News and Outreach: Valerie Karplus

The latest Obama-Xi announcement sends a strong message: the two nations are acting fast to enable a global low carbon transition. Friday’s joint announcement is an unprecedented step by the world’s #1 and #2 emitters to commit, at the highest levels, to a strong set of domestic policies and to reinforce global mechanisms that will help to engage peers ahead of the upcoming landmark climate change negotiations in Paris. 

Pricing Carbon

Xi has committed China to launching a national emissions trading system for CO2 in 2017. An emissions trading system will directly constrain a large share of China’s CO2 emissions and, by putting a price on emissions, encourage reductions where they cost least. This is impressive in that China is pledging to reduce emissions at a time when its per-capita income is less than one-fifth of the U.S. and its economy faces headwinds. It recognizes the long-term benefits of action now—for local air quality, global climate, and its own long-term leadership in delivering innovative solutions that all nations will eventually need.

While China is not the first to establish an emissions trading system, China’s is likely to be the largest when it comes online in 2017. While the European Union has built an emissions trading system over the past two decades, the U.S. has so far not been successful in adopting a national system for greenhouse gases. In 2009 the Waxman-Markey Bill, which would have established an emissions trading system in the U.S., failed to pass Congress, leaving the U.S. to rely on a piecemeal approach that largely repurposed existing regulations, such as vehicle fuel economy standards and power plant emissions limits established under the Clean Air Act, to mandate CO2 emissions reduction. Indeed, these measures formed the cornerstone of the U.S. domestic action pledged on Friday, and they will have impact. However, an emissions trading system that could deliver the same reductions at lower aggregate cost has so far proven politically unpalatable. China’s latest move could prompt a rethink on emissions trading in the U.S.

Linking Global and Local Action

Along with a strong portfolio of coordinated domestic actions, Xi and Obama made progress on defining the architecture of a global climate agreement. The two leaders have agreed on the need for an enhanced system that monitors domestic action through reporting and review of progress, recognizing that some developing nations will still need time to put these capacities into place. Both sides also recognized the need to increase ambition over time. This is essential because even with all present contributions, the global emissions trajectory is not expected to bend down anytime soon. Recognizing that this will likely not be fully resolved in Paris, setting in place a timeline for assessing and revisiting commitments going forward will go a long way towards ensuring that the goal Xi and Obama reaffirmed at the outset of their remarks—deep reductions in GHG emissions that will markedly limit global temperature rise—does not slip off the radar.

Beyond generating momentum ahead of Paris, U.S.-China joint action will have far-reaching consequences at home when it comes to enabling a low carbon transition. Although many insiders anticipated that an emissions trading system in China would be established, efforts to codify this effort in a new Climate Change Law were moving more slowly—this high-level pledge will redouble the pressure. Beyond emissions trading, China has also pledged to promote “green dispatch” in the electricity sector, which will prioritize lower emitting plants. In China, generators are powerful interests entitled to supply a “fair share” of annual generation—now, their “fair share” will need to reflect environmental impact more strongly and directly.

Leading on Climate and Development

Perhaps the greatest promise of the latest announcement by China and the U.S. lies in its invitation to all parties to increase ambition, if not before Paris then as soon as possible as part of ongoing negotiations. On the eve of Paris, the world is poised to miss the 2 degree target—by a large margin. Stronger action will be needed by developed and developing countries alike. By committing to limit CO2 emissions, China has shown that domestic action on climate change does not need to undermine long-term development goals. In recent years, it has developed the domestic capability to assess—through research, modeling, and real-world experimentation—the advantages and disadvantages of various instruments for limiting fossil energy use and CO2 emissions. The results suggest that some opportunities, such as industrial energy efficiency and new energy development, can support cleaner air, better operational performance, and—in the case of, say, solar energy—open opportunities as a leading global provider of clean technology. Every developing country will have its unique set of opportunities. The architecture emerging on the road to Paris is shaping up in a way that will accommodate these differences, allowing the countries that are poised to grow the fastest over the next several decades to find ways to power this growth with clean, affordable, low carbon energy sources. Greater action from the developed world will also be essential. Ideally, the steps Xi and Obama have taken last week will inspire a broad-based, cooperative effort to deliver more than promised that carries both local and global benefits.

