There are two numbers that the climate science and climate crisis communities use as the primary indicators of the climate future. The first is the 2 degrees C discussed in a prior post, the maximum temperature rise it's thought we can cope with, which is almost certain to be exceeded, probably by mid-century. Even a degree higher could well have catastrophic effects affecting everyone.
The other number is the amount of carbon dioxide in the atmosphere, measured as parts per million, or ppm. As this AP story puts it, "Years ago, it passed the 350 ppm mark that many scientists say is the highest safe level for carbon dioxide. It now stands globally at 395." The goal of many climate activists is to get below that 350 ppm mark to limit future damage. But the latest evidence is that the number is still rising, and faster than ever, according to scientists studying atmosphere in the Arctic at labs like the one pictured here. This same story:
"The world's air has reached what scientists call a troubling new milestone for carbon dioxide, the main global warming pollutant. Monitoring stations across the Arctic this spring are measuring more than 400 parts per million of the heat-trapping gas in the atmosphere...So far, only the Arctic has reached that 400 level, but the rest of the world will follow soon."
Globally, the average carbon dioxide level is about 395 parts per million but will pass the 400 mark within a few years, scientists said. The Arctic is the leading indicator in global warming, both in carbon dioxide in the air and effects, said Pieter Tans, a senior NOAA scientist."This is the first time the entire Arctic is that high," he said.Tans called reaching the 400 number "depressing," and Butler said it was "a troubling milestone."
"It's been at least 800,000 years — probably more — since Earth saw carbon dioxide levels in the 400s, Butler and other climate scientists said. Until now...It's an important threshold," said Carnegie Institution ecologist Chris Field, a scientist who helps lead the Nobel Prize-winning Intergovernmental Panel on Climate Change. "It is an indication that we're in a different world."
"Carbon dioxide is the chief greenhouse gas and most of it lasts about 100 years in the air, but some of it stays in the atmosphere for thousands of years. Some carbon dioxide is natural, mainly from decomposing dead plants and animals. Before the Industrial Age, levels were around 275 parts per million. For more than 60 years, readings have been in the 300s, except in urban areas, where levels are skewed. The burning of fossil fuels, such as coal for electricity and oil for gasoline, has caused the overwhelming bulk of the man-made increase in carbon in the air, scientists say."
Though the climate fate of the earth for the next century as it is affected or determined by CO2 is set for the next century (whatever that fate may be), to eventually get that number below 350 ppm is still a goal--to get at the cause of future heating, and give the far future a chance.
Green energy is the most obvious place to start, and despite the continuing failure to deal directly with causes, this is the one area of real positive activity. Part of the reason is its coherence with the present state of the world economy (as the world measures economy), that is in profitable industries and jobs. The UN figures that green jobs could add as many as 60 million jobs globally.
Another piece of this puzzle is the visionary and conscientious entrepreneur who applies the technology, like this one:
"When the developer, Voltaic Solaire, finishes a $1 million rehabilitation of a 19th-century brownstone at 367 Fifth Avenue in Park Slope next year, the facade will be covered with a solar skin and a solar awning will sit on the roof. The panels will generate 18,000 kilowatt hours of energy throughout the year, enough to power all six units in the 7,000-square-foot building. Voltaic Solaire is so confident in its ability to create a “net-zero” building that utilities will be bundled into the rent."
We are also learning (or re-learning) a host of simple measures that add crucial increments to the puzzle of using energy with minimum damage to the climate. One example is simply buildings having white roofs, which reflect rather than absorb heat.
In February, researchers at Concordia University estimated that painting one percent of the world’s urban surfaces white (rooftops and pavement) could reduce CO2 emissions by 130 gigatons over the next 50-100 years. In 2011, global CO2 emissions from fossil fuel combustion reached 31.5 gigatons."
One activist estimates:"painting 5% of the world’s rooftops white per year by 2030 could save enough emissions to equal the world’s carbon output in 2010.“That would essentially turn off the entire world for an entire year,” he says.
Reducing energy used for air conditioning by 20% is significant for this one change, which is deep in folk knowledge anyway, in hot countries. Besides scientific innovation, economic opportunity and particular visionary acts of conscience, there is the willingness and eagerness of ordinary people to make changes to save energy and money, which recent polls (and my anecdotal knowledge) confirm is widespread--perhaps the most universal positive possibility, requiring only information and leadership.
Such changes can conceivably make the near future better than it would otherwise be, and they can contribute to getting these fateful numbers going in the right direction, possibly helping the far future. (Though these numbers inevitably will go back down, if or when human civilization breaks apart.) Such incremental changes are not in themselves sufficient. Nothing now will reverse the changes already underway. The time lag in the events of greenhouse gases in the atmosphere, their active lifetimes which stretch from months to centuries, and the unknown feedback loops, tipping points and cumulative effects are the very definition of fate, though we cannot know precisely what that fate will be. But we must do what we can.
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