In this NASA false-color image, the blue and purple show the hole...

In this NASA false-color image, the blue and purple show the hole in Earth's protective ozone layer over Antarctica on Oct. 5, 2022. Earth’s protective ozone layer is slowly but noticeably healing at a pace that would fully mend the hole over Antarctica in about 43 years, a new United Nations report says. Credit: AP

In the weekly fire hose of news, several items caught my eye.

The first was an assessment from a group of U.N.-backed scientists that good progress is being made to repair Earth's ozone layer, the atmospheric shield that protects us from the sun's harmful ultraviolet light. This is big stuff.

UV-B radiation causes cancer in humans, harms our eyes, damages DNA in animals and plants, reduces the efficiency of photosynthesis, and renders plants less able to store carbon dioxide. Without an effective ozone layer, life could not thrive on Earth.

The scientists said the layer is thickening now and could return to its pre-1980s levels by the 2040s, and by 2066 in Antarctica, where the notorious "hole" in the ozone layer has been appearing each spring. What's especially encouraging is the reason for the change — the Montreal Protocol, a 1987 agreement signed by every nation on Earth that outlawed the production and use of CFCs (chlorofluorocarbons), a class of substances that contain chlorine, which depletes ozone, and that were used in refrigerators, air conditioners, aerosol cans, and foam insulation.

The second item was a story about a project in Montana to recreate part of the vast wild prairie that used to blanket the West, and populate it with the thundering bison that were the linchpin to the rich ecology of those grasslands. It's an effort that began in 2001, and the group known as American Prairie has managed to build what it calls a "habitat base" of 455,840 acres and increase its number of bison — known as a "keystone species" for the benefits they bring to other species — from 16 in 2005 to nearly 800 today.

It's a noble effort, rooted in romance and hard-won science, and has a lot to teach us about the importance of biodiversity and the interconnection of species.

The third item was the latest discoveries pouring back from NASA's James Webb Space Telescope, now in orbit a million or so miles from Earth. The instrument confirmed its first exoplanet — a planet that orbits a star other than the sun — about 41 light-years from Earth, and one that's almost exactly the same size as Earth. It also observed the ongoing formation of stars in a small galaxy close (in space terms) to our Milky Way.

That's in addition to the proliferation of jaw-dropping images that exceed in stun-value the best special effects out of Hollywood. And there's so much more to come. The telescope only lifted off on Christmas 2021 and became operational in July, after discussions about it that began in the 1980s and many missed deadlines and blown budgets.

The common thread in these stories is time — as in, the amount of time it can take to accomplish really good things.

It has been more than 35 years since the Montreal Protocol, more than 20 years since American Prairie began its reclamation effort, and nearly 40 years since the James Webb planning started.

There is a lot to say here about perseverance, of course. But there is also much to say about hope.

Each of these was a daunting task. Repairing the ozone layer, reclaiming the American West, putting a $10 billion telescope in orbit a million miles away. And there still is work to do. But here we are, decades later, with a thicker ozone layer, burgeoning bison herds, and a mushrooming trove of interstellar insight.

Daunting problems are not hopeless problems. They only seem that way if you expect to solve them quickly.

We should be heartened by this, especially when it comes to other environmental problems — like, most notably, climate change. When people work together with purpose and commitment, much is possible.

Columnist Michael Dobie's opinions are his own.