Tuesday, January 12th, 2010
That’s the title of a new article1 by Suzanne Petroni in the latest issue of Population and Environment (subscription required). She begins by acknowledging the complex history between these issues:
There is, in the field of population and reproductive health, a present debate around the merits and deficiencies of bringing the issue of global population growth back to the public agenda. Many see the current attention to the issue of climate change as an opening in which to make the case that global warming can not be alleviated or reversed without slowing population growth. They believe that linking population growth and climate change will help governments to see the exigency of the matter, and will place family planning back into the political realm as an urgent matter of national and environmental security….
But others worry that focusing on the environmental impacts of demographic change places at risk the hard-fought and long-developed global consensus that individual rights and empowerment are what matters most in fostering just and sustainable development. They fear that a renewed focus on the impacts of the growth of our global population poses a risk of drawing the international community back to numbers-driven policies and programs, which have not always prioritized individual interests…
In light of these huge questions, what are her recommendations?
Monday, January 11th, 2010
When reviewing the most popular words of 2009, I was surprised to see that “albedo” didn’t crack the top 5—Tweet, Obama, H1N1, Stimulus, and Vampire. I bet you were equally shocked.
Albedo is a simple concept—the reflectivity of a landscape—but it’s hugely important in understanding how the surface of the Earth impacts climate. As we saw in a recent post, things like thawing sea ice, northward advancing treeline, and asphalt paving all darken landscapes, causing more solar radiation to be absorbed and temperatures to climb—one of the reasons for the so-called urban heat island effect.
So what would happen if we were to install white roofs? In a forthcoming article1 in Geophysical Research Letters (subscription required), Keith Oleson and colleagues use biophysical models to address this.
Their answer: White roofs reflect more sunlight and cool buildings. Averaged over all urban areas in the world, the urban heat island effect declines by 33%, causing maximum and minimum daily temperatures to decrease by 0.6 and 0.3 degrees C, respectively.
At face value, this sounds great. But, there’s a potential hidden cost of cool buildings—heating. Interestingly, they found that white roofs caused space heating to increase more than air conditioner use declined, suggesting that energy use might actually increase with white roofs!
1Oleson, K. et al. (in press) The effects of white roofs on urban temperature in a global climate model. Geophysical Research Letters.
Monday, January 11th, 2010
Growing sustainability from the bottom-up in any community is challenging. Here’s one way that the Golden Gophers are working on it:
Getting 10,000 people at the University of Minnesota to agree on any one subject is difficult. But 10,000 students, faculty and staff do agree on one thing: saving energy on campus is important.
The U of M has just met its goal of collecting 10,000 energy conservation pledges from students, faculty and staff as part of the It All Adds Up campus energy conservation campaign. The 10,000 pledge marked was topped early Thursday after a flurry of pledges came in response to a university-wide e-mail from President Robert Bruininks asking the Twin Cities Campus to take the pledge.
The university rolled out It All Adds Up last spring in an effort to increase campus awareness about how each person at the U could play a part in saving energy. The energy conservation pledge asks individuals to take seemingly small actions – like turning off lights or powering down computers at the end of the day – with the understanding that if each member of the 80,000 person campus community did those small actions, it would all add up.
Here’s another bottom-up approach, and the FL Gators get a gold star for doing it with one of the hardest behavioral modifications—driving:
The second annual One Less Car challenge was a success, with nearly 1,000 people participating. More than 100 teams represented students, faculty, and staff from departments and units across campus. Together, One Less Car participants avoided over 260,000 miles of driving during the challenge. Through alternative transportation commutes, such as busing, biking, and walking, approximately 246,370 pounds of carbon dioxide were kept from entering the atmosphere.
The teams that used alternative transportation for the most miles were: The Office for Student Financial Affairs, The Florida Museum of Natural History, and The College of Dentistry. Final prizes were awarded to the teams with the highest average points per member: Extreme Backroads, Los Tamales Calientes, Radical Gainesville, Geography, and No glass on the bike lanes. Individuals also earned prizes for logging the most trips and avoiding the most miles of driving. Final prizes included: lunch from Satchel’s Pizza, bike tune-ups, Hippodrome Tickets, Gator Dining meal coupons, and tickets to the Butterfly exhibit at the Florida Museum of Natural History.
For more information: AASHE bulletin 1/1/10
Thursday, January 7th, 2010
Most people have probably heard about positive feedbacks at high latitudes and why they matter:
A new study1 in the Early Edition of the Proceedings of the National Academy of Sciences (open access), indicates that other effects of forest changes might also matter.
Specifically, boreal forests and tundra may become more dominated by deciduous trees (ones that drop their leaves in autumn), which are usually found in warmer regions. What happens if we have a future Arctic dominated by these species?
Using a set of ecosystem and climate models, Abigail Swann and colleagues determined that a rise in deciduous forests would cause an increase in water vapor to the atmosphere (deciduous trees transpire—lose water through their leaves—more than conifers). This makes the atmosphere in the Arctic more laden with water vapor, which is a good greenhouse gas. This warming, in turn, induces further sea ice and snow loss, causing warming to happen more quickly. But wait, there’s more: Warmer, ice-free oceans also release more water vapor to the atmosphere, causing greenhouse warming to increase even more.
How big an effect? About 1 degree C in the Arctic, equivalent to increasing the atmospheric CO2 about 100 ppm in the atmosphere. They found that these changes in water vapor have about the same impact as the changes in reflectivity caused by the color of forest foliage overtopping snow in the tundra.
Things like this are reasons why when warming starts, it can accelerate faster than we think.
1Swann, A. (in press) Changes in Arctic vegetation amplify high-latitude warming through the greenhouse effect. Proceedings of the National Academy of Sciences
Thursday, January 7th, 2010
That’s the title of a column over at Grist by Bowdoin alum, Auden Schendler.
What I like about it is Auden’s emphasis on not waiting for sustainable jobs to slap you in the face. Rather, work to turn any job—your life—into a greener enterprise. Those entrepreneurial skills are tremendously important (Teach a man to fish and he’ll eat forever).
His book, Getting Green Done, is a case study on his doing just that at the Aspen Skiing Company.