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MIT researchers show merits of a carbon tax.

New standards to strengthen vehicle fuel efficiency are considered one of the landmark environmental achievements of President Obama’s first term. Passed with the backing of automakers and autoworkers, the measure has been touted as a way to save consumers more than $1.7 trillion at the pump and cut carbon emissions from passenger vehicles in half. While the standards have many good merits, a more effective approach might be an economy-wide carbon tax, say researchers at MIT’s Joint Program on the Science and Policy of Global Change.

The researchers look at the full energy and economic impacts of the efficiency standards, which in their finalized form now require automakers to install pollution-control technology to improve the fuel efficiency of cars by 5 percent and light trucks by 3.5 percent with each new model year starting in 2017.  Published this month in the journal Transportation Research Record, the study won this year’s Pyke Johnson Award for the best paper in the area of planning and the environment. 

“Common thinking in Washington holds that any policy that seems to advance technology without creating new taxes must be a no brainer for the country. That misses the broader economic impact,” says Joint Program Research Scientist Valerie Karplus, the lead author of the study. “As my colleague says, you may see more money in your front pocket at the pump, but you’re financing the policy out of your back pocket through your tax dollars and at the point of your vehicle purchase.”

Instead, Karplus says a gasoline or carbon tax makes more sense economically by providing consumers a direct incentive to either reduce their driving or buy more efficient vehicles.

“From an economic perspective that’s very clear, but from a political feasibility perspective it’s very different,” she says. Unlike fuel standards that hide the true costs, “a tax on gasoline has proven to be a nonstarter for many decades in the U.S., and I think one of the reasons is that it would be very visible to consumers every time they go to fill up their cars.”

The one hope, Karplus and some of her colleagues at the Joint Program say, is that in the midst of deficit talks a tax on carbon emissions might be considered to help raise the money needed to slash the deficit and avoid some tax hikes and spending cuts. The program published a study in August that looked at the effectiveness of this approach. That study showed that with a carbon tax the economy could overall improve, other taxes could be lowered and pollution emissions would be reduced.

“Congress will face many difficult tradeoffs in stimulating the economy and job growth while reducing the deficit,” says John Reilly, the co-director of the Joint Program and an author of the carbon tax study. “But with the carbon tax there are virtually no serious tradeoffs.”

Conversely, when Karplus and her colleagues simulated the proposed fuel economy standards, they found that while drivers of these more efficient vehicles will likely save at the pump, they could on average spend several thousands of dollars more when buying their new car, consistent with EPA estimates. Even more troubling, diverting efforts toward improved vehicle efficiency distorts overall economic activity, adding to the indirect cost of the policy.

Estimates of how costly the policy would be — in terms of both direct costs to consumers and the larger rippling costs to the economy — hinge on the relative cost of the technology and other strategies available to improve efficiency. The shorter the time frame automakers have to develop the technology and produce more efficient vehicles, the less time there will be for technological progress and other factors to drive down costs — such as the cost of batteries — and the more consumers will need to pay upfront. Emissions and oil imports will initially drop, both due to increased fuel efficiency and as the higher vehicle costs weigh on consumer budgets. But as consumers face lower costs per mile traveled, they may drive more, offsetting reductions in emissions and oil imports.

Karplus hopes her results will help policymakers make more informed decisions going forward. She credits that to the innovative — and award-winning — method she used, which weaves engineering and technology constraints into a broad economic framework and allows researchers to test the cost and other impacts of a policy at different levels of stringency. This method inherently takes account of life-cycle emissions as well as impacts that transmit across fuel markets by affecting prices.

For example, a policy might only consider gasoline use by plug-in electric hybrids. But that “tailpipe measure” doesn’t take into account the emissions created from building, transporting and recharging those batteries. Her approach does.

“There are a lot of hidden costs to a policy like this,” Karplus says. “This model doesn’t allow you to ignore other important aspects of the economy and energy systems. It requires you to be explicit about your technology and cost assumptions.  It provides a framework that allows lawmakers to look at all the available information on costs and the state of the technology and decide how to best create or update policies.”

Of this approach, University of Maine environmental economist Jonathan Rubin, says “The research of Dr. Karplus on the energy and climate impacts of the nation’s fuel economy standards for our cars and trucks makes an important contribution to policymaking based on science.”

Rubin is the chair of the Transportation Energy Committee of the Transportation Research Board, which will honor Karplus with the Pyke Johnson award at a ceremony in January.

By: Dylan Matthews

Grover Norquist made headlines Monday night for saying that while he thinks a “carbon tax swap” — in which such a tax finances cuts to the income tax — is bad policy, he doesn’t think it violates his anti-tax pledge. This isn’t as big a deal as you might think, not least because the chances of a carbon tax were always slim, but it does raise the question: What would a carbon tax swap actually look like?

