Eco-Justice Ministries  

Eco-Justice Notes
The E-mail Commentary from Eco-Justice Ministries

400 and Rising
distributed 5/24/13 - ©2013

400.   Without any elaboration, most of you know what those three digits represent, and why that number has been in the news.

But just to be sure that we're all talking about the same thing: this month the level of carbon dioxide in the atmosphere was measured at over 400 parts per million (ppm). CO2 levels have not been that high in over 3 million years.

(Here's the small print: the news is about the daily average of CO2 readings at the Mauna Loa observatory in Hawaii. CO2 levels fluctuate seasonally, and are somewhat different around the globe. Readings of 400 ppm had already been recorded in the Arctic. They will decline in Hawaii until next fall, and then rise farther over 400 next spring. Expect more news reports when Hawaii's monthly and annual averages top 400 -- which they will.)

400 ppm of carbon dioxide is newsworthy for three reasons. (1) CO2 is a greenhouse gas, and the amount of it in the atmosphere directly impacts the global climate. (2) The amount of CO2 is increasing very rapidly. (3) The CO2 being added to the atmosphere is coming primarily from human impacts, including the large-scale burning of fossil fuels.

For those three reasons, 400 is not an abstraction. It is a milestone, a vivid indicator of humanity's warping of Earth's climate and biosphere.

There is, of course, not much difference between a reading of 399.9 and one of 400.1. The round number of 400 is a symbolic transition more than a biochemical one. But those transition points are important to us.

You're really not much different on the day before your 30th birthday than you are a day later (except for that nagging headache from the birthday celebrations). And New Years Day is just another box on the calendar, except for the meaning that we place on the turning of the year.

Those transition points are important occasions for us to reflect on who we are and what we're doing. The ones that have zeros on the end tend to evoke more significant evaluations. I hope that 400 ppm catches our collective attention, and leads us to both reflection and to social change.

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Elizabeth Kolbert, who writes -- very accurately and very well -- about climate in The New Yorker, said a few days ago that the annual ratcheting up of CO2 levels is "a pattern that started out as terrifying and may be now described as terrifyingly predictable." Each year, the numbers go up, and they are going up faster and faster.

When researcher David Keeling started to track the levels of CO2, in 1958, he found a level around 315 ppm. That was 55 years ago. We've gone up 85 ppm since then -- a 27% increase.

The Mauna Loa observatory has not recorded an average monthly CO2 reading below 350 ppm since October 1988. In 25 years, we've gone up 50 ppm.

In the fall of 2009, when launched their first global day of action on climate change, their graphics showing the importance of the grassroots campaign said "We're here: 390.18 ppm. We need to get below here: 350 ppm." But we haven't turned the numbers down toward the "safe" level of 350. We've gone up 10 ppm in under 4 years.

Geochemist Ralph Keeling -- the son of David -- is continuing to measure CO2 at Hawaii. He told a reporter, "I wish it weren't true, but it looks like the world is going to blow through the 400-ppm level without losing a beat. At this pace we'll hit 450 ppm within a few decades."

Even at 400 ppm, we're seeing significant changes in Earth's climate, and the current levels of CO2 will keep adding to global warming for thousands of years. If we keep moving toward 450 ppm, the impacts will be even stronger and more disruptive.

National Geographic has a very informative article about crossing the 400 ppm threshold. The story notes: "The last time the concentration of Earth's main greenhouse gas reached this mark, horses and camels lived in the high Arctic. Seas were at least 30 feet higher -- at a level that today would inundate major cities around the world." The changes that are coming with higher CO2 levels are profound.

James Gustave Speth, in the opening pages of his book, "The Bridge at the Edge of the World", has provided a vivid assessment of where we are headed.

How serious is the threat to the environment? Here is one measure of the problem: all we have to do to destroy the planet's climate and biota and leave a ruined world to our children and grandchildren is to keep doing exactly what we are doing today ... Just continue to release greenhouse gasses at current rates ... and the world in the latter part of this century won't be fit to live in. But, of course, human activities are not holding at current levels -- they are accelerating, dramatically. ... We are thus facing the possibility of an enormous increase in environmental deterioration, just when we need to move strongly in the opposite direction.

None of the experts that I have read -- scientists, ethicists, economists, politicians -- suggest that "moving strongly in the other direction" will be easy. Indeed, most of them acknowledge that slashing the use of fossil fuels and making other equally immense changes is a challenge greater than humanity has ever faced.

But crossing that 400 ppm threshold reminds us that we can not avoid enormous challenges. We either can choose to cut greenhouse gas emissions and make intentional decisions about how to restructure our global society, or we will be forced to deal with a world plummeting into ecological and geopolitical chaos. The challenges are coming. Our only choices are about whether to address them carefully.

Elizabeth Kolbert wrote, "If we take the future at all seriously, which is to say as a time period that someone is going to have to live in, then we need to leave a big percentage of the planet's coal and oil and natural gas in the ground. These basic facts have been established for decades, and every President since George Bush senior has vowed to do something to avert catastrophe. The numbers from Mauna Loa show that they have failed."

The challenges are huge, but there are many arenas in which strong resistance and real change are taking place. There are effective and growing efforts to make the transition from a fossil fuel dependant society, and to leave coal, oil, gas and tar sands in the ground. The call to have universities and churches divest from fossil fuels is another face of the movement to slow the "terrifyingly predictable" rise of CO2.

400 ppm is a symbolic threshold, and symbols are powerfully important. Crossing that line provides us with an opportunity to recognize where we are headed. It is an opportunity to commit ourselves to change, for the sake of future generations and a livable planet.

May we claim this opportunity, and not blow through it without losing a beat. In our churches, our communities, and in the broader society, may we act quickly and dramatically to break our fossil fuel addiction, and to turn toward a more livable future.


Peter Sawtell
Executive Director
Eco-Justice Ministries

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