Carbon Dioxide

Human influence on the Earth's atmosphere touched what climate scientists called a dire milestone Friday as concentrations of heat-trapping carbon dioxide nudged up to a level unseen in about 3 million to 5 million years — long before modern humans. A monitoring station in Hawaii recorded carbon dioxide concentrations of 400 parts per million Friday, dramatically up from the 316 parts per million recorded when the station made its first measurements in 1958. The monitor, high atop the Mauna Loa volcano, offers the...

Correction: Correction: An earlier version of this commentary incorrectly represented 12 one-thousandths of 1 percent (0.012 percent) as 0.0012. This version has been updated. Lamar Smith, a Republican, represents Texas's 21st District in the U.S. House and is chairman of the House Committee on Science, Space and Technology. Climate change is an issue that needs to be discussed thoughtfully and objectively. Unfortunately, claims that distort the facts hinder the legitimate...

WASHINGTON — Worldwide levels of the chief greenhouse gas that causes global warming have hit a milestone, reaching an amount never before encountered by humans, federal scientists said Friday. Carbon dioxide was measured at 400 parts per million at the oldest monitoring station which is in Hawaii sets the global benchmark. The last time the worldwide carbon level was probably that high was about 2 million years ago, said Pieter Tans of the National Oceanic and Atmospheric...

LOS ANGELES — Every time Los Angeles exhales, odd-looking gadgets anchored in the mountains above the city trace the invisible puffs of carbon dioxide, methane and other greenhouse gases that waft skyward. Halfway around the globe, similar contraptions atop the Eiffel Tower and elsewhere around Paris keep a pulse on emissions from smokestacks and automobile tailpipes. And there is talk of outfitting Sao Paulo, Brazil, with sensors that sniff the byproducts of burning fossil fuels.

Correction: Correction: An earlier version of this commentary incorrectly represented 12 one-thousandths of 1 percent (0.012 percent) as 0.0012. This version has been updated. Lamar Smith, a Republican, represents Texas's 21st District in the U.S. House and is chairman of the House Committee on Science, Space and Technology. Climate change is an issue that needs to be discussed thoughtfully and objectively. Unfortunately, claims that distort the facts hinder the legitimate...

Maryland has cut its carbon dioxide emissions by 6 percent since 2004, and St. Mary's College of Maryland reduced its by 80 percent this year. Maryland is among the top 10 states cutting carbon dioxide emissions, according to an analysis of government data released Thursday by the state-based, resident-funded Environment Maryland. "It's time to take back control of our energy future. By harnessing the power of the wind and the sun, we can cut pollution and transition to clean energy sources that don't harm the...

WASHINGTON — The old saying that "what goes up must come down" doesn't apply to carbon dioxide pollution in the air, which just hit an unnerving milestone. The chief greenhouse gas was measured Thursday at 400 parts per million in Hawaii, a monitoring site that sets the world's benchmark. It's a symbolic mark that scientists and environmentalists have been anticipating for years. While this week's number has garnered all sorts of attention, it is just a daily...

Elliott Roosevelt Jr., a grandson of President Franklin D. Roosevelt, grins and leans toward visitors in his Dallas office to describe his biggest discovery in 53 years as an oilman. After nursing a single 10-barrel-a-day well in a desolate stretch of west Texas for two decades, Elliott Roosevelt, 76, is embracing a technique he says can liberate a third of the 1.8 billion barrels of petroleum stuck a mile below. He plans to inject carbon dioxide into limestone,...

The shells of some marine snails are dissolving as the seas around Antarctica become more acidic, threatening the food chain, according to a study published in the journal Nature Geoscience. Oceans soak up about a quarter of the carbon dioxide released into the atmosphere each year; as CO 2 levels in the atmosphere increase from the burning of fossil fuels, so do ocean levels, making seas more acidic. This acidification threatens coral reefs, marine...

The Obama administration is leaning toward revising its landmark proposal to regulate greenhouse gas emissions from new power plants , according to several individuals briefed on the matter, a move that would delay tougher restrictions and could anger many environmentalists. The discussions center on the first-ever greenhouse gas regulations for power plants, which were proposed by the Environmental Protection Agency nearly a year ago. Rewriting the proposal would significantly delay any action, and...

WASHINGTON — The old saying that "what goes up must come down" doesn't apply to carbon dioxide pollution in the air, which just hit an unnerving milestone. The chief greenhouse gas was measured Thursday at 400 parts per million in Hawaii, a monitoring site that sets the world's benchmark. It's a symbolic mark that scientists and environmentalists have been anticipating for years. While this week's number has garnered all sorts of attention, it is just a daily reading in the...

Human influence on the Earth's atmosphere touched what climate scientists called a dire milestone Friday as concentrations of heat-trapping carbon dioxide nudged up to a level unseen in about 3 million to 5 million years — long before modern humans. A monitoring station in Hawaii recorded carbon dioxide concentrations of 400 parts per million Friday, dramatically up from the 316 parts per million recorded when the station made its first measurements in 1958. The monitor, high atop the Mauna Loa...

WASHINGTON — Worldwide levels of the chief greenhouse gas that causes global warming have hit a milestone, reaching an amount never before encountered by humans, federal scientists said Friday. Carbon dioxide was measured at 400 parts per million at the oldest monitoring station which is in Hawaii sets the global benchmark. The last time the worldwide carbon level was probably that high was about 2 million years ago, said Pieter Tans of the National...

FOR YEARS, European leaders have flaunted their unwavering commitment to fighting climate change — and chastised the United States for lagging behind. But last week brought yet more confirmation that the continent has become a green-energy basket case. Instead of a model for the world to emulate, Europe has become a model of what not to do. The centerpiece of the European Union's climate plan — indeed, the only major climate policy that acts across all member countries — is a slowly declining...

The Environmental Protection Agency needs more time and will not meet its one-year deadline to impose the first-ever greenhouse gas limits on new power plants. "We are working on the rule and no timetable has been set," EPA spokeswoman Alisha Johnson wrote in an e-mail Friday. She said the agency was still reviewing more than 2 million comments on its proposal. The EPA is likely to alter the rule in some way in an effort to ensure that it can withstand a legal challenge, according to sources familiar...

Elliott Roosevelt Jr., a grandson of President Franklin D. Roosevelt, grins and leans toward visitors in his Dallas office to describe his biggest discovery in 53 years as an oilman. After nursing a single 10-barrel-a-day well in a desolate stretch of west Texas for two decades, Elliott Roosevelt, 76, is embracing a technique he says can liberate a third of the 1.8 billion barrels of petroleum stuck a mile below. He plans to inject carbon dioxide into limestone, potentially...

The Post may have concluded that "fracking" for natural gas can be done safely [" The natural-gas boom ," editorial, Feb. 15], but Marylanders have not. The Post welcomes this controversial method of extracting natural gas, but we have seen neighboring states dive headlong into drilling, only to face regrets later. In Maryland, we are hitting the pause button on fracking and asking important questions first. That's why Gov. Martin O'Malley (D) called for a study of this issue in 2011 and why Sen. Robert A. Zirkin...