A paper in August by MIT’s Sebastian Rausch and John M. Reilly — which Brad highlighted upon release — asks how much you could cut various taxes if you imposed a carbon tax, starting at $20 per ton in 2013 and increasing by 4 percent every year thereafter. The answer: not that much.

The first table below shows how much you could cut various taxes if 100 percent of carbon tax revenues are used to finance the cuts. The second table shows potential cuts if only half of the revenue goes to other cuts. The latter scenario seems likelier as part of a deficit reduction deal, as the former would be revenue-neutral and thus do nothing to balance the budget:

Source: Rausch and Reilly

In 2015, a 100 percent swap would only allow income tax rates to fall 0.59 percentage points, relative to all the Bush tax cuts expiring. So the top rate would be 39 percent rather than 39.6 percent. That’s hardly a game-changer. The possible income tax cuts are barely perceptible when only half of revenue funds rate reductions.

The situation is a bit more promising for tax and corporate taxes. A full swap would finance a 1.59 point reduction in the payroll tax in 2015, almost as much as the two point cut in place for the past two years. Alternately, it would allow the corporate income tax rate to drop below 33 percent from its current level of 35 percent.

Rausch and Reilly found that cutting the corporate (blue line) or personal (red) income tax as part of a swap would be regressive, but using it to pay for a payroll tax cut (black) or social programs for the poor like Medicaid (green) would be highly progressive. Here’s how each would affect the incomes of people across the income spectrum:

Source: Rausch and Reilly

The Medicaid option is a big boon for people making up to $75,000, and a net tax increase above that point. A payroll tax cut benefits everyone but those making over $150,000, while personal or corporate tax cuts help everyone but the very poor.

Another option, proposed by Gilbert Metcalf, a Tufts economist currently heading up the environmental tax division at Treasury, is using a carbon tax to fund an exemption in the payroll tax. Currently, Social Security taxes apply to the first dollar you earn, until you reach the cap (currently $110,100). Metcalf finds that a $15 per ton carbon tax would allow the government to exempt the first $3,660 a given worker earns from the payroll tax, similar to how personal exemptions allow all income tax payers to exempt the first few thousand dollars they earn.

Metcalf’s plan would be more regressive than the ones Rausch and Reilly looked at. The bottom 30 percent of the income distribution would see taxes increase by as much as 1.1 percent of income, while middle class people would see modest tax cuts and the very rich would be unaffected. That suggests that policymakers concerned with progressivity would do better to use a carbon tax to fund entitlements or a payroll tax rate cut than an exemption.

(The author is a Reuters market analyst. The views expressed are his own.)

By Gerard Wynn

(Reuters) - Academics and lawmakers have proposed a U.S. carbon tax to curb carbon emissions and trim the debt pile, but the idea depends on prominent Republican support, so far absent.

Without a deal on cutting the fiscal deficit the United States faces a $600 billion package of automatic tax increases and spending cuts which could tip the country back into recession.

While that is clearly a step too far, the consensus is that a more gradual combination of spending cuts and/or tax hikes is required to avoid a borrowing crisis.

Many economists have argued for a carbon tax: it would lead to net welfare benefits compared with for example hikes in income tax, even before allowing for avoided climate change.

But it faces formidable problems.

It would acknowledge a climate threat, hike energy prices, hurt U.S. competitiveness (without including complicated compensating measures), and sound very much like a failed cap and trade bill.

To progress, supporters would have to paint a nightmare alternative including cuts in defense and social spending and income tax rises, and demonstrate clear daylight with a proposed cap and trade scheme which failed to win Congress approval in 2009.

Some energy executives and notably Exxon's chief executive have previously said they much prefer a carbon tax.

A cap and trade bill only narrowly passed the House of Representatives by 219-212 in June 2009 before mid-term elections saw Republicans take a House majority, and failed to pass the Senate.

PRICE

A carbon tax, or cap and trade scheme makes emitters pay for climate damage from burning fossil fuels and so drives a shift towards cleaner alternatives.

The notion of using carbon pricing to cut the U.S. budget deficit dates back to the Congressional Budget Office (CBO) report in March 2011, "Reducing the Deficit: Spending and Revenue Options."

The CBO reviewed cap and trade, or a carbon tax among 104 other options for raising tax revenues or cutting spending.

It reported that a scheme which applied a carbon price of $20 tax per tonne of CO2 would raise nearly $1.2 trillion by 2021.

Costs would be passed to energy consumers, its biggest political problem not always mentioned by economists, requiring some compensation which would steal funds from deficit cutting.

"The government could use some of those revenues to accomplish various goals such as reducing taxes, offsetting the costs of the cap-and-trade programme for certain groups or industries that are put at a competitive disadvantage by the programme, or reducing the federal deficit," the CBO report said.

