The layoffs at the agency, the National Oceanic and Atmospheric Administration, started to unfold on Thursday afternoon and numbered more than 800, according to congressional sources. The dismissals are part of a broadening assault on the federal bureaucracy engineered by President Donald Trump and his aide, billionaire Elon Musk, who say they are trying to cut wasteful spending.

"There will be people who die in extreme weather events and related disasters who would not have otherwise," said Daniel Swain, a climate scientist and professor at the University of California, Los Angeles.

In addition to everyday forecasting, NOAA - which houses the National Weather Service, the National Hurricane Center and two tsunami warning centers - provide crucial information to help Americans survive weather emergencies. The cuts come at a time when scientists say climate change is increasing the intensity and frequency of hurricanes, tornadoes, flooding and wildfires.

With faster and more accurate weather warnings, authorities have a better chance of saving lives, experts say. Advances in weather forecasting are credited with bringing down death tolls from weather-related disasters across the world, even as populations have increased and weather has become more extreme.

"Whether they know it or not, every American in every part of the country relies on NOAA every day," Democratic U.S. Senator Patty Murray said in a statement. "This is dangerous and could be catastrophic for our economy."

Musk's so-called Department of Government Efficiency has downsized more than 100,000 of the federal government's 2.3 million workers through a combination of layoffs and buyouts. Trump and Musk say the government is bloated and wasteful.

NOAA, which employs 12,000 people, is part of the U.S. Department of Commerce. The agency's various divisions also develop long-term climate models, conduct environmental research, collect atmospheric data, oversee commercial fisheries and maintain radar systems, among other responsibilities.

While many of its offices are hardly household names, their activities often touch the lives of everyday Americans in tangible ways, such as assuring the safety and supply of seafood and enabling farmers to maximize crop yields.

NOAA data is also used by many countries that cannot afford their own weather monitoring as well as researchers worldwide to advance scientific study.

As at other agencies that have seen terminations, the NOAA staffing cuts were focused on "probationary" workers who had been in their current positions for less than a year and enjoy fewer job protections under the law.

While the National Weather Service was spared, hundreds of scientists working on the models and data that feed weather forecasts were eliminated from their positions.

The layoffs included marine habitat and satellite specialists in the Washington, D.C., region, marine sanctuary analysts in Maine and information technology and human resources staff in Virginia and Rhode Island, according to posts from fired workers on LinkedIn.

Asked for comment, an NOAA spokesperson said, "Per our long-standing practice, we don't discuss personnel matters."

'EVERYTHING'S IN FLUX'

Scientists, terminated workers and Democratic lawmakers reacted with dismay, saying the layoffs would endanger Americans by weakening NOAA's forecasting capabilities and undermining climate research.

Although it is not widely known, most or all private weather companies in the U.S., including forecasts seen on television or phone apps, are "built directly atop backbone of taxpayer-funded instrumentation, data, predictive modeling, and forecasts provided by NOAA," UCLA's Swain said.

Tom Di Liberto, a public affairs specialist and climate scientist at NOAA, was fired on Thursday afternoon. While he was a probationary employee after becoming a full-time worker last year, he had worked for NOAA as a contractor since 2010.

"The private sector can't do what NOAA does, and vice versa," he said. "Clearing out NOAA is like annihilating the first floor of a skyscraper and destroying the building."

The layoffs also included the team at the environmental modeling center, who run NOAA's weather models. A weather station in Alaska has ceased launching weather balloons due to job cuts, Di Liberto said.

A NOAA researcher who studies atmospheric and ocean currents to help forecast hurricanes and generate detailed information for the nation's fisheries said that about 10 young scientists had been abruptly fired on Thursday from his office.

Lindsay Johnson, a climatologist with the National Drought Mitigation Center at the University of Nebraska at Lincoln, said she was concerned the NOAA cuts could impact the group's work monitoring and analyzing drought conditions. The center's weekly drought data is closely followed by farmers, ranchers, commodity traders and agribusinesses.

The group remains funded for the time being, she said.

"The problem is, everything's in flux. You can't really plan for it," she said.

Jane Lubchenco, the former NOAA Administrator under President Barack Obama, said the mass layoffs would not save the government money since NOAA was already a "lean" agency.

"The mass firings today at NOAA are a national disaster and a colossal waste of money," she posted on LinkedIn. "Destroying NOAA's ability to provide life-saving information, keep our ocean healthy, and strengthen the economy makes no sense — no sense at all."