Dr. Valerie Karplus is a ChinaFAQs Expert at the Massachusetts Institute of Technology (MIT). She is an Assistant Professor in the Global Economics and Management Group at the MIT Sloan School of Management and Director of the China Energy and Climate Project (CECP) at MIT.

ChinaFAQs is a project facilitated by the World Resources Institute that provides insight into critical questions about Chinese policy and action on energy and climate change. The ChinaFAQs network is comprised of U.S.-based experts, including researchers at U.S. universities and government laboratories, independent scholars, and other professionals.

Photo Credit: U.S. Embassy the Hague via Flickr Creative Commons License

On the eve of President Xi's visit to the US and summit with President Obama, Professor Karplus participated in the panel discussion on Meeting China’s Climate Goals at Columbia University today, September 21, 2015, at 12:30-2:00 p.m. David Sandalow, Inaugural Fellow, Center on Global Energy Policy, and former senior official at the White House, State Department, and U.S. Department of Energy moderated the discussion among the expert speakers who include Valerie Karplus, Assistant Professor of Global Economics and Management, MIT Sloan School, and Director of the Tsinghua-MIT China Energy and Climate Project; Zhu Liu, Fellow, Resnick Sustainability Institute, California Institute of Technology and Associate, Kennedy School, Harvard University; and Kelly Sims Gallagher, Professor of Energy and Environmental Policy, the Fletcher School, Tufts University, and former Senior Policy Advisor, Office of Science and Technology Policy, the White House.
 
A podcast of this event will be available three-five days after the date of the event through iTunes or via the Center on Columbia Global Energy Policy’s website.

By Nancy W. Stauffer, MIT Energy Initiative

Overview

Researchers from MIT and Tsinghua University in Beijing are collaborating to bring new insights into how China—now the world’s largest emitter of carbon dioxide (CO₂)—can reverse the rising trajectory of its CO₂ emissions within two decades. They use a newly developed global energy-economic model that separately represents details of China’s energy system, industrial activity, and trade flows. In a recent study, the team estimated the impact on future energy use, CO₂ emissions, and economic activity of new policies announced in China, including a price on carbon, taxes on fossil fuel resources, and nuclear and renewable energy deployment goals. The researchers conclude that by designing and implementing aggressive long-term measures now, Chinese policy makers will put the nation on a path to achieve recently pledged emissions reductions with relatively modest impacts on economic growth.

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Valerie Karplus of the MIT Sloan School of Management (left) and Xiliang Zhang of Tsinghua University pose on the Tsinghua campus. In their joint research, they are using a novel model to investigate the impacts of Chinese energy and climate policies on the country’s future energy use, carbon dioxide emissions, and economic activity. Photo courtesy of the Tsinghua-MIT China Energy and Climate Project

In November 2014, the presidents of the United States and China delivered a joint announcement committing their countries to new, aggressive measures to curb carbon emissions. Those pledges were seen as a breakthrough in global climate change negotiations. Until recently, binding commitments were in place only for a group of developed nations together responsible for about 15% of global carbon emissions. The new action involves a developed nation and a developing nation that together represent 45% of all emissions today. Moreover, it breaks a longstanding stalemate between the United States and China in which each has been waiting for the other to act first, and it sets the stage for other developing nations to declare their commitments to the global effort.

China’s pledge represents an ambitious target for a rapidly growing country. The country pledged to turn around the constant growth in its CO₂ emissions by 2030 at the latest and to increase the fraction of its energy coming from zero-carbon sources to 20% by the same year—approximately double the share it has achieved so far. The commitment raises serious questions: Are those goals realistic, and if so, what new actions will be needed to accomplish them?

“To meet its new 2030 targets, China will need to take aggressive steps, including introducing a nationwide price on carbon emissions as well as preparing for the safe and efficient deployment of nuclear and renewable energy at large scale,” says Valerie J. Karplus, assistant professor of global economics and management at the MIT Sloan School of Management and director of the Tsinghua-MIT China Energy and Climate Project (CECP). “But with strong action, China’s targets are credible and within reach.”

Her assessment is based on studies that she and her CECP colleagues at MIT and Tsinghua University had been performing before the joint pledge was announced. The work was motivated by policy changes that were already occurring within China. In January 2013, an extreme episode of bad air quality and subsequent public outcry led to the adoption the following September of a new air pollution action plan. A few months later, Chinese policy makers at a major government summit pledged to tackle environmental problems by using new market-based instruments, including an emissions trading system that will put a price on CO₂ emissions as well as taxes on fossil fuel resources that will incentivize firms to conserve energy.