ECONOMICS

A Massachusetts Institute of Technology (MIT) study in August found that a carbon tax would have a net economic benefit compared with allowing certain Bush-era tax cuts to expire, while still cutting the deficit.

Effectively they would swap one tax (on income, if Bush cuts expire on December 31) for another (on carbon).

The authors attributed the net economic benefit to a greater "drag" on the economy from income tax than a carbon tax.

The study did not quantify other benefits such as avoided climate change or lower crude oil imports, or try to compensate energy consumers.

"Given that all other options for dealing with the Federal deficit require difficult tradeoffs, it would seem hard to pass up one that offers so many advantages," the authors concluded in their paper "Carbon Tax Revenue and the Budget Deficit: A Win-Win-Win Solution?".

As Joseph Stiglitz said, in support of a carbon tax in his 2006 book "Making Globalisation Work":

"The country as a whole might be better off; it can use the revenue from the carbon tax to reduce other taxes, such as those on savings, investment, or work. These lower taxes would stimulate the economy, with benefits far greater than the cost of the carbon tax. This is consistent with a general economic principle: it is better to tax things that are bad like pollution than things that are good like savings or work."

ENERGY

Support from economists is one thing.

Given expected higher fossil fuel energy prices and therefore lower consumption, an endorsement by Exxon Chief Executive Rex Tillerson three years ago was more startling.

But that was in the context of shooting down cap and trade proposals when no alternative tax was suggested, and may therefore be more significant for rejecting one than supporting the other.

"As a businessman it is hard to speak favorably about any new tax. But a carbon tax strikes me as a more direct, a more transparent and a more effective approach (than cap and trade). It could be levied under the current tax code without requiring significant new infrastructure or enforcement bureaucracies," Tillerson told a Washington energy security conference in 2009, as quoted in the Exxon journal "The Lamp".

"A carbon tax is also the most efficient means of reflecting the cost of carbon in all economic decisions - from investments made by companies to fuel their requirements to the product choices made by consumers.

"Such a tax should be made revenue neutral. In other words, the size of government need not increase due to the imposition of a carbon tax. There should be reductions or changes to other taxes - such as income or excise taxes - to offset the impacts of the carbon tax on the economy."

POLITICS

The biggest practical problem of a carbon tax is softening its impact on energy consumers and energy-intensive industries.

The European Union has demonstrated that distribution problems can be solved, where for example power plants in poorer east European countries face a softer transition, and factories which face international competition get free emissions permits.

But political efforts now to raise European carbon prices face opposition from some member states, concerned about higher energy prices, even though it would raise funds for government coffers, in the same way as a U.S. tax.

In the face of undoubted, entrenched opposition from certain stakeholders including energy-intensive manufacturers and farmers, the only chance for a carbon tax in the United States is if Democrats prioritize it, and Republicans accept it as the least-worst option, for environmental legislation.

By: Steven Mufson, November 9

Here’s a riddle: If Congress doesn’t want to raise income tax rates but wants to raise revenue, what can it do?

One answer: Pass a carbon tax.

A relatively moderate-sized carbon tax could raise $1.25 trillion over the next decade, a huge chunk of the money needed to bring the federal budget deficit under control. And the idea is getting a closer look now that the election is over and the “fiscal cliff” is looming.

Because it would tax fossil fuel use, the carbon tax pleases economists who want to encourage investment and discourage consumption. Climate activists hope it would reduce greenhouse-gas emissions by penalizing the use of coal, oil and natural gas. And for lawmakers opposed to any change in tax rates or deep cuts in spending, the carbon tax could be a lifeline.

“In the general scheme of things, taxes discourage whatever you’re taxing,” said William Pizer, associate professor of economic and environmental policy at Duke University. “If something is discouraged, it might as well be something bad like pollution instead of employment and savings.”

Pizer said that a $20-a-ton tax on carbon dioxide would raise gasoline prices by about 20 cents per gallon and boost electric bills slightly. It could be most efficiently collected “upstream,” at coal mines, oil and gas wells, or terminals for oil tankers arriving at U.S. shores.

There are drawbacks. Higher prices fall most heavily on lower-income earners who spend a larger portion of their pay on fuel. The tax would hurt certain regions more than others. It would need to be tweaked to protect firms that export to countries where companies don’t pay any carbon tax. It would also have to be reconciled with existing carbon trading schemes in the Northeast and California.

“Taxation is a painful thing, but this is one of the least inefficient ways of raising taxes,” said Nick Robins, head of the climate change center for banking giant HSBC. “At a time of low economic growth, it can be quite a good thing because it is taking costs out of the economy. If you can do that, it would be a good thing.”

As a matter of negotiating strategy, now might be a bad time for the Obama administration to advertise interest in a carbon tax. Doing so would make it a “lightning rod,” said Pizer, a former Treasury official. But, he added, once people see the pros and cons of other taxes and once they reach an impasse and need more revenues, a carbon tax might be an attractive alternative.

