Climate and environment updates: Heat wave hot spots identified across the globe

Maine has become the latest in a growing number of states to sue the fossil fuel industry over the impacts of global warming.

Maine Attorney General Aaron Frey accused major fossil fuel companies of deceiving Mainers for decades about the impact their product has on human-amplified climate change.

"For over half a century, these companies chose to fuel profits instead of following their science to prevent what are now likely irreversible, catastrophic climate effects," Frey said in a statement.

The lawsuit, filed in state court on Tuesday, alleges the defendants knew as early as the 1960s that an increasing use of fossil fuels could potentially bring devastating consequences to Maine. The state argues the companies not only failed to warn residents about the consequences, but knowingly concealed their knowledge about the long-term negative impacts that Maine's people, environment and economy could face.

The filing states the companies focused on creating public doubt by launching public relations campaigns targeting the science of climate change and the impacts of burning fossil fuels. It is seeking financial compensation for both past and future climate-related damages and for the companies to cease their ongoing deception in Maine.

"They burdened the state and our citizens with the consequences of their greed and deception," Frey said.

Maine Gov. Janet Mills applauded the attorney general's actions, saying in a statement that "for decades, big oil companies have made record profits, taking billions out of the pockets of Maine people while deliberately deceiving them about the harmful impacts of fossil fuels -- impacts that Maine people see and feel every day."

Maine joins a growing list of more than 20 states -- including California, Minnesota, Massachusetts and Vermont -- that have brought similar types of lawsuits to date. Earlier this year, Vermont's Climate Superfund Act became law, seeking financial accountability for climate change-related damages brought by fossil fuel companies. However, due to stipulations in the law and likely lawsuits, it's expected to be several years before any potential first charge to fossil fuel companies would be attempted.

-ABC News meteorologist Dan Peck

Widespread drought conditions are still a significant concern across the country, with parts of the Northeast, northern Plains and Southwest currently experiencing some of the worst impacts, according to a U.S. Drought Monitor update released Wednesday.

Overall, more than 40% of the contiguous United States remains in a drought. This is an improvement, however, from the beginning of the month when more than half of the lower 48 faced drought conditions. Recent heavy rain along the West Coast and parts of the Midwest brought significant drought relief to portions of Washington, Oregon, Wisconsin and Illinois.

As a result, drought coverage decreased from 45.48% to 41.45% versus last week. While some regions experienced a notable improvement, the recent soaking in the Northeast was only enough to pause the fire danger and trend of intensifying drought conditions -- for now.

The current drought situation in the Northeast took months to evolve, and it will take several more rounds of significant rainfall over the span of weeks or even months to completely eliminate the widespread drought in the region.

After a few rounds of beneficial rain, the National Oceanic and Atmospheric Administration's Climate Prediction Center says a large part of the country will likely experience below-average precipitation in early December, particularly in the West, Plains and East Coast.

Much of the western Gulf Coast and northern Plains could see above-average rainfall during this period. Drought relief across the country will, at the very least, take a pause through the beginning of next month.

-ABC News meteorologist Dan Peck

A major water supplier in the West is once again in the spotlight for its unpredictable future.

The Colorado River, the water source for 40 million people across the west, is in a worse state than previously believed, according to a recent study published in Earth's Future.

Drought and dry conditions, compounded by climate change, put the Colorado River in greater jeopardy, the study's authors said.

"It doesn’t take a lot of climate change to put the system into a very vulnerable future," said Dr. Patrick Reed, a civil and environmental engineer at Cornell University and co-author of the study.

Colorado's West Slope River Basins "are essential water sources for the Colorado River and play a vital role in supporting the state of Colorado's local economy and natural environment," according to the study. The West Slope River Basins contribute nearly 70% of the streamflow deliveries to Lake Powell, the nation's second-largest reservoir.

But drought has significantly depleted Lake Powell’s water supply, leading to the first-ever water shortage in the Upper Colorado River Basin in 2021 and more dependence on the West Slope Basin supply.

"The Colorado River is extremely stressed and overallocated," Reed said.

The Colorado River supplies water to seven states and Northern Mexico. Agreements about how the water is divided are up for renegotiation in 2026.

-ABC News' Charlotte Slovin

U.S. fuel economy reached a record high in 2023 at the same time that greenhouse emissions reached a record low, according to the U.S. Environmental Protection Agency's annual Automotive Trends Report released Monday.

The report also states that model year 2023 electric vehicles and plug-in hybrid vehicles have reduced carbon dioxide emissions by 11%.

"This report provides a critical data-driven affirmation that strong, technology-neutral standards can underpin environmental progress while saving drivers money at the pump," EPA Administrator Michael Regan said in a statement.

New vehicle CO2 emissions are now at a record low of 319 grams per mile, which reduces the impact on climate change. Battery and plug-in hybrid vehicles, combined with fuel cell vehicles, are expected to reach 14.8% of overall vehicle production in 2024, a trend that is expected to grow across the industry, according to the report.

Passenger cars and light trucks accounted for 17% of total U.S. greenhouse gas emissions in 2022, underscoring the need for further reductions across the industry, experts said.

-- ABC News Climate Unit's Dan Manzo