Today’s newsletter takes to the stratosphere to highlight the increasing risk satellites are posing to life back on Earth. You can read and share a full version of this story on Bloomberg.com. For unlimited access to climate and energy news, please subscribe. 

What goes up must come down

By Eric Roston

The “law of conservation of mass” is some high school science that didn’t stick with me. But it’s the key to understanding modern environmental problems, including a new one unfolding in low-Earth orbit.

The law is that the basic stuff of which literally everything is composed — rocks, Pez dispensers, kites, fish, you, me — can’t be destroyed under normal conditions. Atoms and molecules just rearrange themselves into other stuff. 

Many slow-motion environmental disasters are rooted in our collective memory-holing of the law of conservation of mass. When we throw stuff away, it doesn’t stop existing, it just becomes something else.

The classic example is the carbon dioxide in the atmosphere, care of burning hydrocarbons. But there’s a new mass we’re inadvertently conserving that’s growing alarmingly fast: The aluminum, copper, lithium and carbon that goes into rockets, fuel and satellites, and it spells trouble for the ozone layer. 

A SpaceX Falcon 9 rocket with a payload of 20 Starlink satellites over California. Photographer: PATRICK T. FALLON/AFP

There is a satellite boom on. Elon Musk’s SpaceX has launched more than 7,000 satellites to create its Starlink internet constellation, and may keep as many as 42,000 in orbit to reach full coverage. On Monday, Amazon.com Inc.’s Project Kuiper put its first 27 production satellites into orbit, as Executive Chairman Jeff Bezos looks to build an internet constellation to compete against Starlink. 

Industry and regulators have been keen to avoid cluttering low-Earth orbit with so much stuff that things smash into each other. Instead, they engineered new satellites to drop into the atmosphere and burn up at the end of their useful lives of about 5 years. 

And that’s where the conservation of mass comes in. At the rate satellites have historically de-orbited and vaporized, there’s been very little if any threat to the atmosphere. That calculation is changing, though, as the European Space Agency projects 100,000 satellites will be in orbit by 2030, a tenfold increase from today. 

Over the last several years, some scientists have begun to both track how the satellite re-entries are changing the atmosphere and model what might happen if it continues. Ten percent of aerosols in the stratosphere already contain aluminum or other particles originating from incinerated satellites. Black carbon, or soot, generated at high altitudes during launch can end up directly heating the stratosphere and help destroy the ozone layer, the atmospheric band that protects living things from the Sun’s ultraviolet rays. Aluminum oxides formed after satellite re-entry may also be troubling for ozone chemistry. 

Major satellite companies are aware of the growing body of research on the risks associated with reentries, though it’s not yet clear how regulations might evolve in response or how that could impact the industry or the cost of launches.

While the satellites are unlikely to pose as big a risk to the ozone layer as refrigerants and spray cans in the 1980s, they’re “going to become more of a problem,” said Kostas Tsigaridis, a research scientist at Columbia University’s Center for Climate Systems Research. “We should just not close our eyes now because it is small.”

My colleague Sana Pashankar and I talked with satellite industry leaders and the scientists tracking the growing risks, and we’ve got a deep dive into what could be the world’s next environmental problem. We’d love for you to read the full story, and we promise there won’t be a pop quiz after.

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Coming in hot

The big idea

More from Green

US policies around coal power plants and gasoline vehicles moved more in line with the Trump administration’s view this week. 

The US Export-Import Bank is getting back in the business of helping to finance foreign coal power plants, after its board voted unanimously Thursday to lift roughly 12-year-old curbs on its lending.

The decision comes just weeks after President Donald Trump signed an executive order directing Ex-Im, the International Development Finance Corporation and other federal agencies to ensure their policies don’t deter coal mining and power projects.

A coal stockpile at a power plant in Tuticorin, India. Photographer: Prashanth Vishwanathan/Bloomberg

Separately, Republicans moved a step closer Thursday to repealing a federal waiver allowing California to ban gasoline-powered cars by 2035, a policy that had drawn opposition from automakers, fuel producers and Trump himself.