“From a policy-making point of view, it is clear that there is no way that this Congress is going to glom onto a carbon tax as an environmental policy,” said Philip R. Sharp, who served two decades in the House and is now president of Resources for the Future. “But it could become an important enabler for other things the Congress wants to do, namely eliminating the deficit and tax reform.”

In the past, conservatives have supported the idea of a carbon tax, though most of them have opposed using the receipts to swell government coffers.

N. Gregory Mankiw — a Harvard University economics professor, adviser to GOP presidential nominee Mitt Romney and former chairman of President George W. Bush’s Council of Economic Advisers — has long supported a carbon tax because he says the price of fossil fuels doesn’t reflect their true societal costs. In the past, he said he would use the receipts to lower other taxes.

In 2007, Kevin Hassett of the American Enterprise Institute, said a carbon tax would not only help energy security and attack global warming, it could also raise a quarter as much revenue as the corporate income tax and could be used to cut those rates.

In 2009, Exxon Mobil chief executive Rex Tillerson — in part to slow momentum toward a cap-and-trade system for reducing greenhouse-gas emissions — endorsed the carbon tax and said it should be set “somewhere north of” $20 a ton.

“As a businessman it is hard to speak favorably about any new tax. But a carbon tax strikes me as a more direct, a more transparent and a more effective approach,” he said at the time. He added that “a carbon tax is also the most efficient means of reflecting the cost of carbon in all economic decisions — from investments made by companies to fuel their requirements to the product choices made by consumers.”

But he, too, said it should be revenue neutral.

One leading GOP advocate of the carbon tax just flipped position. House member and Sen.-elect Jeff Flake (R-Ariz.) co-sponsored a carbon tax bill in 2009. But Friday, a spokesman told The Hill newspaper that Flake “has no plans to reintroduce it or support it as part of a tax reform package.”

The American Petroleum Institute (API) opposes a carbon tax. “Anytime we look at an energy issue, be it a tax or regulatory issue, we ask what does it do to promote or inhibit energy production and what is the impact on the American people,” said Jack Gerard, API president. “Clearly, it would increase costs to the American public. Is that what he [President Obama] wants to do? I would think not.”

But compared to the fiscal cliff , even a carbon tax might look attractive. A study by the Massachusetts Institute of Technology said “the economy is better off with the carbon tax than if taxes remain high to maintain Federal revenue.”

“We’ve been just surprised at the number of political groups across the political spectrum considering this,” said Sharp of Resources for the Future. “Contrary to what almost everybody universally would have said two years ago, we have gotten ourselves in such a pickle on the fiscal side of things that it opens up the possibility.”

MIT researchers develop tool to assess regional risks of climate change, potential impacts on local infrastructure and planning.

Climate scientists cannot attribute any single weather event — whether a drought, wildfire or extreme storm — to climate change. But extreme events, such as Hurricane Sandy, are glimpses of the types of occurrences the world could be more vulnerable to in the future. As the devastation left by Sandy continues to reverberate, decision-makers at every level are asking: How can we be better prepared?

MIT researchers have developed a new tool to help policymakers, city planners and others see the possible local effects of climate change. Its regional projections of climate trends — such as long-term temperature and precipitation changes — allow local planners to evaluate risks, and how these risks could shape crops, roads and energy infrastructure.

“As we see more extreme events like Sandy, the importance of assessing regional impacts grows,” says lead researcher Adam Schlosser, assistant director for science research at MIT’s Joint Program on the Science and Policy of Global Change. “Our approach helps decision- and policy-makers balance the risks … so they can better prepare their communities for future impacts climate change might bring.”

For example, Schlosser says, if a community is planning to build a bridge, it should look at — and plan for — the expected magnitude of flooding in 2050.

“In areas devastated by Sandy, the rebuilding of lost property and infrastructure will come at considerable cost and effort,” Schlosser says. “But should we rebuild to better prepare for future storms like these? Or should we prepare for stronger and/or more frequent storms? There remains considerable uncertainty in these projections and that implies risk. Our technique has been developed with these questions in mind.”

Schlosser’s research partner, Ken Strzepek, a research scientist at the Joint Program on the Science and Policy of Global Change, notes policymakers are now often given little more than a set of extreme circumstances to consider.

“Policymakers don’t like extremes or worst-case scenarios,” Strzepek says, “because they can’t afford to plan for the worst-case scenarios. They like to see what is the likelihood of different outcomes. That’s what we’re giving them.”

