Ann Arbor 350

What is is an international campaign that’s building a movement to unite the world around solutions to the climate crisis–the solutions that science and justice demand. 350 is the most important number in the world! Scientists say 350ppm is the safe upper limit for carbon dioxide in the atmosphere. Find out more on the global site, is building a global grassroots movement to solve the climate crisis with online campaigns, grassroots organizing, and mass public actions led from the bottom up by thousands of volunteer organizers in over 188 countries.

350 means climate safety. To preserve our planet, scientists tell us we must reduce the amount of CO2 in the atmosphere from its current level of 392 parts per million to below 350 ppm. But 350 is more than a number—it’s a symbol of where we need to head as a planet. works hard to organize in a new way—everywhere at once, using online tools to facilitate strategic offline action. The organization is a laboratory for the best ways to strengthen the climate movement and catalyze transformation around the world.

In October of 2009, coordinated 5200 simultaneous rallies and demonstrations in 181 countries, what CNN called the ‘most widespread day of political action in the planet’s history.’ On 10/10/10, they organized the “Global Work Party” — a day of climate solutions projects, from solar panel installations to community garden plantings–and changed communities from the bottom up with over 7000 events in 188 countries.

In 2011, they mobilized people power in every corner of the planet. In September, they organized “Moving Planet” — a massive day of action to move beyond fossil fuels. The group also helped lead the fight to stop the Keystone XL tar sands oil pipeline — a relentless campaign that ended in improbably victory.

If an international grassroots movement holds our leaders accountable to realities of science and principles of justice, we can realize the solutions that will ensure a better future for all.

What is Ann Arbor 350

The world’s top climate scientist, NASA’s Jim Hansen, examined the data and determined that when atmospheric concentrations of carbon dioxide (CO2) were above 350 parts per million (ppm), global warming would be dangerously out of control.

Above 350 and you couldn’t have a planet “similar to the one on which civilization developed and to which life on earth is adapted.”

New data has confirmed Hansen’s conclusion. A British team of climate scientists demonstrated that coral reefs won’t survive acidified waters unless we get carbon dioxide concentrations back down below 360 ppm in our oceans. A European-led team identified the 350 ppm line for carbon as one of nine “planetary boundaries.”

Above 350, they said, we run the risk of “threatening the ecological life-support systems…and would severely challenge the viability of contemporary human societies.”

Unfortunately, the world currently has carbon dioxide levels at 390 ppm and they’re rising by two ppm annually. This means that the work we must do to reduce our carbon footprint is much larger, and must happen much more swiftly, than anyone previously believed.

We believe that change starts with the individual. 

Local, individualized action is critical because climate solutions require innovation, and innovation usually starts on a small scale – like right here in our own back yard.  Understanding the science and believing that each individual can make a difference, we are launching the Ann Arbor 350 campaign.

Ann Arbor 350 is inspired by, a global campaign of people around the world working together to find solutions to the climate crisis. Ann Arbor 350 mobilizes people in the local area to “get Ann Arbor to 350.”  That means that the Ann Arbor area would bring reduce emissions by 80% by 2050 – the path that which, if communities throughout the world did likewise, the world’s concentration of carbon dioxide in the atmosphere would stabilize below the level considered safe for life as we know it on the planet.

The Science of Climate Pollution

350 parts per million is what many scientists, climate experts, and progressive national governments are now saying is the safe upper limit for CO2 in our atmosphere.

Accelerating arctic warming and other early climate impacts have led scientists to conclude that we are already above the safe zone at our current 390ppm, and that unless we are able to rapidly return to below 350 ppm this century, we risk reaching tipping points and irreversible impacts such as the melting of the Greenland ice sheet and major methane releases from increased permafrost melt.

There are three numbers you need to really understand global warming: 275, 392, and 350.

Since the beginning of human civilization up until about 200 years ago, our atmosphere contained about 275 parts per million of carbon dioxide. Parts per million is simply a way of measuring the concentration of different gases, and means the ratio of the number of carbon dioxide molecules to all of the molecules in the atmosphere. 275 ppm CO2 is a useful amount—without some CO2 and other greenhouse gases that trap heat in our atmosphere, our planet would be too cold for humans to inhabit.

So we need some carbon in the atmosphere, but the question is how much?

Beginning in the 18th century, humans began to burn coal and gas and oil to produce energy and goods. The amount of carbon in the atmosphere began to rise, at first slowly and now more quickly. Many of the activities we do every day like turning the lights on, cooking food, or heating or cooling our homes rely on those fossil fuel energy sources that emit carbon dioxide and other heat-trapping gases into the atmosphere. We’re taking millions of years worth of carbon, stored beneath the earth as fossil fuels, and releasing it into the atmosphere. By now—and this is the second number—the planet has about 392 parts per million CO2 – and this number is rising by about 2 parts per million every year.