The US House voted 246-164 to roll back an Environmental Protection Agency authorization issued under former President Joe Biden, which let California enact emissions standards even stricter than the US government’s requirements to increase sales of electric and other zero-emission vehicles. Thirty-five Democrats joined with Republicans to vote in favor of the measure.

The Senate now has until mid-May to vote on the California waivers, though that may require overriding a decision by the Senate parliamentarian — the legislative body’s chief rule-keeper — first.

Traffic moves along Interstate 80 in Emeryville, California. Photographer: David Paul Morris/Bloomberg

Trump defends Big Oil as states claim climate harm. The administration sued to block New York and three other states from trying to collect billions of dollars from oil companies for damage caused by climate change.

Investors press HSBC for answers on climate. A group of 30 HSBC Holdings Plc investors is asking the bank to confirm it’s still committed to cutting CO2 emissions, amid concerns Europe’s biggest lender is backing away from its climate pledges.

Climate adaptation is big business. Revenue generated by climate adaptation could hit $4 trillion by 2050 and deliver investment opportunities in sectors from firefighting technology to flood insurance, a new report finds. Meanwhile, venture capital firm Norrsken VC says Europe needs to  double down on investing in climate-friendly startups as Trump has made growth for these companies tricky in the US. 

By Joe Wertz

Northwest Europe started May with a mini-heat wave that set a temperature record in London, while more warm and dry weather is set to dominate the region this month.
After Ireland notched an all-time high for April earlier this week, the UK Met Office said London set a May 1 record of 28C (82F) on Thursday.

There’s a small chance the city could hit 30C, which would be the earliest time in the year that threshold has been reached in records going back to 1860. The UK capital also faces a heightened risk of wildfires, according to the London Fire Brigade.

A woman reads on an unseasonably warm day in London on Wednesday. Photographer: Kin Cheung/AP

Paris could touch 29C Thursday, with Berlin hitting highs of 27C on Friday. The high-pressure system driving the region’s first warm spell of the year is forecast to move out over the weekend, but higher-than-normal temperatures are expected for much of May, according to the Met Office and data from Atmospheric G2.

Temperatures across Europe are increasing due to climate change, according to Met Office meteorologist Aidan McGivern. Last year, the continent experienced its hottest ever year and since the 1980s, the region has warmed twice as fast as the global average.

“I wouldn’t be surprised if it’s the warmest May-April period on record,” McGivern said in a forecast briefing.

Also this week it was revealed the United Arab Emirates had its hottest April in records going back more than two decades, with an average daily maximum temperature of 42.6C (109F).

Read more on Bloomberg.com. 

This week Canadians elected Mark Carney, leader of the Liberal party, to be their prime minister. Carney is a newcomer to politics, but is well known in international finance and climate circles, running both the Bank of Canada and the Bank of England, and founding the Glasgow Financial Alliance for Net Zero (GFANZ). Canada is far from reaching its legally mandated goal to achieve net zero by 2050, and has one of the highest emissions per capita of anywhere in the world. Now Carney has been elected, can he translate his international climate leadership into domestic policy, or will climate fall by the wayside as he fortifies Canada against a trade war with the US?

Bloomberg Green senior reporter and former Toronto Bureau Chief, Danielle Bochove, joins Zero to discuss. Listen now, and subscribe on Apple,  Spotify, or YouTube to get new episodes of Zero every Thursday.

Mark Carney Photographer: David Kawai/Bloomberg

Do you have a compelling story you want to tell? The Bloomberg Green Docs competition is open to all eligible filmmakers who would like to compete to win a $25,000 grand prize for a short climate documentary. The aim is to explore our climate future with documentaries that reveal the world we are making today. Films must be under 10 minutes and submissions will be accepted through May 23. The winner will be announced at the Bloomberg Green Docs Film Festival in Seattle on July 16. Visit the Bloomberg Green Docs official site for more information and rules.

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