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Introduction
Of all the uncertainties climate change presents, its impact on the production and distribution of food is one of the greatest. We are already feeling the effects: 2012 was a bad year for farmers, with droughts and erratic weather decimating crops and pushing up global food prices. Food prices are at historic highs and there have been two global food crises in the last five years leading to riots in Haiti in 2008 and contributing to the Arab Spring in 2011.

Molly D. Anderson and John Reilly examine the complex challenges and trade-offs humanity faces in a world where climate change is upending traditional assumptions about where and how we can produce enough food for the world’s rapidly growing population.

Molly D. Anderson is a professor at College of the Atlantic and holds the Patrtridge Chair in Food and Sustainable Agriculture Systems.
 
Until just a few years ago, there were some blithe assumptions about how climate change would affect food security: Like migrating birds, agriculture will simply move north to escape extreme heat, and only food production will be affected by climate change.
 
Today we recognize that it’s not just temperature, but a whole set of complex interrelated factors — temperature, rainfall, timing, soils, practices throughout the food system and more — that are affected by climate change.
 
Each crop has its own ideal set of circumstances. Having too many warm nights can be deadly for some crops. Not having enough hours of nighttime freeze can hurt others. Human societies have evolved with agriculture over the last 10,000 years to use particular crops in particular places. Now we’re experimenting with drastic changes in a matter of decades.
 
It’s not going to be easy, for a number of reasons, for agriculture to just move north. Farming is one of the most place-based occupations in the world. Farmers won’t easily pick up and move north. If they do, the soil they’ll find will be completely different.
 
Climate change isn’t just affecting the production of food; it’s also affecting consumption of and access to food. Ocean acidification will lower fish catches, which in turn will increase demands on land-based foods. Climate refugees will need new access to food, yet will be unable to produce their own. Food safety will become more challenging.
 
Food security, as defined by the Food and Agriculture Organization of the UN (FAO), is “when all people, at all times, have physical, social and economic access to sufficient, safe and nutritious food that meets their dietary needs and food preferences for an active and healthy life.”
 
Even without climate change, with the growing world population, food security will present a challenge. We need to look for win/win solutions — ones that improve food security and sustainability of food systems on the one hand and that mitigate and adapt to climate change on the other.
 
On the farm level, this means promoting the use of renewable energy in food production, restoring degraded soils and diversifying crops.
 
On a state and regional level, it means first recognizing food as a basic human right and then making policy decisions that flow from that recognition. For example, using land to produce food would take priority over using land to produce biofuels or animal feed; and states and regions would establish adequate food reserves and be able to set their own food and trade policies. States and regions must promote energy and water efficiency throughout the food system as well.
 
Globally, we need to slow population growth. One of the most effective ways to do that is to educate girls and women and provide access to contraceptives. We also need to reduce food waste and over-consumption, particularly by wealthy people and nations of the world.
 
When it comes to food security, the developed world is answering the wrong questions. We’ve focused on increasing availability of food and “feeding the world” (to the benefit of our own corporations). We need to focus on improving food access, reducing our own over-consumption, and addressing why poor people can’t feed themselves in a world with more than enough food for all its inhabitants.
 
John Reilly is senior lecturer and co-director of the Joint Program on the Science and Policy of Global Change and a senior lecturer at the MIT Sloan School of Management.
 
Since 1980, the world’s breadbaskets — areas where major crops like maize, wheat, rice, and soy beans are grown — have warmed significantly. Interestingly, the U.S. is the major exception to this global trend. Our agricultural regions have actually experienced somewhat cooler temperatures overall — with a few exceptions.
 
The effects of climate change on agriculture are likely to be mixed, benefiting crops in some areas and harming crops in others. In colder regions, like New England and much of Canada, growing seasons are becoming longer. We can expect lower crop yields in regions where heat exceeds critical thresholds.
 
Just as agriculture is a major cause of greenhouse gas emissions, it could also play a major role in mitigating climate change.
Scientists estimate that doubling CO2 concentrations from pre-industrial levels would increase crop yields by as much as 20 to 30 percent, but would also increase the growth of weeds. Furthermore, the increase in crop yields from the effects of more carbon dioxide in the air would largely be offset by the effects of increased temperatures and decreased soil moisture.
 
Agriculture and climate are both highly complex pieces of the Earth’s ecosystem. Constructing reasonably accurate, useful models of how the two interact is an enormous scientific challenge.
 
