Large amounts of methane wafting from tropical wetlands into Earth's atmosphere could trigger warming similar to the "termination" events that ended ice ages — replacing frosty expanses of tundra with tropical savanna, a new study finds. Researchers first detected a strange peak in methane emissions in 2006, but until now, it was unclear where the gas was leaking from and if it constituted a novel trend.

"A termination is a major reorganization of the Earth's climate system," study lead author Euan Nisbet, a professor emeritus of Earth sciences at Royal Holloway, University of London, told Live Science. "These repeated changes have taken the world from ice ages into the sort of interglacial we have now."

"Within the termination, which takes thousands of years, there's this abrupt phase, which only takes a few decades," Nisbet said. "During that abrupt phase, the methane soars up and it's probably driven by tropical wetlands."

When glaciers melt, groundwater springs gush forth through the newly-exposed ground. Even during winter, groundwater springs leak out near the edge of glaciers. When groundwater is exposed to surface temperatures, it rapidly freezes. The resulting ice fields can stretch for kilometers, running several meters thick.

Beneath these glaciers and permafrost, lie colossal deposits of the harmful greenhouse gas, methane. Researchers believe that methane escape might be accelerating warming in this part of the world. To test this theory, Gabrielle Kleber, of the University of Cambridge, in the U.K., and colleagues explored the potential seepage of methane from groundwater springs near melting glaciers.

To collect samples of groundwater, Kleber and colleagues drilled deep into these fields of ice, until they hit the pressurized springs. “We were surprised to find just how much methane was present in these groundwater springs,” Kleber told Advanced Science News. “In fact, sometimes when we’d drill into the ice, we’d find that a lot of very pressurized gas was released before the water. This gas could be ignited, meaning that it was mostly methane.”

The net effect has been a brake on global warming. In this new effort, the research team found evidence that rising atmospheric CO2 has slowed the rate of increase in global photosynthesis because the atmosphere has also grown drier.

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The researchers found that as CO2 levels rose over the last century, global rates of photosynthesis rose along with them accordingly. But starting in the year 2000, things changed. The rise of photosynthesis rates began to slow, and they may stop rising altogether in the near future as the planet grows warmer and drier.

LVNG, a German state-owned railway company, has been devising ways to phase out diesel since 2012. In September 2018, it started running hydrogen fuel-cell trains–the Alstom Coradia iLint trains—on trial routes in the Lower Saxony region.

The commercial rollout of these trains on a railway link, in August 2022, had already been derailed on several occasions. The trains required new hardware and software to be retrofitted for their routes, driver shortages left no spare time to educate them on running hydrogen trains, and there were troubles at the hydrogen refuelling station in winter.

Now a year after the commercial launch, the Lower Saxony state ministry has abandoned ideas for future hydrogen trains, arguing that battery-electric models “are cheaper to operate.”

But researchers are now waking up to another factor, one that could be filed under the category of unintended consequences: disappearing clouds known as ship tracks. Regulations imposed in 2020 by the United Nations’s International Maritime Organization (IMO) have cut ships’ sulfur pollution by more than 80% and improved air quality worldwide. The reduction has also lessened the effect of sulfate particles in seeding and brightening the distinctive low-lying, reflective clouds that follow in the wake of ships and help cool the planet. The 2020 IMO rule “is a big natural experiment,” says Duncan Watson-Parris, an atmospheric physicist at the Scripps Institution of Oceanography. “We’re changing the clouds.”

By dramatically reducing the number of ship tracks, the planet has warmed up faster, several new studies have found. That trend is magnified in the Atlantic, where maritime traffic is particularly dense. In the shipping corridors, the increased light represents a 50% boost to the warming effect of human carbon emissions. It’s as if the world suddenly lost the cooling effect from a fairly large volcanic eruption each year, says Michael Diamond, an atmospheric scientist at Florida State University.

The canal relies on rainwater to move ships through a series of locks that function like water elevators, raising the vessels up and over the continent between the Atlantic and Pacific Oceans.

However, a water shortage due to low rainfall has forced operators to restrict the number of vessels passing through, which is likely to result in a $200 million drop in earnings in 2024 compared to this year, canal administrator Ricaurte Vasquez said Thursday.

The Pacific warming phenomenon known as El Niño, which can cause drought in some nations and flooding in others, is making the situation worse, meteorologists say.

"The big disadvantage that the Panama Canal has as a maritime route, is that we operate with freshwater, while others use seawater," said Vasquez during a presentation to the media.

For years, climate experts have been begging the world's biggest economies to wean themselves off of fossil fuels. Instead, coal use is at an all time high, hitting a brand new record of 8.3 billion metric tons in 2022, up 3.3% from the prior year, according to figures from the International Energy Agency (IEA). The uptick in coal demand has been concurrent with a clean energy boom, as countries across the world turned to non-petroleum based energy sources last year thanks to soaring oil and gas prices. All told, the world produced 10,440 terawatt hours from coal in 2022 - about 36% of the world's electricity generation.

Russia's war in Ukraine, which kicked off an entirely war over energy supply and sanctions in Europe over the course of 2022, sent shockwaves through global energy markets. To shore up energy security, global economies scrambled to find alternative energy supply chains. In the West, this mostly manifested as an intensive growth in the renewable energy sector. In China and India, however, the coal business is booming. The picture is a bit more complex in China, however, where renewables growth has outpaced every other country on earth several times over, but coal still reigns supreme in the global energy mix.

In Buenos Aires, where the average high on Aug. 1 is 58 degrees (14 Celsius), it surpassed 86 (30 Celsius) on Tuesday.

“South America is living one of the extreme events the world has ever seen,” weather historian Maximiliano Herrera tweeted, adding, “This event is rewriting all climatic books.”

The most extreme conditions have occurred in the southern half of the continent, and particularly in the Andes Mountains region.

Temperatures Tuesday rose past 95 degrees (35 Celsius) in numerous locations, including at elevations of about 3,500 to 4,500 feet in the Andes foothills. In some cases, the temperature crested above 100 degrees (38 Celsius) after leaping from morning lows in the 30s and 40s (single-digits Celsius).

For decades to come, under almost all scenarios, climate scientists say we should be prepared to see records shattered so frequently, so routinely, that the statistics and the superlatives — warmest, wettest, lowest, driest — might melt together in the public mind like asphalt in August.

The previously abnormal is becoming our normal.

China’s steel sector has invested around US$100 billion in new coal-based iron and steel capacity since 2021, despite overcapacity, low profitability and China’s commitments to reduce carbon emissions, according to a climate think tank.

Steel firms received approvals from provincial governments to build a massive amount of new coal-based capacity between 2021 and the first half of 2023, including 119.8 million tonnes per annum (Mtpa) of blast furnaces (BFs) and 76.6 Mtpa of basic-oxygen furnaces (BOFs), according to a report released by the Helsinki-based Centre for Research on Energy and Clean Air (CREA) on Tuesday. By the time these plants are fully operational around 2025, their carbon emissions will be roughly equal to the entire emissions of the Netherlands, which emitted over 140 million tonnes of greenhouse gases in 2021, according to CREA.