Scientists are now saying that’s too much – that number is higher than any time seen in the recorded history of our planet—and we’re already beginning to see disastrous impacts on people and places all over the world. Glaciers everywhere are melting and disappearing fast—and they are a source of drinking water for hundreds of millions of people. Mosquitoes, who like a warmer world, are spreading into lots of new places, and bringing malaria and dengue fever with them. Drought is becoming much more common, making food harder to grow in many places. Sea levels have begun to rise, and scientists warn that they could go up as much as several meters this century. If that happens, many of the world’s cities, island nations, and farmland will be underwater. The oceans are growing more acidic because of the CO2 they are absorbing, which makes it harder for animals like corals and clams to build and maintain their shells and skeletons. Coral reefs could start dissolving at an atmospheric CO2 concentration of 450-500 ppm. Along with increased intensity of extreme weather, such as hurricanes and blizzards, these impacts are combining to exacerbate conflicts and security issues in already resource-strapped regions.

The Arctic is sending us perhaps the clearest message that climate change is occurring much more rapidly than scientists previously thought. In the summer of 2007, sea ice was roughly 39% below the summer average for 1979-2000, a loss of area equal to nearly five United Kingdoms.


Propelled by the news of these accelerating impacts, some of the world’s leading climate scientists have now revised the highest safe level of CO2 to 350 parts per million. That’s the last number you need to know, and the most important. It’s the safety zone for planet earth. As James Hansen of America’s National Aeronautics and Space Administration, the first scientist to warn about global warming more than two decades ago, wrote:

“If humanity wishes to preserve a planet similar to that on which civilization developed and to which life on Earth is adapted, paleoclimate evidence and ongoing climate change suggest that CO2 will need to be reduced from its current 385 ppm to at most 350 ppm.”

That will be a hard task, but not impossible. We need to stop taking carbon out of the ground and putting it into the air. Above all, that means we need to stop burning so much coal—and start using solar and wind energy and other such sources of renewable energy –while ensuring the Global South a fair chance to develop. If we do, then the earth’s soils and forests will slowly cycle some of that extra carbon out of the atmosphere, and eventually CO2 concentrations will return to a safe level. By decreasing use of other fossil fuels, and improving agricultural and forestry practices around the world, scientists believe we could get back below 350 by mid-century. But the longer we remain in the danger zone—above 350—the more likely that we will see disastrous and irreversible climate impacts.

With your help, we can spread this important piece of information to our fellow citizens, communities, countries, and the world. For more in-depth information on climate science, policy, and solutions, please see our list of recommended resources below.

For more, read Bill McKibben’s blog post, ”The Science of 350, the Most Important Number on the Planet”


Incredible local resources

Erb Institute at University of Michigan
Global Sustinable Enterprise School which partners between School of Natural Resources and Environment and Ross School of Business
Ross School of Business, 701 Tappan St., 48109
School of Natural Resources and Environment, 440 Church St., 48109

Facility and Operations website
See the sustainable initiatives at the Facilities and operations at University of Michigan

Greenovation TV
Matthew Grocoff
118 S. Main St., Ann Arbor, MI

Green Sight Consulting
Ann Arbor, MI

Huron River Watershed Council
Ric Lawson, Watershed Planner
p: 734.769.5123 x609
f: 734.998.0163
1100 N. Main St., Suite 210
Ann Arbor, MI 48104

Kensington Farm Center
Kensington Metropark
2240 W. Buno Rd
Milford, Michigan 48380

Legacy Land Conservancy
Susan Cooley, Director of Development and Communications
1100 N. Main St. Suite 203
Ann Arbor, MI 48104

Office of Campus Sustainability
Terrance Alexander, PE, CIH, Executive Director
1239 Kipke Drive, Ann Arbor, MI 48109-1010

Planet Blue Teams
Environmental and Energy Initiative
The University of Michigan
UM Plant Operations
Jack Edelstein, Ph.D., Energy Conservation Liaison
326 E. Hoover
Ann Arbor, MI 48109

Recycle Ann Arbor
2420 S Industrial Hwy
Ann Arbor MI 48104

Midwest’s largest farm animal sanctuary
Amanda Hitt, Operations Manager,
Dorothy Davies, Director,
734- 428-9617
17901 Mahrle Rd, Manchester, MI 48158

Selma Café
Friday morning breakfast and hoop house building
Lisa Gottlieb
722 Soule, Ann Arbor, MI 48103

Stewardship Network
Lisa Brush, Executive Director
416 Longshore Drive, Ann Arbor, MI 48105

Wood Window Repair Co.
Works on repairing historic windows and teach others in workshops
Lorri Sipes

Published on February 6, 2015