My colleagues at MIT and I have begun developing a model for predicting crop yield changes in the world’s breadbasket regions. We’ve found wide variations in how yields are likely to be affected by climate change. Generally speaking, whether we looked at maize (corn) in North America and West Africa, wheat in Europe and Asia, or soybeans in South America, the results were the same: Areas closer to the equator saw declining yields, some up to 50 percent, while areas closer to the North and South Poles showed increased yields. They balance out at some level, but this kind of change would cause lots of dislocation.
 
With global population projected to peak at 10 billion sometime after 2050, and with rising incomes allowing more people to eat a resource-intensive diet (i.e. eating more meat), we face great agricultural challenges even without the dislocation and disruption climate change will cause.
 
Just as agriculture is a major cause of greenhouse gas emissions, it could also play a major role in mitigating climate change. Our studies show that an aggressive global reforestation policy could result in a half-degree Celsius of avoided warming by 2100. The key would be putting a price on carbon for removing carbon dioxide from the atmosphere. This price would create an incentive for landholders to reforest their land, because forests are great absorbers of carbon.
 
Reforestation comes at a cost. More land for forests means less land for agriculture. That means we could expect to see higher food prices, especially for livestock.
 
This is part of the trilemma of what to do with land in the 21st century. Do we use it to produce biofuels as a substitute for fossil fuels? Do we use it to produce food? Do we use it to preserve biodiversity and store carbon?
 
There are unavoidable trade-offs no matter what we decide. There are no easy solutions when it comes to climate change and food security. What is clear is that the worst “solution” would be continued inaction in the face of the overwhelming evidence that climate change has real and growing effects.

 

First workshop convened high-ranking Chinese environmental officials and experts from top government, university and research offices.


The MIT-Tsinghua China Energy and Climate Project held a workshop on Tuesday March 12 to kick off a landmark study on the impact of China’s vehicle emissions and fuel standards on energy, economic, emissions, air quality and health. The study is being supported by a grant from the Energy Foundation, which provides resources to institutions that most effectively leverage change in transitioning to a sustainable energy future. The workshop, held at Tsinghua University, was hosted by collaborators at the university’s Institute for Energy, Environment, and Economy.

“Understanding the role fuel quality standards could play in cutting China’s emissions and air pollution is crucial to the health of the communities, as well as to addressing growing urban sustainability challenges,” says Valerie Karplus, director of the MIT-Tsinghua China Project and a co-researcher for the study. “This study will provide that insight. We’re grateful to have the support of the Energy Foundation, as well as feedback from a varied stakeholder base.”

The researchers will perform a comparison of policy options for reducing transportation emissions in China. This process will begin with an analysis of China’s transport sector and an updated inventory of emissions by sector. Researchers will also identify regional air quality impacts using a regional chemical transport model and analyze the impact of various policy options on energy use, emissions, the economy and human health.

“This study will be the first to use of an integrated model – simulating travel demand, fuel use, vehicles emissions and air quality – to determine health and economic impacts of fuel policies in China,” Eri Saikawa, a professor at Emory University and the lead researcher for the study, said. “The model will be a powerful tool for assessing transport policy options currently under discussion in China.”

Throughout the project, researchers will communicate their results to policymakers through an ongoing and interactive process. The March 12^th workshop was the first of several of these meetings. It brought together stakeholders from China’s Ministry of Environmental Protection and the Beijing Environmental Protection Bureau, as well as experts from Tsinghua University, Beijing University, Nanjing University, Clean Air Initiative-Asia, the International Council on Clean Transportation, the Energy Foundation, and the Health Effects Institute.

At the March 12^th meeting, the stakeholders provided input on which policy questions would be of greatest interest for the study to consider and explored how the results of the study might be used within their organizations. It was decided that the research would focus on assessing the impacts of fuel quality standards and tailpipe emissions standards in China, with a focus on the potential benefits of implementing the China 6 standard, which is the toughest standard announced so far and targets deeper reductions in nitrous oxide emissions country-wide before 2020.

On Tuesday, four Democrats in Congress unveiled a brand-new proposal for a carbon tax. The set-up is simple: The U.S. government would slap a fee on fossil-fuel emissions and refund the revenue back to the public.

But there’s a twist: The precise details of the carbon tax have yet to be thrashed out. The four lawmakers are soliciting public comments for how big the tax should be and how best to rebate the money.

The proposal is being put forward by Reps. Henry Waxman and Earl Blumenauer, as well as Sens. Sheldon Whitehouse and Brian Schatz.