Getting results

In this new method, the researchers quantify the likelihood of particular outcomes and add socioeconomic data, different emission levels and varying degrees of uncertainty. Their technique combines climate-model projections and analysis from the Coupled Model Intercomparison Project used by the Intergovernmental Panel on Climate Change, and the MIT Integrated Global System Modeling (IGSM) framework. The MIT framework is itself a combined computer model that integrates an economic, human system with a natural, earth system.

“This approach allows us to widen the scope and flexibility of climate analysis,” Schlosser says. “It provides us with efficient capabilities to determine climate-change risks.”

The initial study using this approach — accepted by the Journal of Climate and available on the journal’s website — compares a business-as-usual case with a scenario that reduces emissions. The researchers find that lowering emissions reduces the odds of regional warming and precipitation changes. In fact, for many places, the likelihood of the most extreme warming from the business-as-usual case could be eliminated almost entirely.

The study finds diverse climate-change outcomes: southern and western Africa, the Himalayan region, and the area around Hudson Bay in Canada are expected to warm the most; southern Africa and western Europe see the greatest chance of drier conditions. Meanwhile, the Amazon and northern Siberia may become wetter.

Putting the method to work

Schlosser and Strzepek are pursuing partnerships with communities to put their method to work. But while it’s important for every community to begin building climate adaptation into its infrastructure plans, developing countries could reap the greatest benefits.

Malcolm Smart, senior economic adviser for the U.K. Department for International Development, who was not involved in this research, says, “This is not only an innovative and multidisciplinary approach to the problem of deep uncertainty, but also a potentially very valuable tool to help vulnerable developing countries cut the cost of damages from climate change.”

Strzepek explains why: In the United States, infrastructure plans are designed based on a high standard of risk, while in developing countries projects are typically built to a lower standard of risk. “But if we find that [a developing country] will see greater flooding, and if we’re fairly certain of this, then they would save money in the long run if they built roads to withstand those flooding events,” Strzepek says.

Schlosser and Strzepek traveled to Finland earlier this fall to present their research at a United Nations University-World Institute for Development Economics Research conference. They’ve partnered with this organization to inform developing countries of this new tool for assessing climate change.

“Our approach allows decision-makers to cut down on the level of risk they’re taking when allocating their limited funds to development projects,” Schlosser says. “This can help them see where there are economic benefits to taking a risk-averse approach today, before the damage is done.”

Related research: Climate Change: A Developing Challenge for Poor Nations

By: Jennifer Chu, MIT News Office

Susan Solomon, the Ellen Swallow Richards Professor of Atmospheric Chemistry and Climate Science
Photo: Dominick Reuter

In looking for ways to combat climate change and minimize the planet’s warming, atmospheric chemist Susan Solomon says it’s often helpful — and heartening — to look to the past.

Solomon points out that recent decades have seen major environmental progress: In the 1970s, the United States banned indoor leaded paint following evidence that it was poisoning children. In the 1990s, the United States put in place regulations to reduce emissions of sulfur dioxide — a move that significantly reduced acid rain. Beginning in the 1970s, countries around the world began to phase out leaded gasoline; blood lead levels in children dropped dramatically in response. 

During this period, Solomon herself contributed to a milestone in environmental protection: In 1985, scientists discovered that the Earth’s protective ozone layer was thinning over Antarctica. In response, Solomon led an expedition whose atmospheric measurements helped show that chlorofluorocarbons (CFCs) — chemicals then used in aerosols and as coolants in refrigerators and air conditioners — were to blame for ozone depletion. Her discovery ultimately contributed to the basis for the United Nations’ Montreal Protocol, an international treaty designed to protect the ozone layer by phasing out CFCs and other ozone-depleting chemicals.

“I find it tremendously uplifting to look back at how our world has changed,” says Solomon, now the Ellen Swallow Richards Professor of Atmospheric Chemistry and Climate Science at MIT.

Solomon, a renowned atmospheric chemist who worked for 30 years in Boulder, Colo., at the National Oceanic and Atmospheric Administration (NOAA) and as an adjunct professor at the University of Colorado, is continuing her work in climate research at MIT, where she joined the Department of Earth, Atmospheric and Planetary Sciences in January. In addition to her research, Solomon is teaching a course, 12.085/12.885 (Environmental Science and Society), exploring how society has tackled a range of past environmental challenges through science, engineering, policy, public engagement and politics.

“I think young people today are growing up at a time when they don’t know that we actually have made tremendous progress on a whole series of past environmental challenges,” Solomon says. “Climate change has been called the mother of all environmental issues … and I think our approach to this problem can only be better informed if we understand better what we’ve done in the past.”

Heading west

Born in Chicago, Solomon was completely taken, from a young age, with “The Undersea World of Jacques Cousteau,” a documentary series that followed the legendary marine explorer on his seafaring expeditions. “I pretty much never wavered from the decision right then that I was going to be a scientist,” she recalls.

