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New research from Climate Central indicates that climate change accounted for 27% of the rate of heat-related emergency room visits in the U.S. during the warm seasons from 2018 to 2025. The study found that all U.S. regions experienced increased visit rates due to climate change, with the highest rates occurring in southern and western states. A notable peak occurred during the June 2021 northwestern U.S. heat wave, where daily visit rates were approximately 50 times higher than the regional average, with 27% of that rate attributed to climate change.

The report finds that human-induced climate change has reduced rainfall in Jamaica by approximately 6% and in Puerto Rico by about 9%. These changes have increased the likelihood of severe effective precipitation events in both regions compared to a pre-industrial climate. The study highlights that warmer temperatures intensify drought severity through higher evaporation, making the 2026 early wet season rainfall deficits more frequent and severe.

The document presents seven facts regarding the National Park Service (NPS) and its connection to Hispanic/Latino populations. It notes a significant underrepresentation of Latinos in the NPS workforce and leadership compared to their share of the U.S. population. It highlights historical figures like George Meléndez Wright and sites such as Chicano Park and Chaco Culture National Historical Park. The text also expresses concern over the removal of permanent workers since January 2025, the exclusion of U.S. territories from public surveys, and proposed mineral withdrawals in the Greater Chaco region.

Analysis of 243 to 247 major U.S. cities reveals that 95% have seen an increase in unusually warm summer nights since 1970, with an average increase of 24 nights per summer. Using the Climate Shift Index (CSI), the report finds that human-caused climate change now strongly influences an average of 27 warm summer nights per year, compared to just one in the 1970s. The most severe impacts are concentrated in Florida and Puerto Rico, where some cities experience over two months of climate-driven warm nights annually. These trends exacerbate heat stress, disrupt sleep, and increase energy demand for air conditioning, disproportionately affecting vulnerable populations and those in urban heat islands.

In July 2026, the United States experienced widespread above-average temperatures, with an average anomaly of 1.5°F across 192 cities. The Northern Rockies and Plains were the warmest region, exceeding normals by more than 4.0°F. Long-term data indicates that 185 of the 192 analyzed cities have warmed since 1970, with Reno, Nevada, showing the most significant increase. Climate attribution analysis using the Climate Shift Index (CSI) showed that San Juan, Puerto Rico, had 31 days where temperatures were at least two times more likely due to climate change.

Climate change accounted for 27% of the rate of heat-related emergency room visits in the U.S. during 2018-2025. August 2026 was the warmest August on record globally, with record warmth affecting 13.2% of global land and ocean areas. In the U.S., Summer 2026 was the warmest on record for the contiguous region, and August 2026 was the warmest August for average, maximum, and minimum temperatures since 1895. Drought affected at least 81% of the contiguous U.S. as of September 8, 2026, and nearly 8.3 million acres burned year-to-date, driven by increased 'fire weather' days. Attribution analysis using the Climate Shift Index (CSI) indicates human-caused climate change drove summertime warming trends in 91% of analyzed U.S. cities. Additionally, a strong El Niño event is projected to peak around February 2027, with global temperature anomalies potentially reaching 1.7C above pre-industrial levels.

July 2026 was tied for the warmest July on record globally and was the all-time warmest July for the contiguous U.S. This extreme heat, driven by human-caused climate change and a strengthening El Niño, has led to a significant increase in cooling degree days—a proxy for energy demand—across most major U.S. cities. The report also details widespread drought affecting at least 70% of the contiguous U.S. and record-low sea-ice extents in both the Arctic and Antarctic.

Climate Central's analysis of 239 major U.S. cities from 1970 to 2025 found that 95% of these cities experienced an increase in 'mosquito disease days'—days with temperatures suitable for West Nile virus transmission. On average, these cities saw an increase of 18 days per year. The largest increases occurred in the Southeast, Northeast, and Northwest regions, with San Francisco, CA, seeing the highest increase of 52 days. The report also notes that while West Nile virus is the most common mosquito-borne disease in the U.S., warming is expanding the risk and range of other viruses like dengue and Zika, particularly along the Gulf Coast and into the Ohio Valley and Upper Midwest by 2050.

The document distinguishes energy system resilience—the ability to maintain critical services during disasters—from reliability, which concerns day-to-day grid performance. It argues that aging infrastructure, volatile weather, and increasing demand necessitate a shift toward decentralized, renewable energy systems. A primary recommendation is the creation of 'resilience hubs': trusted community spaces powered by clean energy microgrids and energy efficiency measures that provide essential services during crises. The guide suggests scaling these efforts through collaborative funding, updated building codes, the use of electric vehicles as mobile batteries, and partnerships with insurers to incentivize resilient construction.

The document is a formal comment letter opposing the EPA's proposed Legacy/CCRMU Amendments Rule. The signatories argue that the proposal would exempt hundreds of coal ash dumpsites from oversight, weaken monitoring and cleanup requirements, and allow toxic chemicals to exceed federal safe standards, thereby endangering public health and water resources across the United States.