Here are the key questions they’re wrestling with:

1. What is the appropriate price per ton for polluters to pay? The draft contains alternative prices of $15, $25 and $35 per ton for discussion purposes.

2. How much should the price per ton increase on an annual basis? The draft contains a range of increases from 2 percent to 8 percent per year for discussion purposes.

3. What are the best ways to return the revenue to the American people? The discussion draft proposes putting the revenue toward the following goals, and solicits comments on how to best accomplish each: (1) mitigating energy costs for consumers, especially low-income consumers; (2) reducing the Federal deficit; (3) protecting jobs of workers at trade-vulnerable, energy intensive industries; (4) reducing the tax liability for individuals and businesses; and (5) investing in other activities to reduce carbon pollution and its effects.

4. How should the carbon fee program interact with state programs that address carbon pollution?

Those are, indeed, difficult questions. So let’s take a look at each of them in turn:

1) How big should the carbon tax be? Economists have long argued that a carbon tax can be an elegant way to tackle climate change. If you tax oil, coal, and natural gas and make them more expensive, then people and companies will either use fewer fossil fuels or seek alternatives. Markets will adjust to the new price.

But there’s plenty of dispute over what the appropriate price on carbon emissions should be. For that, you need to figure out how much damage heat-trapping greenhouse gases are actually causing — and figure out how highly to value future generations. The federal government currently pegs the “social cost of carbon” at $21 per ton. Other economists have concluded that the price should be up to 12 times as much.

2) How quickly does the tax need to rise to curtail emissions? A tax that rises each year should, in theory, drive down emissions. But a lot could depend on how quickly the tax actually rises.

Here’s one example: Sebastian Rausch and John M. Reilly of the MIT Global Change Institute recently put forward a proposal for a $20-per-ton carbon tax that would rise 4 percent each year, starting in 2013. (The funds would be used to offset taxes elsewhere.) Here’s what their model predicts would happen to U.S. greenhouse-gas emissions:

Under this proposal, U.S. greenhouse gas emissions do start declining quite a bit (this is the green line), with a relatively small impact on the U.S. economy. But by 2030, emission levels stall, even though the carbon tax keeps rising by 4 percent each year. The United States wouldn’t get anywhere near the 80 percent cut by 2050 that the White House has envisioned.

It’s possible the MIT model is too pessimistic or wrong. It’s also possible that deeper emissions cuts might require a carbon tax that rises even more sharply. But a higher tax could also prove more costly to the economy unless it’s offset properly. So there’s a delicate trade-off here.

3) What’s the best way to use the carbon tax revenue? A carbon fee usually gets criticized for hurting poorer Americans the most—they spend the biggest slice of their income on gasoline and other energy-intensive products, after all. But Rausch and Reilly found that a lot of the distributional effects depend on how Congress rebates the revenue, as shown in the chart below:

The green line shows how different income groups would be affected in 2015 if the carbon tax was used to fend off cuts to social welfare programs like Medicaid. Lower-income Americans would benefit significantly, while wealthier Americans would take a small hit.

By contrast, the red and blue lines show the effects if revenue from the carbon tax was used to cut the corporate tax or personal income tax—in those cases, higher-income Americans would come out ahead.

If, however, carbon tax revenue was used to cut payroll taxes—that’s the black line—then the welfare effects in 2015 are more or less neutral.

On the flip side, some experts like Mark Muro of Brookings have argued that a portion of the revenue raised by a carbon tax should be used to fund public clean-energy R&D. The country won’t wean itself off oil solely because carbon gets taxed. We’ll also need public-transit alternatives, or electric-vehicle infrastructure, or futuristic new hydrogen cars. And in many cases, Muro argues, the government may have to help bankroll this infrastructure.

4) How does the carbon tax interact with the states? California is currently operating its own comprehensive program to cut greenhouse-gas emissions 80 percent by 2050. And 10 states in the Northeast have a small cap-and-trade program for electric utilities. Should these states somehow get “credit” for moving early on global warming? And what’s the best way to do that under a carbon-tax system?

In any case, these are all difficult questions. Those who want to join in on this debate can submit comments to the lawmakers at cutcarbon@mail.house.gov. The comment period ends April 21.

Moniz is the Cecil and Ida Green Professor of Physics and Engineering Systems, as well as the director of the MIT Energy Initiative (MITEI) and the Laboratory for Energy and the Environment. 

By Brad Plumer
February 22, 2013

What’s the best way to curtail gasoline consumption? Economists tend to agree on the answer here: Higher gas taxes at the pump are more effective than stricter fuel-economy standards for cars and trucks.