“So whether it was for reasons of bad air quality or greater concern about climate change or deeper interest in market reforms, the winds of change were blowing,” says Karplus. “And we thought, ‘Well, we need to model this!’” A theoretical analysis could produce insights into how such policies might affect China’s energy system and carbon emissions, and it could shed light on the level of carbon tax that might be required to achieve a given emissions reduction—information that could help guide Chinese policy makers as they further define the details of their plans.

New model, new analyses

To perform their study, the MIT and Tsinghua collaborators used the China-in-Global Energy Model (C-GEM), which MIT researchers and Tsinghua graduate students developed while the Tsinghua students were visiting MIT three years ago. “In our joint research we use a model that was built with methods largely contributed by MIT but with detailed data and insights largely provided by our Tsinghua colleagues,” says Karplus.

Specifically, the researchers calibrated the model using domestic economic and energy data for China in both 2007 and 2010. And rather than combining all the energy-intensive industries into a single sector, they divided that group into six distinct sectors—both within China and within the 18 additional regions that represent the rest of the world in the model. That disaggregation is important for two reasons, says Karplus: Those six sectors differ in energy intensity and growth trends, and in China—unlike in many developed economies—they make up a significant share of economic activity and account for a large share of emissions. Finally, the researchers incorporated into the model changes in China’s economic structure that may occur as per capita income increases over time. In particular, the main driver of economic growth gradually shifts away from investment (for example, in infrastructure development) and toward consumption.

In their analysis of China’s policy initiatives, they assume two scenarios with differing levels of policy effort, plus one more scenario that assumes that no energy or climate policies are in place after 2010—an approach that is generally viewed as unsustainable but here serves as a baseline for comparison. The detailed assumptions for each scenario appear in the table below.

The Continued Effort (CE) scenario assumes that China remains on the path of reducing CO₂ intensity (carbon emissions per dollar of GDP) by about 3% per year through 2050, consistent with an extension of commitments the country made at global climate talks in 2009. Importantly, the researchers find that a carbon price is needed to achieve such a reduction in carbon intensity; the needed improvements in energy efficiency and emissions do not result from normal equipment turnover and upgrading, as they have in the past. The CE scenario also assumes the extension of existing measures including resource taxes on crude oil, natural gas, and coal; a “feed-in tariff” that guarantees returns to renewable electricity generators; and increased deployment of hydroelectricity and of nuclear electricity (here assumed to be mandated by government).

The Accelerated Effort (AE) scenario is designed to achieve a more aggressive CO₂ reduction—4% per year—and includes a carbon price consistent with that target. It assumes the same feed-in tariff as under the CE scenario, but now the assumed cost of integrating intermittent renewables is lower. It also assumes higher resource taxes on fossil fuels and greater deployment of nuclear electricity beyond 2020.

Impact on energy demand and emissions

The first figure below shows total energy demand over time for the three scenarios, plus the actual breakdown of primary energy use by source in 2010 and estimates thereafter from the AE scenario only. The second figure shows total CO₂ emissions between 2010 and 2050 for each of those scenarios.

With no energy or climate policies in effect (the “No Policy” scenario), total CO₂ emissions continue to rise through 2050, with no peak in sight. Rising emissions are mainly due to continued reliance on China’s domestic coal resources. In 2050, more than 66% of all energy comes from coal—more than 2.8 times the current level, which is already widely viewed as untenable within China.

In the CE scenario, total energy use is well below the No Policy case, and that decline generates disproportionately high reductions in emissions. Carbon emissions level off at about 12 billion metric tons (bmt) in the 2030 to 2040 time frame. The CO₂ charge needed to achieve that outcome reaches $26/ton CO₂ in 2030 and $58/ton CO₂ in 2050. Deployment of non-fossil energy is significant, and its share of total energy demand climbs from 15% in 2020 to about 26% through 2050. Nuclear power expands significantly to 11% of total primary energy in 2050. Coal continues to account for a significant share of primary energy demand (39% in 2050). The share of natural gas use nearly doubles between 2030 and 2050, while the share of oil use increases slightly over the same period.

