Wednesday, March 10th, 2010
The IPCC 2007 report projected a conservative sea level rise of about 18-59 cm by the year 2100.
Why conservative? Because it mainly accounted for things we know are happening and can measure well—like thermal expansion of the ocean and melting of land glaciers (see here for a discussion of the Kilimanjaro example). What it doesn’t do so well is account for all of the potential ways that the big ice sheets (Greenland and Antarctica) can contribute to sea level rise. Things like ice flow and mass loss are generally assumed to be constant, even though recent research papers discussed in previous posts (here and here) suggest they are accelerating.
Since the publication of the IPCC report in 2007, there have been several studies suggesting that sea level rise will be 1-2 meters or more by 2100 (one example here). One study looked at geological evidence for sea level rise during the previous interglacial period 125,000 years ago, which was 1-2 degrees C warmer than today. Their work indicated that there was a 95% chance that sea level rose by 6 meters (22 feet).
In a forthcoming issue of Geophysical Research Letters, Svetlana Jevrejeva and colleagues used statistical models to project sea level rise by 2100.1 But they also did something else interesting. They looked back several thousands of years to the most extreme events that could cause climate cooling—things like severe volcanic eruptions, which create stratospheric dust clouds that block sunlight.
If events like this were to happen again, they asked, would they cause enough cooling to be able to slow sea level rise caused by greenhouse gases?
The answer is no. There appears to be no natural factors like vulcanism that will significantly slow greenhouse-gas-driven sea level rise that we are already committed to or future sea level rise that we may experience if we continue to emit fossil fuels.
Excerpts (emphasis mine):
1Jevrejeva, S., J. C. Moore, and A. Grinsted (2010). How will sea level respond to changes in natural and anthropogenic forcings by 2100? Geophysical Research Letters : 10.1029/2010GL042947
UPDATE: RealClimate provides more explanation of the IPCC being too cautious about sea level rise.
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Photo Credit: http://www.flickr.com/photos/gsfc/ / CC BY 2.0
Posted in climate adaptation, climate change science, polar ice, sea level rise | No Comments »
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.
Related post: New ideas about how changing vegetation at high latitudes can cause climate warming to accelerate
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Photo credit: http://www.flickr.com/photos/calliope/ / CC BY 2.0
Tags: albedo
Posted in behavior, climate adaptation, climate change science, energy, solutions, sustainability, technology | No Comments »
Saturday, December 12th, 2009

In the Online First edition of Climatic Change, Tyler Tarnoczi and Fikret Berkes assess1,2 the sources and availability of information about climate adaptation to farmers in the Canadian provinces of Manitoba, Saskatchewan, and Alberta.
Farmers rely on several information sources for agricultural practices, which will likely be vital in helping food producers learn how to adapt to climate warming:
Here’s what they found…
Posted in climate adaptation, communication and framing, food and agriculture, nature and culture, policy | No Comments »
Saturday, December 12th, 2009

That’s the title of a new article1,2 by Terry Chapin and colleagues in a forthcoming issue of Trends in Ecology and Evolution.
Human actions are having large and accelerating effects on the climate, environment and ecosystems of the Earth, thereby degrading many ecosystem services. This unsustainable trajectory demands a dramatic change in human relationships with the environment and life-support system of the planet. Here, we address recent developments in thinking about the sustainable use of ecosystems and resources by society in the context of rapid and frequently abrupt change.
To deal with these challenges, they advocate “ecosystem stewardship,” which has three core principles. Here are excerpts of these principles (slightly condensed/adapted by me); please check out the paper for details:
Posted in climate adaptation, nature and culture, policy, risk analysis, solutions, sustainable development | No Comments »
Thursday, December 10th, 2009