Much more effective, in fact. A new paper from researchers at MIT’s Global Change program finds that higher gas taxes are “at least six to fourteen times” more cost-effective than stricter fuel-economy standards at reducing gasoline consumption.

Why is that? One of the study’s co-authors, Valerie Karplus, offers a basic breakdown here: Fuel-economy standards work slowly, as manufacturers start selling more efficient vehicles, and people retire their older cars and trucks. That turnover takes time. By contrast, a higher gas tax kicks in immediately, giving people incentives to drive less, carpool more, and buy more fuel-efficient vehicles as soon as possible.

A great deal also depends on whether biofuels and other alternative fuels are available. A tax on gasoline makes these alternative fuels more competitive, whereas fuel-economy standards don’t. “We see the steepest jump in economic cost between efficiency standards and the gasoline tax if we assume low-cost biofuels are available,” Karplus said in an MIT press release.

And yet… all this economic research never seems to have any effect on lawmakers. Since 2007, Congress and the Obama administration have moved to increase federal fuel economy standards, now scheduled to rise to 54.5 miles per gallon by 2025. According to the MIT estimates, this will cost the economy six times as much as simply raising the federal gas tax from its current level of 18.4 cents per gallon to 45 cents per gallon. Yet no one in Congress has even proposed the latter option.

One explanation is that the public just prefers things this way. Higher fuel-economy standards do impose costs, but they’re largely “hidden” costs — in the form of pricier vehicles in the showroom. A higher gas tax, by contrast, is visible every time people fill up at the pump.

In fact, a recent NBER paper by MIT’s Christopher Knittel found that this has been the case for decades. Between 1972 and 1980 the price of oil soared 650 percent. There was endless public debate during this period about how best to reduce reliance on fossil fuels. And, as Knittel discovered, the public consistently preferred price controls and fuel-economy standards over higher gas taxes. That was true no matter how often people were informed that gas taxes were the superior option.

“Given the saliency of rationing and vehicle taxes,” Knittel concluded, “it seems difficult to argue that these alternative polices were adopted because they hide their true costs.” In other words, the public seems to have an (expensive) preference for inefficient regulations over higher taxes to curb gasoline. Economists find it maddening, but it’s hard to change.

Further reading:

–On the other hand, if you want to see a rare economic argument for fuel-economy standards, check out this 2006 paper (pdf) by Christopher Knittel. He found that Americans were becoming less sensitive to fuel prices over time — which strengthened the case for policies like CAFE standards.

THE average price of gasoline in the United States, $3.78 on Thursday, has been steadily climbing for more than a month and is approaching the three previous post-recession peaks, in May 2011 and in April and September of last year.

But if our goal is to get Americans to drive less and use more fuel-efficient vehicles, and to reduce air pollution and the emission of greenhouse gases, gas prices need to be even higher. The current federal gasoline tax, 18.4 cents a gallon, has been essentially stable since 1993; in inflation-adjusted terms, it’s fallen by 40 percent since then.

Politicians of both parties understandably fear that raising the gas tax would enrage voters. It certainly wouldn’t make lives easier for struggling families. But the gasoline tax is a tool of energy and transportation policy, not social policy, like the minimum wage.

Instead of penalizing gasoline use, however, the Obama administration chose a familiar and politically easier path: raising fuel-efficiency standards for cars and light trucks. The White House said last year that the gas savings would be comparable to lowering the price of gasoline by $1 a gallon by 2025. But it will have no effect on the 230 million passenger vehicles now on the road.

Greater efficiency packs less of a psychological punch because consumers pay more only when they buy a new car. In contrast, motorists are reminded regularly of the price at the pump. But the new fuel-efficiency standards are far less efficient than raising gasoline prices.

In a paper published online this week in the journal Energy Economics, I and other scientists at the Massachusetts Institute of Technology estimate that the new standards will cost the economy on the whole — for the same reduction in gas use — at least six times more than a federal gas tax of roughly 45 cents per dollar of gasoline. That is because a gas tax provides immediate, direct incentives for drivers to reduce gasoline use, while the efficiency standards must squeeze the reduction out of new vehicles only. The new standards also encourage more driving, not less.

Other industrialized democracies have accepted much higher gas taxes as a price for roads and bridges and now depend on the revenue. In fact, Germany’s gas tax is 18 times higher than the United States’ (and seven times more if the average state gas tax is included). The federal gasoline tax contributed about $25 billion in revenues in 2009.

