Archive for the ‘climate adaptation’ Category
|Natural climate factors unlikely to put the brakes on greenhouse-gas-driven sea level rise this century
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):
- With the assumption that sea level will continue to respond over the next 100 years to the same forcings that have influenced it during the past 1000 years, we estimate 0.6 -1.6 m of global sea level rise in the 21st century using a statistical model driven by projected natural and anthropogenic forcings.
- In contrast to the 20th century sea level rise that was associated with a significant contribution of 25% from natural (solar and volcanic) forcing, 21st century sea level rise will be clearly dominated by the changes in CO2 and other greenhouse gases.
- Alternative scenarios for solar forcing with a potential decrease in solar irradiance of 1W/m2 (using the lowest level recorded throughout the last 9300 years) only produce a 10-20 cm reduction in our estimate of 21st century sea level rise.
- If we utilize the 13th century past volcanic forcing to estimate a possible (but unlikely) contribution from volcanic activity, then an almost negligible 8 cm decrease is projected in the estimated sea level rise.
- The suggested reduction of radiative forcing by injections of SO2 into atmosphere (equivalent to a Pinatubo eruption every 4 years) would be equivalent to delaying sea level rise by 12 -20 years.
- A “no changes in radiative forcing” scenario produced 16-22 cm (with lower limit of 10 cm and upper limit of 31 cm) sea level rise in the 21 century due to the inertia of the climate system, providing evidence that conditions established during the past centuries have already committed us to a considerable global sea level rise during the next 100 years.
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 »
Can we alter climate by installing white roofs?
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 »
Extreme climate and the vulnerability of least-developed countries
Wednesday, January 6th, 2010
Happy New Year, everyone. Sorry for the lag in posts, but there wasn’t a lot happening in the news or journals over the past week.
A few years ago, I saw a talk by Thomas Schelling (Nobel laureate in economics) who argued that we need to accelerate the economic development of poor countries so that they are able to cope with climate change. This analysis is interesting, if not fraught with additional challenges, such as development in a carbon-based energy world hastening the very problem to which these nations are attempting to adapt.
In an article1 in the Early Edition of the Proceedings of the National Academy of Sciences (open access), Anthony Patt and colleagues argued that the need for assistance by Least Developed Countries (LDCs) is dependent on vulnerability, which, in turn, depends on both exposure to climate change and how socioeconomic factors affect the sensitivity of LDCs to climate change.
To assess this hypothesis, they first examined how deaths caused by disasters (floods, droughts, and storms) varied across the level of development in several LDCs. They used the UN Human Development Index—HDI, a composite metric of income, education, and life expectancy—as a proxy for development.
Here’s what they found…
Posted in climate adaptation, climate economics, policy, race and class, risk analysis, social science, sustainable development | No Comments »
Where might farmers turn for help with climate change?
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:
- social networks/experiential learning
- government
- industry (e.g., seed, machinery)
- producer and conservation organizations
- media
Here’s what they found…
Posted in climate adaptation, communication and framing, food and agriculture, nature and culture, policy | No Comments »
Ecosystem stewardship: sustainability strategies for a rapidly changing planet
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 »
When the levees break, we’ll have a more sustainable landscape again
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
- Move to flood-tolerant activities in floodplains so that we don’t have to spend so much on disaster relief.
- Storing water in floodplains takes the strain off downstream regions because floodwaters can naturally spill to where they are supposed to rather than swelling channelized rivers. Small amounts of land can accomplish this—they cite a study of the Illinois River showing that a floodplain of 8,000 hectares would drop the likelihood of flooding 26,000 hectares of cropland by 50%.
(2) Increased floodplain goods and services
- Several economic activities are conducive to periodic flooding: pasture, timber, and flood-tolerant biofuel crops, such as willow.
- Periodically flooded soils can also assist with reducing erosion and storing nutrients that would otherwise reach and pollute coastal oceans.