We don’t ordinarily think about climate change and land use change as being a synergistic threat to society. However, the combination of impervious surfaces that increase runoff, declining wetlands, levees, and more severe storms pack a quadruple whammy that could lead to some major flooding in the future. From the cool adaptation work done in Keene, NH, we know that much of our infrastructure (roads, bridges, culverts) can’t handle the added stress of streams and rivers with higher discharge. We’re looking at a potential nightmare of increased costs associated with infrastructure damage.
In this week’s issue of Science, Jeffrey Opperman and colleagues argue1 that our historical paradigm of flood control with levees needs to fundamentally change to achieve a more sustainable socioecological system.
Their solution? Tear down some of the levees to allow some floodplains to flood. This can accomplish several goals:
(1) Flood risk reduction
(2) Increased floodplain goods and services
(3) Building resiliency to climate change
Opperman and colleagues acknowledge that there are political hurdles, such as convincing some private landowners that flooding their land can be useful.
But there are creative solutions that have already been deployed. They cite Sacramento as an example: Some farmers allow their crops to flood, serving as a pressure-relief valve when rivers swell, thereby preventing more expensive damage. In return, the farmers are compensated for their crop loss. It’s a win-win situation that presumably costs less than dealing with infrastructure damage or having to build new infrastructure that handles greater flooding.
Another idea is to allow some of these areas to become wetlands and compensate people as part of a wetlands banking system to mitigate the loss of wetlands elsewhere. This would most likely have several ecological benefits, including increasing habitat for wetland-dependent species such as waterfowl and other migrating birds. It would also likely increase vegetation productivity and carbon storage.
It’s interesting to note that they don’t call for an end to economic activity or human use in floodplains. Sure, we probably want to stop building McMansions in flood-prone regions. However, there are several ways we can use floodplains for ecological and economic benefit. These will likely require compensation, but in the long run, it’s cheaper than having to re-tool major infrastructure to handle greater discharge with climate warming.
1Opperman, J.J. et al (2009) Sustainable floodplains through large-scale reconnections to rivers. Science 326:1487-1488.
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Photo credit: http://www.flickr.com/photos/doblonaut/ / CC BY-NC-SA 2.0
Posted in biodiversity science, climate adaptation, food and agriculture, risk analysis, solutions, sustainable development | No Comments »
Wednesday, November 18th, 2009