June 2026 was the second-warmest June on record globally, with the Arctic experiencing its warmest June ever. In the U.S., 66% of the contiguous region faced abnormally dry or drought conditions by July 7, 2026, and the West and Southwest regions saw their warmest January-June period on record. A very strong El Niño is forecast to develop between October and December 2026, with an 81% probability, likely pushing global temperatures to or above 1.5C by October. Climate Central's analysis indicates human-caused climate change is a key driver of summertime warming in 91% of analyzed U.S. cities.

In April 2026, the United States experienced an average temperature anomaly of 3.4°F across 192 cities, with the Ohio Valley being the warmest region. The report highlights that 183 of the analyzed cities have shown long-term warming trends since 1970, with Reno, Nevada, seeing the greatest increase. Climate attribution analysis indicates that in San Juan, Puerto Rico, temperatures on 19 days in April were at least two times more likely due to climate change.

In May 2026, the United States experienced slightly below-average temperatures overall, with an average anomaly of -0.2°F across 192 cities. Despite this, the western U.S. saw above-average temperatures, and the Northern Rockies and Plains region was the warmest, averaging more than 1.6°F above normal. Long-term data indicates that 185 of the 192 analyzed cities have warmed since 1970, with Reno, Nevada, showing the greatest increase at 7.5°F. Climate attribution analysis shows that San Juan, Puerto Rico, had the highest number of days (28) where temperatures were at least two times more likely due to climate change (CSI level 2 or higher).

The May 2026 report highlights that the month was the second-warmest on record globally, with carbon dioxide levels reaching a new monthly peak of 432.3 ppm. In the United States, spring 2026 was the second-warmest on record for the contiguous U.S., while 77% of the region experienced abnormally dry or drought conditions as of early June. The report also notes a developing potentially very strong El Niño and record-low snowpack in several western states.

The report highlights that the Maryland State Retirement and Pension System (SRPS) has a high allocation to private markets, which obscures significant climate risks due to the opacity of these investments. It identifies specific exposure to fossil fuel assets through managers like BlackRock's Global Infrastructure Partners (GIP) V and recommends the adoption of science-based climate targets and increased disclosure to mitigate financial risk.

In Q4 2025, U.S. clean energy investments were characterized by significant uncertainty driven by a record 43-day government shutdown, the One Big Beautiful Bill Act (OBBBA), and Department of Energy (DOE) funding cuts. While utility-scale solar and storage remained strong, with $18 billion in actual investments, other sectors like wind, hydrogen, and sustainable aviation fuel (SAF) faced substantial project cancellations. Nuclear energy showed signs of growth through large-scale partnerships and DOE loans, while the manufacturing sector saw $8.4 billion in EV supply chain cancellations, partly due to shifting federal incentives and corporate pivots toward gas and hybrid vehicles.

April 2026 was the fourth-warmest month globally on record, with the contiguous U.S. experiencing its third-warmest April. The report highlights severe drought in the Southeast U.S., record-low Western snowpack, and a persistent marine heat wave off the coasts of California and Mexico. Using the Climate Shift Index (CSI), the analysis attributes springtime warming trends in 98% of analyzed U.S. cities to human-caused climate change, with exceptional warmth noted in Honolulu and San Juan. Forecasts indicate a high probability of a strong El Niño developing later in 2026, potentially driving global temperature anomalies above 1.8°C relative to pre-industrial levels by early 2027.

Between December 2025 and February 2026, human-caused climate change significantly influenced global temperatures, with more than one in six people daily experiencing temperatures at least twice as likely due to climate change. In the United States, a sharp divide occurred: western states saw record-breaking warmth, with nine states experiencing their warmest December-February on record and Casper, Wyoming, recording the highest temperature anomaly globally among 960 analyzed cities. Conversely, the eastern U.S. faced below-average temperatures and cold snaps that the Climate Shift Index (CSI) indicates were made less likely by climate change. The record warmth in the west has led to low snowpack in Oregon, Colorado, and Utah, threatening water supplies and increasing wildfire risks.

March 2026 was the warmest March on record for the contiguous U.S., characterized by a historic snow drought in the West and extreme heat that increased cooling energy demand. Globally, the month was the second-warmest on record, with Arctic sea-ice reaching a near-record low maximum. In the U.S., severe drought affected 77% of the contiguous region, while Hawaii experienced record-breaking precipitation due to Kona lows.

The Union of Concerned Scientists reports that the Trump administration has granted Clean Air Act exemptions to over one-third of 546 eligible industrial facilities, including coal plants and chemical manufacturers. This policy affects nearly 4.6 million people and over 4,300 schools and daycares, with a disproportionate impact on communities already facing high environmental and social stressors. The administration utilized a national emergency provision in March 2025 to allow a two-year exemption, which the EPA intends to make permanent.