Greta Thunberg sees failure at climate change summit. She's wrong.

Only a few days into the United Nations' two-week climate conference, activist Greta Thunberg pronounced it a failure. The Swedish teen famous for scolding polluters later went on to slam the "very vague" agreement struck as the COP26 summit wrapped up in Glasgow last week, saying it succeeded only in "watering down the blah, blah, blah."

She wasn't alone in her disappointment. Even Alok Sharma, the British politician presiding over the conference, fought back tears as he declared himself "deeply sorry" about last-minute wording in the final agreement to "phase down" rather than "phase out" the use of coal for heat and power.

Time for a reality check. It should come as no surprise that COP26 ended without a revolution. There was no way to put an immediate end to the planet's current reliance on fossil fuels, as Thunberg evidently expected. Success, in this case, depends on your expectations, and ours were mostly exceeded.

First, the conference ended with an agreement. That was no foregone conclusion going in, especially when China's Xi Jinping and Russia's Vladimir Putin decided not to show, and President Joe Biden had fences to mend after four years of climate hostility from former President Donald Trump.

While the final agreement is carefully hedged, it calls for more urgent emission cuts and promises assistance for developing countries adapting to climate impacts. Sharma's tears notwithstanding, this was the first international climate deal to explicitly call for reducing the use of coal, which is the worst fossil fuel for greenhouse-gas emissions.

The landmark 2015 Paris Agreement didn't even mention the role of fossil fuels in climate change. Today, we have a deal corresponding to the facts that scientists have known for many years: When carbon dioxide, methane and similar gases blanket the planet, they trap heat like a greenhouse. The result is global warming, which in turn causes severe weather and dangerously high sea levels.

The largest source of emissions comes from burning coal, gas and oil for electricity, heat and transportation. Agriculture and forestry contribute emissions on a vast scale as well. That's the problem the world needs to solve — and calling out coal was a significant step forward.

It took six years to work out the details after the Paris Agreement established an initial framework for this potentially game-changing marketplace. Chicagoans with roots in commodity trading can rightly wonder what took so long.

Part of the complication resulted from experiments in the past, when carbon credits were traded without internationally recognized rules. COP26 negotiators agreed on a formula for valuing and tracking the old credits and addressed a loophole that could have allowed some countries to double-count their credits.

Getting the rules straight is essential, in part to keep rich nations from snapping up discounted credits so they can keep emitting as usual. Though operational details still need to be worked out, we have high hopes that a functioning market will encourage new investment and reduce emissions overall.

Finally, the COP26 agreement directs the world's governments to arrive at COP27 in Egypt next year with updated plans for cutting emissions by 2030 and additional details on how to assist developing countries adapting to climate change. By putting participating nations on the hook to update their goals and report on their actions more regularly than in the past, the agreement shows a greater sense of urgency that even Thunberg should appreciate.

In the meantime, what can individuals do to make a difference? Quite a lot, actually.

Speak up about your concerns but do yourself and those around you a favor by staying out of the "green shame" game — as in "flight-shaming" those who travel by air, "meat-shaming" those who don't eat vegan and "fashion-shaming" those wearing cheap, high-volume clothes.