Lydia DePillis has an interesting article over at The New Republic based on a new report from the United Nations.
Is climate change gender-neutral? Not according to the U.N. Population Fund, which earlier today released a report arguing that women suffer disproportionately from the impacts of global warming. Especially in developing countries, they can’t flee changes like desertification and sea-level rise as easily as young men, who aren’t as tied to children and households. They’re often caught up in civil conflicts ignited by scarce resources. And they’re more likely to fall victim to diseases caused by wetter weather patterns.
But on the flipside, the report argues, women are also in the best position to help mitigate both the causes and effects of rising temperatures—which is why policies to empower women, like targeted microloans and reproductive healthcare, shouldn’t be treated as separate from climate policy.
…Think of it as Nick Kristof meets Tom Friedman: keeping “women’s issues” separate from “climate issues” is a huge missed opportunity.
I love this conclusion. It’s one of the things that environmental studies (ES) programs in higher education need to focus on—better connections to groups not traditionally affiliated with ES, such as Gender and Women’s Studies, Africana Studies, Psychology, Religion, visual and performing arts, etc. For major environmental challenges like climate warming, everyone needs to be part of this conversation.
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Photo credit: http://www.flickr.com/photos/oxfam/ / CC BY-NC-ND 2.0
Posted in behavior, climate adaptation, environmental justice, gender, higher education | No Comments »
Friday, October 30th, 2009
In “Hot, Flat, Crowded—And Preparing for the Worst“,1,2 (subscription required) Mason Inman lays out how Bangladesh is already coping with climate change.
Bangladesh is being hit with multiple kinds of challenges:
Some excerpts:
Bangladesh is striving to become a global showcase for climate change adaptation. Earlier this month, its government approved a wide-ranging strategy for dealing with climate change that includes ramping up civil engineering projects to control flooding and protect farmland from rising sea levels. Researchers here are also testing crops that better tolerate floods and drought. Realizing that time-honored approaches to living off the land no longer suffice, Bangladesh has implemented more community-level projects than any other country to gird people for climate shifts.
The World Bank estimates that as much as $100 billion a year is required to prepare people in vulnerable areas for climate change. That’s assuming the world gets its act together to rein in greenhouse gas emissions. If not, says disaster expert Ian Burton of the University of Toronto in Canada, “then the cost of adaptation is going to be enormous.”
It would be interesting for someone to estimate what the more-catastrophic adaptation cost scenarios look like compared to mitigation costs. This would make it clear what it costs to mitigate now vs. trying to adapt later when it’s more difficult to do so (if at all possible by that point).
We essentially have four choices:
(1) mitigate now, adapt now
(2) mitigate now, adapt later
(3) mitigate later, adapt now
(4) mitigate later, adapt later
#1 will likely be the least expensive option in the long term, and it will help us sustain the fewest impacts in the near term. It gives us the most flexibility in terms of how we shape the future, and it buys us the most insurance against catastrophic change. The Stern Review suggested global mitigation costs of 1-2% world GDP (about $600 billion-1.2 trillion/yr). That number goes up the longer we wait. A recent Congressional Budget Office estimate of the Waxman-Markey House bill for a U.S. cap-and-trade program was $22 billion/yr (roughly the cost of a postage stamp per day for the average American household) by the year 2020.
By eliminating the up-front costs of adaptation, #2 might appear to save money, but if we don’t adapt to change we are already committed to, the costs associated with warming impacts may be large as we lose coastal real estate and farmland, sustain infrastructure damage from more severe storms and flooding, lose crop productivity, and face public health concerns from things like heat waves. This option is like refusing to pay a few hundred bucks a year for homeowners insurance but then having to pay several hundreds of thousands of dollars to rebuild after a fire.
#3 doesn’t make much sense because we will end up spending twice on adaptation—once to confront near-term changes we are already committed to and once again to deal with (or at least attempt to deal with) conditions getting much worse. Moreover, mitigating later may be too late to avoid potentially dangerous temperature rise, and it reduces our chances of lowering atmospheric CO2 if climate change is irreversible over hundreds of years.
#4 is truly a losers game. Ecologically, socially, and economically, it would likely be catastrophic in all terms.
An ounce of prevention may indeed be worth a pound of cure.
Related post: Climate adaptation: We have no choice, and it’s not enough
1Inman M. (2009) Hot, Flat, Crowded—And Preparing for the Worst. Science 326:662-663.
2Bowdoin people can access the article here.
Posted in climate adaptation, climate change science, food and agriculture, sea level rise | 2 Comments »
Saturday, October 24th, 2009

Our global environment is changing in ways that we are beginning to observe in our lifetimes:
Tim Killeen, head of Geosciences at NSF, once said that if you look at model projections of climate, they all say the same thing up to the year 2030: Based on the gases we have already emitted, and the inertia in the ocean-atmosphere system, we are committed to climate change at least to this point, and there’s little we can do about it. This means we have no choice but to start adapting to things like changing seasonality in temperatures and precipitation, food production, sea level rise, and species distributions. The most recent IPCC synthesis report echoes this.
After 2030, however, models diverge depending on which socioeconomic path we choose. How fast we de-carbonize the economy will determine the extent to which we mitigate warming and how much further adaptation we will need.
There is vigorous debate about the role of adaptation in a world where mitigation is clearly needed. Adaptation has long been assailed by the environmental community as giving up. And now that we need it, old thinking is hard to break.
In a recent article in Yale 360 (Learning to Live With Climate Change Will Not Be Enough), David Orr argues strongly for mitigation over adaptation, although he recognizes that adaptation strategies in the near term are prudent to meet the changes to which we are already committed.
Today, Bowdoin College’s Environmental Studies program, in partnership with the The Nature Conservancy and the McKeen Center for the Common Good, hosted a symposium, “Changing Environments, Changing Societies: Community Responses to Environmental Uncertainty.” It included a mix of international and regional scholars and practitioners, social and natural scientists, and issues like biodiversity, water, food, public health, and infrastructure/urban planning.
What were some of the main outcomes this group synthesized about adaptation?
Posted in behavior, climate adaptation, climate change science, environmentalism, food and agriculture, nature and culture, policy | 2 Comments »