Under the AE scenario, CO₂ emissions level off in the 2025 to 2035 time frame, peaking at about 10 bmt—about 20% above current emissions levels. The carbon price rises from $38/ton CO₂ in 2030 to $115/ton CO₂ in 2050. Those prices are substantially above the levels in the CE scenario, but CO₂ emissions now peak as much as a decade earlier.

Demand for energy in the three scenarios. This figure shows total energy demand in the No Policy, Continued Effort, and Accelerated Effort scenarios, with the primary energy mix shown for the Accelerated Effort scenario only. Both levels of policy effort significantly decrease total energy demand relative to the baseline No Policy scenario, which assumes that no energy or climate policies are in effect after 2010.

 

Total CO₂ emissions in China in the three scenarios. The decreases in energy demand in the Continued Effort and Accelerated Effort scenarios (shown in top figure) bring about even greater reductions in CO₂ emissions. While the Accelerated Effort scenario involves more aggressive measures than the Continued Effort scenario does, it causes CO₂ emissions to peak about a decade earlier and brings more substantial decreases thereafter.

Under the AE scenario, non-fossil energy accounts for fully 39% of the primary energy mix by 2050. Wind, solar, and biomass electricity continue to increase through 2050 (as they do in the CE scenario), and nuclear is now 16% of the total energy mix. Despite its relatively low carbon content, natural gas is eventually penalized by the increasing carbon price. Between 2045 and 2050, natural gas actually starts to decline as a share in absolute terms. Coal’s share drops dramatically—from 70% in 2010 to about 28% by 2050, with peak use occurring in about 2020. In contrast, oil’s share of energy use continues to increase through 2050.

The differing outcomes for coal and oil are largely due to the availability and cost of substitutes. Coal is the least expensive fuel to displace; it has many substitutes, including wind, solar, nuclear, and hydro in the power sector and natural gas and biomass in industrial processes. In contrast, fewer substitutes are available for oil-based liquid fuels used in transportation; and switching to the alternatives—for example, biobased fuels or electric vehicles—is a relatively expensive way to reduce CO₂ emissions. “As a result, oil consumption is relatively insensitive to a carbon price,” says Karplus. “So China seems set to account for a significant share of global oil demand over the period being considered.”

Relevance for the new Chinese pledge

The findings of the Tsinghua-MIT analysis have direct relevance for current policy making in China. Under the new bilateral agreement with the United States, China needs to start reducing emissions at or before the year 2030. In the AE scenario, the researchers find that by starting now, China should be able to meet that 2030 target at an added cost to the economy that rises to just 2.6% of China’s domestic consumption by 2050—a relatively modest impact on the country’s economic development. “While we are currently working on detailed calculations, we expect that the economic cost will be offset—at least to some extent—by associated reductions in the environmental and health costs of China’s coal-intensive energy system,” says Karplus.

The CECP researchers are continuing to study how different energy and climate policies in China could be used to support the achievement of the China-US agreement. For example, they are looking at the carbon trading system now being tested in several regions of China, in particular, examining which provinces win or lose under the carbon price and how policy design choices can mitigate uneven impacts. And they’re investigating how a carbon price affects air pollution and how air pollution policies affect carbon emissions.

Karplus stresses that their work is not meant to be a crystal ball that tells the future. “It’s really intended to develop our collective intuition of the level of effort required to change China’s energy system,” she says. “And because the CECP involves both Chinese and US contributors, we are in a position to offer analyses and outputs that we hope will be trusted and valued by policy makers in both countries as they work to strengthen the bilateral relationship.”

Already Chinese policy makers are benefiting from the CECP, according to Professor Xiliang Zhang, CECP lead and director of the Institute of Energy, Environment, and Economy at Tsinghua University. He says, “The work of the CECP has played an important role in helping policy makers in China understand the challenges and opportunities that will accompany the country’s low-carbon energy transformation.”