After high school, Solomon enrolled at the Illinois Institute of Technology, where she received a bachelor’s degree in chemistry. Continuing her studies in atmospheric chemistry, Solomon moved west, to the University of California at Berkeley. “I had a 1977 Gremlin,” Solomon recalls. “It was one of the most awful cars, I think, ever made, but it was really cheap, and I was young and poor. I remember listening to … ‘California Dreamin’’ as I drove out west.”

Solomon received her PhD in chemistry from Berkeley in 1981, and went to work as a research scientist at NOAA. In 1985, scientists with the British Antarctic Survey discovered the ozone hole above Antarctica, prompting Solomon to lead expeditions to the icy continent in 1986 and 1987.

“It’s the next-best thing to going to another planet,” Solomon says of the harsh yet exhilarating experience. “It is the place on our planet that is the most unexplored, the most remote, the most hostile in terms of what the weather and climate is. It is so viciously cold. I just thought it was fantastic exploration, and it’s that spirit of exploration that I think is so endemic to science, and is fundamental to everything about Antarctica.”

In 2001, Solomon chronicled perhaps the most dramatic exploration of that continent in a bestselling book, “The Coldest March”: She used scientific data to examine long-held myths about Robert Falcon Scott, an early-20th-century English explorer who trekked more than 1,000 miles on foot in an effort to become the first to reach the South Pole. But Roald Amundsen, a rival explorer, beat him to the pole by a month, and Scott, along with several team members, perished on the long trek back.

While Scott’s expedition had been ridiculed — for example, by some who painted him as a “dyed-in-the-wool Englishman who only wanted to eat tinned mutton,” and therefore died of scurvy — letters and diaries from his crew told a different story. Many members of the team described eating fresh seal meat and seal liver, which have been shown to be a good source of the vitamins that ward off the disease. Solomon also analyzed weather data from 1912, and discovered that the crew likely would have survived had they not encountered extreme and unpredictable weather conditions.

“It just seemed to me that somebody needed to go back and take a closer look, with all the diaries of all the guys, and what we know from modern science,” Solomon says.

Changing the climate

In 2002, Solomon took on another monumental task: leading an international assessment of the scientific work related to climate change. Over six years, she served as co-chair of Working Group 1 of the Intergovernmental Panel on Climate Change (IPCC). In 2007, the group released a comprehensive report on the scientific basis of climate change. Later that year, based in part on the report, the IPCC and former vice president Al Gore received the Nobel Peace Prize.

Solomon continues to seek answers to the most pressing climate challenges. In a widely cited 2009 paper published in the journal Proceedings of the National Academy of Sciences, Solomon and her co-authors determined that, even if humans were to immediately and completely stop emitting carbon dioxide, it would take more than 1,000 years to undo existing changes in Earth’s surface temperatures, rainfall and sea levels.

This news, while sobering, has not deterred the chemist in her scientific goals. Solomon is currently probing which places on the planet are likely to be the most affected by anthropogenic warming in the near future. In addition to her climate research, she also continues to study the stratosphere — the layer of the atmosphere in which the ozone layer is found.

“There are still fantastic surprises in the stratosphere, as there are in any field, no matter how much has been done on it,” Solomon says. “There’s always something to discover, and I love that feeling.”

Read an earlier story about a lecture Susan Solomon gave. 

Whenever there’s an extreme weather event, from a hurricane to a record drought, the question always arises: Is it climate change?

MIT climate scientist Kerry Emanuel told Here & Now's Robin Young that it's hard to know for sure, but it is clear that as coastal waters warm up, storms will carry more rain, due to the added water vapor.

Listen to the interview...

This NOAA satellite image taken on Monday shows Hurricane Sandy off the Mid
Atlantic coastline moving north. (AP/NOAA)

The 2012 drought in America brought to light the challenges we face when there isn't sufficient water to cool our nation's power plants. Conventional fossil-fuel and nuclear power plants require water to cool the steam they generate to make electricity. In 2005, power plants accounted for over 40 percent of all freshwater withdrawn in the U.S. Many power plants need a huge, steady supply of water to operate, and in hot dry summers, that water can become hard to secure.

On October 18, 2012, the Union of Concerned Scientists hosted a webinar discussion on the challenges and opportunities for electricity production in a water-constrained future.

The webinar featured:

Camille Calimlim, committee staff, Water and Power Subcommittee, U.S. House of Representatives, who discussed the energy-water policy landscape and opportunities, including the Energy and Water: Connection and Conflict report prepared by Rep. Edward Markey (D-MA) for the Committe on Natural Resources.

John Rogers, senior energy analyst and co-manager of the Energy and Water in a Warming World Initiative (EW3), Union of Concerned Scientists, who presented on current power plant water use and highlighted the findings from the EW3 report, Freshwater Use by U.S. Power Plants: Electricity's Thirst for a Precious Resource.

