Paso, Texas (+37%). Projections indicate that with 2°C of global warming, 85% of U.S. counties are likely to see a 10% or higher increase in precipitation on the heaviest 1% of days, with particularly high intensification expected in Alaska (43%) and Hawaii (30%).

Batteries are scaling up rapidly in the US, supporting record solar growth and reducing reliance on gas and coal. In 2024, California and Nevada became the first states to exceed a 30% annual solar share. California's battery capacity grew nearly twentyfold between 2020 and 2024, allowing batteries to become the largest electricity source during evening hours in April 2024. Texas also saw significant growth, installing 3.9 GW of utility-scale battery capacity in 2024. Nationally, the US added 36 GW of new solar capacity in 2024, with 10 GW of utility-scale batteries added, reflecting a trend toward co-located solar-plus-battery projects.

The U.S. clean energy sector saw record solar and battery storage installations in 2024, with renewables accounting for approximately 90% of new capacity. However, progress is hindered by grid interconnection backlogs, rising local opposition, high interest rates, and supply chain shortages. The report also notes a slowdown in EV sales growth and warns that the Trump administration's policies may create further roadblocks to decarbonization.

Analysis of 232 U.S. cities shows that 91% have experienced a long-term decrease in freezing nights since 1970, with an average reduction of 15 nights. This trend is most pronounced in the West, Northeast, and Southwest, and is attributed to climate change driven by the burning of fossil fuels. While fewer freezing nights may reduce acute cold-exposure risks and home heating costs, the trend threatens snow-fed water supplies, winter recreation economies, and fruit crop yields that require winter chill, while potentially expanding the range of disease-carrying pests.

The report examines the technical and institutional challenges of maintaining grid reliability in the United States as fossil fuel plants retire and demand grows from data centers and electrification. It argues that reliability does not require traditional baseload power but can be achieved through a combination of wind, solar, battery storage, and demand-side flexibility. The authors highlight that while 80-90% clean electricity is achievable with current technology, reaching 100% may require 'clean firm' resources like enhanced geothermal or advanced nuclear. Key recommendations include reforming interconnection queues, expanding interregional transmission, and implementing performance-based incentives for utilities to prioritize demand-side solutions.