This research is supported by Eni S.p.A., the French Development Agency (AFD), ICF International, and Shell International Limited, founding sponsors of the MIT-Tsinghua China Energy and Climate Project (CECP). (Eni S.p.A. and Shell are also Founding Members of the MIT Energy Initiative.) The Energy Information Agency of the US Department of Energy and the Energy Foundation also supported this work as sustaining sponsors. Additional support came from the National Science Foundation of China, the Ministry of Science and Technology of China, the National Social Science Foundation of China, and Rio Tinto China, and from the MIT Joint Program on the Science and Policy of Global Change through a consortium of industrial sponsors and US federal grants. Further information can be found in:

X. Zhang, V.J. Karplus, T. Qi, D. Zhang, and J. He. Carbon Emissions in China: How Far Can New Efforts Bend the Curve? MIT Joint Program on the Science and Policy of Global Change Report No. 267, October 2014.

	Photo: Christopher Harting

by Jennifer Chu | MIT News Office

Joint Program researchers Prof. Valerie Karplus and Prof. Noelle Selin receive grants from from the Environmental Solutions Initiative to examine how current efforts to reduce coal use in China affect toxic air pollution across Asia.
 
How can sustainable consumption in U.S. cities be fostered? Can the ocean floor be mined in an ecologically benign way? What are the health risks associated with the mining of rare metals used in energy-efficient products like photovoltaic devices? And how can truly promising environmental solutions have a better chance of becoming real economic policies?

These are some of the complex questions that researchers at MIT will now be able to tackle, with support from the MIT Environmental Solutions Initiative (ESI). The initiative was established last May to inspire solutions to major environmental problems through collaborative partnership.

In response to a call for research proposals, the ESI received 59 submissions. In March, the initiative awarded seed grants of up to $200,000 to nine research groups over the next two years.

ESI director Susan Solomon, the Ellen Swallow Richards Professor in MIT’s Department of Earth, Atmospheric and Planetary Sciences, says the seed grants have jumpstarted new collaborations among a variety of disciplines across campus.

“I was really pleased that so many people reached out to colleagues and looked at new collaborations, which was exactly what we were hoping would occur as a result of this process,” Solomon says. “There’s a lot of new thinking here. … I’m really pleased that people began those conversations. I think they’re just going to continue to grow and blossom as this initiative moves forward.”

The nine winning proposals fell into four main themes: sustainability; metals and mining; healthy cities; and climate/risk/mitigation.

Sustainability

According to the Environmental Protection Agency, humans have consumed more material and natural resources in the past 50 years than in the entire previous history of human existence. To curb consumption, the environmental community has encouraged the practice of sustainable consumption, using the mantra: “Reduce, Reuse, Recycle.”

But how are U.S. cities — hubs of materialism and consumption — actually practicing sustainable consumption? A group of urban planners, architects, and historians led by Judith Layzer, a professor of environmental policy in the Department of Urban Studies and Planning, will carry out a survey of 285 municipalities to explore the degree to which sustainable consumption goals have been adopted by local governments. The group wrote in its proposal that it hopes the survey will serve as a “valuable resource for cities that aspire to move toward sustainable consumption.”

Finding solutions to major environmental problems often involves input from both technology and policy experts — but it can be frustrating for both parties when they find that reasonable solutions can be difficult to put into practice. A classic example is the shared resource, such as a groundwater aquifer, that is overused to the point where it fails to benefit all parties. A group of engineers and economists, led by Dennis McLaughlin, the H.M. King Bhumibol Professor in the Department of Civil and Environmental Engineering, and Parag Pathak, an associate professor of economics, will examine the behaviors that drive competition for natural resources using game theory, a framework that has been used to analyze cooperative behavior in economics.

“There is a gap between the promise of game theory and the continuing difficulty of designing workable policy solutions to environmental issues,” the team wrote in its grant proposal. “The ESI seed grant program gives us a chance to narrow these gaps, so that the environmental solutions we propose as a community have a better chance of being implemented as real policies.”

Metals and mining

Metals and mining products are increasingly used to support development. For example, they are essential to building wind turbines, solar panels, photovoltaic devices, and lithium-ion batteries.

But as societies depend more on rare metals for products, what impact will rising demand have on the environment? A group of engineers, led by Antoine Allanore, the Thomas B. King Assistant Professor in Metallurgy, and Alan Hatton, the Ralph Landau Professor of Chemical Engineering Practice, plans to launch a metals and mining initiative at MIT. As part of the project, the team will organize several symposia on campus that will connect industry stakeholders with MIT researchers to explore issues of sustainable mining.