C. Adam Schlosser, principal research scientist and assistant director of science research in the Joint Program on the Science and Policy of Global Change, MIT, who discussed the water implications of an 80 percent renewable energy future as articulated in the NREL Renewable Electricity Futures Study for which he was a lead author.

• Listen to the webinar (MP3)
• Download the PowerPoint slides (PDF)

RELATED - News Release: Double the Benefits, Clean Energy Also Saves Water

The policy community has long prophesied about the coming water wars. But don't expect them anytime soon. More likely, tensions over access will merely exacerbate existing regional conflicts.

By: Shlomi Dinar, Lucia De Stefano, James Duncan, Kerstin Stahl, Kenneth M. Strzepek, Aaron T. Wolf

Right: Looking south over the Mediterranean and down the Nile, from the International Space Station. (NASA / flickr)


The world economic downturn and upheaval in the Arab world might grab headlines, but another big problem looms: environmental change. Along with extreme weather patterns, rising sea levels, and other natural hazards, global warming disrupts freshwater resource availability -- with immense social and political implications. Earlier this year, the Office of the Director of National Intelligence published a report, Global Water Security, assessing hydropolitics around the world. In it, the authors show that international water disputes will affect not only the security interests of riparian states, but also of the United States. 

In many parts of the world, freshwater is already a scarce resource. It constitutes only 2.5 percent of all available water on the planet. And only about .4 percent of that is easily accessible for human consumption. Of that tiny amount, a decreasing share is potable because of pollution and agricultural and industrial water use. All that would be bad enough, but many freshwater bodies are shared among two or more riparian states, complicating their management.

Of course, the policy community has long prophesied impending "water wars." In 2007, UN Secretary General Ban Ki Moon warned that "water scarcity ... is a potent fuel for wars and conflict." Yet history has not witnessed many. In fact, the only official war over water took place about 4,500 years ago. It was a conflict between the city-states of Lagash and Umma in modern day Iraq over the Tigris river. More recently, there have been some close calls, especially in the arid Middle East. About two years before the 1967 War, Israel and Syria exchanged fire over the Jordan River Basin, which both said the other was overusing. The limited armed clashes petered out, but the political dispute over the countries' shared water sources continues. In 2002, Lebanon constructed water pumps on one of the river's tributaries, which caused concern for downstream Israel. The project never provoked any formal military action, but with peace in the region already precarious, verbal exchanges between the two countries prompted the United States to step in. Both parties eventually accepted a compromise that would allow Lebanon to withdraw a predetermined amount of water for its domestic needs.

In short, predictions of a Water World War are overwrought. However, tensions over water usage can still exacerbate other existing regional conflicts. Climate change is expected to intensify droughts, floods, and other extreme weather conditions that jeopardize freshwater quantity and quality and therefore act as a threat-multiplier, making shaky regions shakier.

So what river basins constitute the biggest risks today? In a World Bank report we published in 2010 (as well as a subsequent article in a special issue of the Journal of Peace Research) we analyzed the physical effects of climate change on international rivers. We modeled the variability in river annual runoff in the past and for future climate scenarios. We also considered the existence and nature of the institutional capacity around river basins, in the form of international water treaties, to potentially deal with the effects of climate change.

According to our research, 24 of the world's 276 international river basins are already experiencing increased water variability. These 24 basins, which collectively serve about 332 million people, are at high risk of water related political tensions. The majority of the basins are located in northern and sub-Saharan Africa. A few others are located in the Middle East, south-central Asia, and South America. They include the Tafna (Algeria and Morocco), the Dasht (Iran and Pakistan), the Congo (Central Africa), Lake Chad (Central Africa), the Niger (Western Africa), the Nile (Northeastern Africa), and the Chira (Ecuador and Peru). There are no strong treaties governing the use of these water reserves in tense territories. Should conflicts break out, there are no good mechanisms in place for dealing with them.

By 2050, an additional 37 river basins, serving 83 million people, will be at high risk for feeding into political tensions. As is the case currently, a large portion of these are in Africa. But, unlike today, river basins within Central Asia, Eastern Europe, Central Europe, and Central America will also be at high risk within 40 years. Some of these include the Kura-Araks (Iran, Turkey, and the Caucasus), the Neman (Eastern Europe) Asi-Orontes (Lebanon, Syria, Turkey), and the Catatumbo Basins (Colombia and Venezuela).

CROSSING THE NILE

Among the larger African basins, the Nile has the greatest implications for regional and global security. Tensions over access to the river already pit Ethiopia and Egypt, two important Western allies, against one another. Egypt has been a major player in the Middle East Peace Process and Ethiopia is an important regional force in the Horn of Africa, currently aiding other African forces to battle Al-Shabbab in Somalia.