(3) Building resiliency to climate change
- They argue that reconnecting rivers to floodplains can help us adapt to climate change in ways that are socioeconomically beneficial. For instance, we presently have to keep some reservoirs partially empty to accommodate periodic flood waters. But partially filled reservoirs can’t generate as much hydropower or provide as much drinking water. If we used floodplains as a natural pressure relief valve, we can operate reservoirs closer to capacity and benefit economically.
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 »
Will women bear the brunt of climate change impacts?
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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Posted in behavior, climate adaptation, environmental justice, gender, higher education | No Comments »
In this week’s issue of Science: Bangladesh at the front lines of adaptation
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:
- salt water incursion as sea level rises, affecting water supplies and crops along the coast
- concentration of rainfall events into fewer but heavier downpours, which leads to both drought in winter months (and failure of crops) as well as severe floods during the summer monsoons that wipe out crops and destroy infrastructure
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 »
Chicago 1995: How social disparities lead to environmental disasters
Thursday, October 29th, 2009
As I mentioned in the last post, heat waves have the potential to harm or kill a lot of people. Who are the people most likely to suffer first? The experiences from the Chicago 1995 heat wave offer some insights for urban America. Eric Klinenberg’s 2002 book Heat Wave: A Social Autopsy of Disaster in Chicago is as relevant as ever to the current conversation about climate change.
Some excerpts from a U. Chicago Press interview with Klinenberg.
The heat made the city’s roads buckle. Train rails warped, causing long commuter and freight delays. City workers watered bridges to prevent them from locking when the plates expanded. Children riding in school buses became so dehydrated and nauseous that they had to be hosed down by the Fire Department. Hundreds of young people were hospitalized with heat-related illnesses. But the elderly, and especially the elderly who lived alone, were most vulnerable to the heat wave.
“It’s hot,” the mayor told the media. “But let’s not blow it out of proportion. . . . Every day people die of natural causes. You cannot claim that everybody who has died in the last eight or nine days dies of heat. Then everybody in the summer that dies will die of heat.” Many local journalists shared Daley’s skepticism, and before long the city was mired in a callous debate over whether the so-called heat deaths were—to use the term that recurred at the time—”really real.”
[T]he black/white mortality ratio was 1.5 to 1.
Another surprising fact that emerged is that Latinos, who represent about 25 percent of the city population and are disproportionately poor and sick, accounted for only 2 percent of the heat-related deaths…Chicago’s Latinos tend to live in neighborhoods with high population density, busy commercial life in the streets, and vibrant public spaces. Most of the African American neighborhoods with high heat wave death rates had been abandoned—by employers, stores, and residents—in recent decades. The social ecology of abandonment, dispersion, and decay makes systems of social support exceedingly difficult to sustain.
The heat wave was a particle accelerator for the city: It sped up and made visible the hazardous social conditions that are always present but difficult to perceive. Yes, the weather was extreme. But the deep sources of the tragedy were the everyday disasters that the city tolerates, takes for granted, or has officially forgotten.
Related Post: Say so long to your furnace and hello to a new air conditioner
photo credit: http://www.flickr.com/photos/paraflyer/ / CC BY-ND 2.0
Posted in climate adaptation, environmental justice, race and class, social science, urban | 2 Comments »
Climate adaptation: We have no choice, and it’s not enough
Saturday, October 24th, 2009
Our global environment is changing in ways that we are beginning to observe in our lifetimes:
- Climate is warming by as much as a degree centigrade per decade in parts of the Polar North.
- Permafrost is thawing.
- Species ranges are shifting northwards in latitude and upwards in altitude.
- Sea level is rising.
- Sea ice is shrinking.
- Polar ice is thinning.
- Pervasive droughts are beginning to grip parts of the world.
- 50 and 100 year rain storms are happening multiple times in a decade.
- Warming is wreaking havoc on cultures around the world. Inuit communities are losing their villages and traditional hunting grounds. Bangladeshi farmers are losing their coastal fields to saltwater incursion. Pacific islanders are poised to lose their atolls. This week, Nature published a story about how the thawing of the Thorthormi Glacier in the Himalayas threatens the nation of Bhutan.
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 »
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