Rare metals like indium and lanthanide are increasingly mined for use in high-efficiency photovoltaic devices, light-emitting diodes (LEDs), and batteries for hybrid cars. The effects of these metals on the environment and human health are unknown. A team of engineers led by John Essigmann, the William R. and Betsy P. Leitch Professor in the Department of Biological Engineering; Bevin Engelward, a professor of biological engineering; and Harold Hemond, the William E. Leonhard Professor in the Department of Civil and Environmental Engineering, will combine techniques in geochemistry and cell and molecular toxicology to assess the adverse effects of rare metals in the environment, and their potential impact on human health. Such an assessment, the team wrote in its proposal, should occur before new substances are introduced widely in the environment: “History provides numerous cautionary examples of the great economic and societal costs incurred when knowledge lags behind the deployment of new products.”

Deep below the ocean floor, there exist vast resources of gold, copper, platinum, and other rare metals — resources that are increasingly in demand for use in electronics and energy-efficient products. The world’s first deep-sea mining operation, scheduled to commence in 2017, will dig beneath the Bismarck Sea, off Papua New Guinea, for minerals. But scientists are concerned that mining operations may create currents that carry pollutants up from the deep sea, potentially poisoning marine species and the humans that consume them.

A team led by Thomas Peacock and Pierre Lermusiaux, both associate professors of mechanical engineering, and Glenn Flierl, a professor of oceanography, will develop a detailed ocean model to identify key circulation patterns in the region and determine the biological impacts of the mining operations. The team says the modeling tools developed through this effort “can be applied to any proposed location for the growing field of deep-sea mining.”

Healthy cities

China has some of the world’s worst air pollution, as well as half its mercury emissions, due to its rising use of coal. In the last few years, the country has adopted policies to curb coal use and reduce air pollution. It is unclear, however, whether these measures will be consistent with the air-quality improvements set by newer policies.

A team of economists, engineers, and atmospheric chemists led by Valerie Karplus, an assistant professor of global economics and management, and Noelle Selin, the Esther and Harold E. Edgerton Assistant Professor in the Engineering Systems Division and the Department of Earth, Atmospheric and Planetary Sciences, will examine how current efforts to reduce coal use in China affect toxic air pollution across Asia. The team will also estimate changes in coal demand throughout Asia, as China’s own demand for coal falls. The team’s proposal states: “Our systems approach enables us to fully evaluate and identify effective efforts to address regional air quality, taking into account both the complexity of economic interactions and atmospheric chemical behavior.”

Detailed measurements of air quality, particularly in urban environments, will ultimately help to reduce populations’ exposure to air pollutants. In recent years, advances in sensor technology have offered the promise of sensitive, distributed, urban air-quality networks, although few actually exist. A group of urban planners, atmospheric chemists, and civil engineers plans to address the need for air-quality networks, using “big data.” The team plans to examine air-quality measurements around the MIT campus and in Beijing, and apply advanced data-analysis techniques to gain “quantitative insight” into pollution sources.

This project, the team says, “would represent the first application of machine-learning tools to environmental sensors.” The work will be led by Marta Gonzalez, an assistant professor of civil and environmental engineering; Colette Heald, the Mitsui Career Development Associate Professor in Contemporary Technology; Jesse Kroll, an associate professor of civil and environmental engineering, and Jinhua Zhao, the Edward H. and Joyce Linde Professor in the Department of Urban Studies and Planning.

Climate/risk/mitigation

Tropical peatlands, swamp forests found mostly in Southeast Asia, are thought to be vast carbon sinks, containing up to 70 billion tons of carbon — about 3 percent of the world’s soil carbon. Over the last 25 years, peatland forests have been cut and drained so that the underlying peat acts not as a sink, but a source, emitting enormous stores of carbon dioxide and methane into the atmosphere.

Policymakers and researchers suggest that controlling these emissions would be a cost-effective way to reduce the world’s total greenhouse-gas emissions. But there’s little knowledge about the physical and biological processes within peatlands that control carbon and methane fluxes. A group of engineers and atmospheric scientists will study soil processes in Brunei, on the island of Borneo, to characterize the flow of carbon dioxide and methane to the atmosphere. The researchers ultimately hope to apply their results to strategies for controlling greenhouse gas emissions. The group includes Charles Harvey, Benjamin Kocar, and Martin Polz of the Department of Civil and Environmental Engineering and Shuhei Ono and Roger Summons of the Department of Earth, Atmospheric and Planetary Sciences.