Over the years, a number of international water treaties have made rules for the basin, but they are largely limited to small stretches of it. In particular, only Egypt and Sudan are party to the 1959 Nile River Agreement, the principal treaty regarding the river. Egypt, which is the furthest downstream yet is one of the most powerful countries in the region, has been able to heavily influence the water-sharing regime. Upstream countries, such as Ethiopia and Burundi, have been left out, hard-pressed to harness the Nile for their own needs.

In 1999, with increasingly vitriolic rhetoric between Egypt and Ethiopia sidetracking regional development, the World Bank stepped up its involvement in the basin. It helped create a network of professional water managers as well as a set of investments in a number of sub-basins. Still, the drafting of a new agreement stalled: upstream countries would not compromise on their right to develop water infrastructure while downstream countries would not compromise on protecting their shares. In 2010, Ethiopia signed an agreement with a number of the other upstream countries hoping to balance against Egypt and Sudan. More recently, the country has also announced plans to construct a number of large upstream dams, which could affect the stability of the region.

By 2050, the environmental state of the Nile Basin will be even worse. That is why it is important to create a robust and equitable water treaty now. Such a treaty would focus on ways to harness the river's hydropower potential to satiate the energy needs of all the riparian states while maintaining ecosystem health. The construction of dams and reservoirs further upstream could likewise help even out water flows and facilitate agricultural growth. Projects such as these, mitigating damage to ecosystem health and local populations, would benefit all parties concerned and thus facilitate further basin-wide cooperation.

UP IN THE ARAL

Another water basin of concern is the Aral Sea, which is shared by Kazakhstan, Kyrgyzstan, Tajikistan, Turkmenistan, and Uzbekistan. The basin consists of two major rivers, the Syr Darya and Amu Darya. During the Soviet era, these two rivers were managed relatively effectively. The break-up of the Soviet Union, however, ended that. The major dispute now is between upstream Kyrgyzstan and downstream Uzbekistan over the Syr Darya. During the winter, Kyrgyzstan needs flowing water to produce hydroelectricity whereas Uzbekistan needs to store water to later irrigate cotton fields.

The countries have made several attempts to resolve the dispute. In particular, downstream Uzbekistan, which is rich in fuel and gas, has provided energy to Kyrgyzstan to compensate for keeping water in its large reservoirs until the cotton-growing season. Such barter agreements, however, have had limited success because they are easily manipulated. Downstream states might deliver less fuel during a rainy year, claiming they need less water from upstream reservoirs, and upstream states might deliver less water in retaliation. Kyrgyzstan, frustrated and desperate for energy in winter months, plans to build mega hydro-electric plants in its territory. And another upstream state, Tajikistan, is likewise considering hydro-electricity to satiate its own energy needs. Meanwhile, Uzbekistan is building large reservoirs.

Although these plans might make sense in the very near term, they are inefficient in the medium and long term because they don't solve the real needs of downstream states for large storage capacity to protect against water variability across time. In fact, both Kyrgyzstan and Uzbekistan, along with Kazakhstan, will see substantial increases in water variability between now and 2050. And so, the need to share the benefits of existing large-capacity upstream reservoirs and coordinate water uses through strong and more efficient inter-state agreements is unavoidable.

A stabilized Aral Sea basin would also benefit the United States. With its withdrawal from Afghanistan, Washington has been courting Uzbekistan as a potential alternative ally and provider of stability in the region. The Uzbek government seems willing to host U.S. military bases and work as a counter-weight to Russia. Kyrgyzstan is also an important regional player. The Manas Air Base, the U.S. military installation near Bishkek, is an important transit point. The country is also working with the United States to battle drug trafficking and infiltration of criminal and insurgent groups. Regional instability could disrupt any of these strategic relationships.

If the past is any indication, the world probably does not need to worry about impending water wars. But they must recognize how tensions over water can easily fuel larger conflicts and distract states from other important geopolitical and domestic priorities. Since formal inter-state institutions are key to alleviating tensions over shared resources, it would be wise, then, for the involved governments as well as the international community to negotiate sufficiently robust agreements to deal with impending environmental change. Otherwise, freshwater will only further frustrate stability efforts in the world's volatile regions.

SHLOMI DINAR is associate professor in the Department of Politics and International Relations and associate director of the School of International and Public Affairs at Florida International University. LUCIA DE STEFANO is associate professor at Complutense University of Madrid and researcher at the Water Observatory of the Botín Foundation. JAMES DUNCAN is consultant on natural resource governance and geography with the World Bank. KERSTIN STAHL is senior scientist at the Institute of Hydrology in the University of Freiburg. KENNETH M. STRZEPEK is research scientist with the Massachusetts Institute of Technology Joint Program on the Science and Policy of Global Change. AARON T. WOLF is a professor of geography in the College of Earth, Ocean, and Atmospheric Sciences at Oregon State University.