Raising the tax has generally succeeded only when it was sold as a way to lower the deficit or improve infrastructure or both. A 1-cent federal gasoline tax was created in 1932, during the Depression. In 1983, President Ronald Reagan raised the tax to 9 cents from 4 cents, calling it a “user fee” to finance transportation improvements. The tax rose again, to 14.1 cents in 1990, and to 18.4 cents in 1993, as part of deficit-reduction deals under President George Bush and President Bill Clinton.

A higher gas tax would help fix crumbling highways while also generating money that could help offset the impact on low- and middle-income families. Increasing the tax, as part of a bipartisan budget deal, with a clear explanation to the public of its role in lowering oil imports and improving our air and highways, could be among the most important energy decisions we make.

Valerie J. Karplus is a research scientist in the Joint Program on the Science and Policy of Global Change at M.I.T.

Read more about the study here. 

Related: Carbon Tax a 'Win-Win-Win' for America's Future

 

MIT researchers find vehicle efficiency standards are at least six times more costly than a tax on fuel.

IN CASE YOU MISSED IT: Valerie Karplus makes her case in an op-ed in the NY Times here. 

Vehicle efficiency standards have long been considered vital to cutting the United States’ oil imports. Strengthened last year with the added hope of reducing greenhouse gas emissions, the standards have been advanced as a way to cut vehicle emissions in half and save consumers more than $1.7 trillion at the pump. But researchers at MIT find that, compared to a gasoline tax, vehicle efficiency standards come with a steep price tag.

“Tighter vehicle efficiency standards through 2025 were seen as an important political victory. However, the standards are a clear example of how economic considerations are at odds with political considerations,” says Valerie Karplus, the lead author of the study and a researcher with the MIT Joint Program on the Science and Policy of Global Change. “If policymakers had made their decision based on the broader costs to the economy, they would have gone with the option that was least expensive – and that’s the gasoline tax.”

The study, published this week in the March edition of the journal Energy Economics, compares vehicle efficiency standards to a tax on fuel as a tool for reducing gasoline use in vehicles. The researchers found that regardless of how quickly vehicle efficiency standards are introduced, and whether or not biofuels are available, the efficiency standards are at least six times more expensive than a gasoline tax as a way to achieve a cumulative reduction in gasoline use of 20 percent through 2050. That’s because a gasoline tax provides immediate, direct incentives for reducing gasoline use, both by driving less and investing in more efficient vehicles. Perhaps a central reason why politics has trumped economic reasoning, Karplus says, is the visibility of the 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,” Karplus says. “With a vehicle efficiency standard, your costs won't increase unless you buy a new car, and even better than that, policymakers will tell you you’re actually saving money. As my colleague likes to say, you may see more money in your front pocket, but you’re actually financing the policy out of your back pocket through your tax dollars and at the point of your vehicle purchase.”

Along with being more costly, Karplus and her colleagues find that it takes longer to reduce emissions under the vehicle efficiency standards. That’s because, with more efficient vehicles, it costs less to drive, so Americans tend to drive more. Meanwhile, the standards have no direct impact on fuel used in the 230 million vehicles currently on the road. Karplus also points out that how quickly the standards are phased in can make a big difference. The sooner efficient vehicles are introduced into the fleet, the sooner fuel use decreases and the larger the cumulative decrease would be over the period considered, but the timing of the standards will also affect their cost.

The researchers also find that the effectiveness of the efficiency standards depends in part on the availability of other clean-energy technologies, such as biofuels, that offer an alternative to gasoline.

“We see the steepest jump in economic cost between efficiency standards and the gasoline tax if we assume low-cost biofuels are available,” Karplus says. “In this case, if biofuels are available, a lower gasoline tax is needed to displace the same level of fuel use over the 2010 to 2050 time frame, as biofuels provide a cost-effective way to displace gasoline above a certain price point. As a result, a lower gas tax is needed to achieve the 20 percent cumulative reduction.”

To project the impact of vehicle efficiency standards, Karplus and her colleagues improved the MIT Emissions Predictions and Policy Analysis Model that is used to help understand how different scenarios to constrain energy affect our environment and economy. For example, they represent in the model alternatives to the internal combustion engine based on the expected availability and cost of alternative fuels and technologies, as well as the dynamics of sales and scrappage that affect the composition of the vehicle fleet. Their improvements to the model were recently published in the January 2013 issue of the journal Economic Modelling.

Related: Carbon Tax a 'Win-Win-Win' for America's Future