While two-thirds of greenhouse-gas-induced warming is due to carbon dioxide, other gases, such as methane and halogen-containing gases, contribute significantly to climate change. In the near future, these emissions may increase as a fraction of total greenhouse-gas emissions, as policies to reduce carbon dioxide bear results. As countries transition from coal to natural gas for electricity, more methane may escape into the atmosphere through leaks in natural-gas pipelines.

A team led by Jessika Trancik, the Atlantic Richfield Career Development Assistant Professor in Energy Studies, and Francis O’Sullivan, director of research and analytics at the MIT Energy Initiative, will develop metrics to compare climate impacts of non-carbon dioxide emissions, such as methane. The researchers will use the metrics to identify ways to reduce these emissions, particularly those of methane through the natural-gas supply chain. The team will use these results to inform current U.S. policy, including a new federal initiative to reduce methane. “Climate change mitigation is a multi-gas problem,” the researchers wrote in their grant proposal. “This work will inform important policy decisions that are slated to be made in the next few years.”

China Energy and Climate Project Director Professor Valerie J. Karplus appeared on Channel NewsAsia to discuss the impacts and broader significance of the Korean emissions trading system kicking off last week. Watch the interview below.


 

by Jesse Jenkins | The Energy Collective

Jesse Jenkins: Even before world leaders descended on Lima, Peru this week for United Nations-sponsored climate negotiations, climate diplomacy made global headlines with the joint announcement of a partnership between the world's two largest carbon emitters: the United States and China.

The joint pledge to cut greenhouse gas emissions and collaborate on clean energy technology development has been hailed as a potential sea change in the tone and substance of international climate mitigation efforts.

To dig in to the details of this U.S.-China climate partnership, I caught up this week with Valerie Karplus, an assistant professor at the Massachusetts Institute of Technology's Sloan School of Management and Director of the Tsinghua-MIT China Energy Program.

An expert on both American and Chinese energy and climate policy, Prof. Karplus and I explored what the climate deal means for domestic energy policy in each nation, chatted about the major drivers of emissions growth in China, and considered implications of the new emissions pledges for international climate negotiations.

Read the full interview at the Energy Collective

By Mike Orcutt | MIT Technology Review

China may put a stop to growing carbon dioxide emissions earlier than expected, but how quickly they start coming down is also important.

In an agreement announced last week, China and the United States, which together account for some 45 percent of the globe’s total carbon dioxide emissions, pledged to make significant efforts in the next 10 to 15 years to limit their CO₂ emissions.

It’s the first time China has publicly committed to halting the decades-long rise of its CO₂ emissions. However, due to economic factors and policy shifts, China may be poised to achieve this goal even earlier than promised.

The U.S. pledged that by 2025 the amount of CO₂ it emits annually would drop to 26 to 28 percent below its emission levels from 2005. China meanwhile promised that its annual CO₂ emissions, which have increased by 257 percent since 1990, would stop rising by 2030 or earlier. China also pledged that 20 percent of its energy would come from sources other than fossil-fuels by 2030. That’s up from around 8 percent in 2010.

As recently as 2010, when China’s economy was still growing at more than 10 percent a year, it was unclear when its emissions might peak, says Valerie Karplus, a professor of global economics at MIT’s Sloan School of Management, and director of the Tsinghua-MIT China Energy and Climate Project.

But economic growth has slowed (it was 7.7 percent in 2012), and in turn so has growth in demand for energy.

Also, this year China’s government has already announced a plan to reduce air pollution by taxing and limiting coal use. Beyond that, carbon trading systems are now being tested in five cities and two provinces, and a national system is expected to come online in 2016.

In a recent modeling study that accounted for these new policies and assumed that China would accomplish ambitious near-term goals for expanding nuclear power and renewables, Karplus and collaborators at Tsinghua University in Beijing found that demand for coal could peak sometime between 2020 and 2025, and carbon emissions could level off sometime between 2025 and 2030.

But, says Karplus, there is still uncertainty over when China will begin actually reduce its emissions, and by how much. “It makes a big difference whether it peaks at 10 billion, 11 billion, or 15 billion metric tons of CO₂,” and whether or not the trajectory decreases rapidly after that peak, says Karplus.

Read the full article at MIT Technology Review